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Posted By: ClassicsR4Me Testing Daytona Universal Carburetor UN2 - Thu Jan 09 2020 08:59 PM
Greetings stovebolters. I recently looked up information on Stovebolt.com regarding the Daytona Universal Carbs, and it seems nobody had tried it out yet. I thought Id try it out and update everybody on this Carb.as I went along. So I decided to write to the company directly and ask them about their UN2 unit, and how it worked. The gentleman I was in contact with Mr. Ron Hewitt was very helpful and gave me allot of information regarding their carburetor. Ill put the detailed information he gave me later in this thread if anybody is interested. What stood out of what he wrote is that they've sold over 6000 units. Chevs of the 40's alone sells about 10-20 units per month. So I thought Id give their carb a try and inform everybody on my progress and results good or bad of this carb. Ill try to be as impartial as possible.
The test vehicle is my 1946 Chevy pickup. It has a 261 Chevy engine from I believe around 1958 (ill check on that later). Ive been running a Rochester Carburetor that was working great until a few months ago. The engine is nearly all stock. except for the 12v system with alternator. Its running regular points. When I first got it, It was giving me a consistent 12 M.P.G lately that's dropped to about 10 M.P.G I suppose mostly because for some reason ive been losing the fuel in the bowl (though I haven't confirmed this but will upon removal) and the need to crank the engine until fuel is delivered after it sits for a few days. I will set my points again, most likely at 18 thousandths. Ill also change the intake exhaust manifold to a nice painted one I have ready to go. Pictures of the installation coming soon. Heres what it looks like now.

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Posted By: ClassicsR4Me Re: Trying Daytona Universal Carburetor UN2 - Thu Jan 09 2020 09:10 PM
Was that his name? Coincidence I guess.
Posted By: MarkT Re: Trying Daytona Universal Carburetor UN2 - Thu Jan 09 2020 09:19 PM
Gabriel, your truck is a beauty. It looks great!. I would never remove my Carter but I'm interested in what you come up with.
Mark
Posted By: ClassicsR4Me Re: Trying Daytona Universal Carburetor UN2 - Thu Jan 09 2020 09:27 PM
Thanks Mark, yeah I love my truck, its a blast to drive. I was told that the best Carburetor to run on these engines is the Zenith Carb. Ive heard that they are very expensive though. These Daytonas are supposed to be copies of those, that's one of the main reason I was interested in trying it, besides the fact that its a brand new Carburetor. We'll see how it runs with it and keep it posted.
Posted By: Justhorsenround Re: Trying Daytona Universal Carburetor UN2 - Thu Jan 09 2020 09:36 PM
The Daytona has been poo pooed here since it first became available. It will be interesting to see actual documented experience with it. If folks will keep it civil and forget the snide insulting comments thus allowing you to be as unbiased as possible. Try not to go on the defensive and just report what you find. You will have to develop a thick skin as I’m sure some will not adhere to my above advise. Good luck.
Posted By: ClassicsR4Me Re: Trying Daytona Universal Carburetor UN2 - Thu Jan 09 2020 10:00 PM
Thanks for the heads up. I personally like to keep things original also, but as carbs get older and they are constantly rebuilt, they lose a bit of their drivability. I can always go back to the Rochester, but its nice to try something new and see how it works. Im curious to see how the Daytona performs. Might like it, or might hate it, never know till you try it.
Posted By: ClassicsR4Me Re: Trying Daytona Universal Carburetor UN2 - Fri Jan 10 2020 12:35 AM
It looks like my Rochester was losing fuel somehow. It looks a bit too low in the bowl. Can someone tell me where the fuel leakage usually comes from on the Rochester? Side by side comparison of the Rochester next to the Daytona. Customizations ill have to perform. The fuel cable bracket needs to be flipped over and upside down, then have the bracket bent down 90 degrees. Another thing ill need to change is the distributor vacuum line. On the Rochester its towards the front of the fuel air mixture needle, on the Daytona its towards the rear. I will connect it by rubber vacuum line. Also, wont be able to use my original heavy duty air filter. Regular air filter should be ok.

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Posted By: panic Re: Trying Daytona Universal Carburetor UN2 - Fri Jan 10 2020 12:38 AM
I don't think quality control is the problem, it's the idea that a few variants can be as close to the original mixture requirements as the many, many OEM carburetors. L6 engines of the same size will not require the same carb except by accident.
They may have developed the throttle disc size, venturi, jetting, vacuum setting, pump discharge, idle and transition hole sizes and locations, etc. on a specific engine, and will give good results... on that engine.
As your engine begins to differ from their model (displacement, CR, port size, cam timing, spark advance curve, valve area, overlap, rod ratio) the results will be worse - but perhaps tolerable.
Now, the 235 is an excellent model for this due to long use with very similar tune-up specs, so we certainly would like to hear results.
TIA
Posted By: SS396CV Re: Trying Daytona Universal Carburetor UN2 - Fri Jan 10 2020 12:47 AM
Looks like the Chinese Zenith knockoff I purchased. I used the carb on a test engine (GMC 248) and it performed well.
Posted By: ClassicsR4Me Re: Trying Daytona Universal Carburetor UN2 - Fri Jan 10 2020 04:00 AM
This is what Mr. Hewitt wrote in regards to that point. "The base Daytona UN2 carburetor has been in constant production in South America since 1957". I believe they are made in Argentina. They have a 1 year warranty for manufacture defects.
Posted By: truckernix Re: Trying Daytona Universal Carburetor UN2 - Fri Jan 10 2020 02:19 PM
I understand from the writeup that it has an adjustable main metering jet. That could make a big difference I think.
Posted By: carbking Re: Trying Daytona Universal Carburetor UN2 - Fri Jan 10 2020 02:20 PM
Originally Posted by panic
I don't think quality control is the problem, it's the idea that a few variants can be as close to the original mixture requirements as the many, many OEM carburetors. L6 engines of the same size will not require the same carb except by accident.
They may have developed the throttle disc size, venturi, jetting, vacuum setting, pump discharge, idle and transition hole sizes and locations, etc. on a specific engine, and will give good results... on that engine.
As your engine begins to differ from their model (displacement, CR, port size, cam timing, spark advance curve, valve area, overlap, rod ratio) the results will be worse - but perhaps tolerable.
Now, the 235 is an excellent model for this due to long use with very similar tune-up specs, so we certainly would like to hear results.
TIA



Totally agree.

Additionally, I have been unable to find any specifications of the items mentioned above by Panic. But my real issue is: where does one get parts????? One bad tank of fuel, the carb idle circuit is plugged, and the carb needs to come apart for cleaning.

If you need any verification of the parts issue, just find someone with a mid-1980's or 1990's I.H.C. tractor which was imported and renamed. We finally got enough requests to tool up rebuilding kits for some of them. This (I.H.C.) is a MAJOR brand, and information was available, just no parts.

I realize many today live in a throw-away world, but I don't!

Jon
Posted By: ClassicsR4Me Re: Trying Daytona Universal Carburetor UN2 - Fri Jan 10 2020 04:19 PM
They say they stock all components replacement parts, which is another plus. Heres what Mr. Hewitt wrote regarding adaptability : "Since the carburetor manufacturers could not continue to make each factory specific carburetor model, they would make a Universal to retro-fit original applications and unlike factory carburetors with fixed jetting and fixed throttle throw, the Universal models allow the full adjustment of the throttle lever to suit different hookup's; slotted base bolts to fit the small base US standard 1bbl (2 11/16") and also the larger flange (2 15/16"). The Universal carburetors also used a external adjustable high speed main jet to allow the fine tuning of the high speed circuit so you can match up the main jet orifice size to suit your particular engine, without tearing the carb apart and guessing at a correct jet size. This is a simple process based on the manifold vacuum your cylinders produce with the throttle open and the engine running at speed (2000-2500 rpm). Same principal as adjusting a idle circuit, except on the high speed side"
Posted By: Hotrod Lincoln Re: Trying Daytona Universal Carburetor UN2 - Fri Jan 10 2020 04:42 PM
Most carburetor manufacturers like Carter, Rochester, Stromberg, Zenith, etc. stopped using adjustable main jets back in the late 1930's or early 40's. Think of all the research and development money they could have saved by simply continuing to use technology that existed back when engines had 6:1 compression ratios, Babbit bearings on the crankshaft, and needed to be rebuilt every 30,000 miles! How does the power enrichment system get adjusted for such things as automatic or standard transmissions, different rear axle ratios, and other variables that aren't directly affected by either idle or main jet adjustments? The "one size fits none" approach has been tried repeatedly, and failed every time. Maybe this time it will be different. I suppose some people will be willing to accept mediocre performance from a universal carburetor because they don't know any better. Growing up eating 30% fat content hamburger is OK as long as somebody never gets served a prime quality steak, also.

I wonder if the average purchaser of one of these carburetors will have a 4-gas exhaust analyzer and a chassis dynamometer to help get those adjustments done correctly?
Jerry

Posted By: carbking Re: Trying Daytona Universal Carburetor UN2 - Fri Jan 10 2020 04:57 PM
Gabriel - that is an interesting answer, that really doesn't tell us much, other than you can order parts from Daytona at this time; how about elsewhere.

I have no issue with adjustable main jets, and consider them a bonus; however, they are NOT the major criteria in selecting a replacement carburetor. Internal size IS the major criteria, which is one of the issues to which Panic was referring in his post. One really great application of the adjustable main metering jet is the ability to temporarily retune an engine on a trip. As an example, if I were to leave Missouri (elevation where I live approximately 800 feet) and make a trip to Denver (elevation about 5500 feet).

When a customer asks us for a replacement carburetor; we have a list of questions.

(1) flange size (Daytona covers this)
(2) engine displacement and engine modification. These are critical in selecting the proper carburetor, as they give us information to determine internal venturi size, which is what determines the airflow characteristics of the carburetor. If it is determined that a specific engine requires a 24 mm venturi, and one installs a carburetor with a 27 mm venturi; one can adjust the adjustable main jet from all the way in to taking it out and putting in one's pocket, and the engine will always be sluggish at lower RPM. Conversely, if the engine requires a 27 mm venturi, and a carburetor is selected with a 24 mm venturi, then the engine is going to be sluggish at higher RPM, and in effect, the venturi will be a rev limiter.
(3) once the proper venturi is selected, then the adjustable main metering jet is useful to "tweak" the mixture for the volumetric efficiency of the given engine; but it will NOT compensate for using the wrong size venturi. Generally speaking, our customers never need to adjust the adjustable jet (if the carb we sell has one) more than plus/minus 1/4 turn (generally less) from the standard setting. And other tuning components are useful as well. As an example, Carter offers at least 5 different vacuum springs to help tweak the mixture for different engine vacuum profiles. This is not possible with a carburetor with an adjustable main jet UNLESS the adjustment is connected to a dial on the dash and may be adjusted "on the fly" by the driver.
(4) next question is cost versus performance. Not everyone wants to pay for good performance and reliability (one reason the Rochester B's are still somewhat popular). The Daytona carburetor certainly fits the "less expensive" criteria.
(5) we also ask about the terrain traveled by the customer, as there are some less expensive carburetors that may be used successfully if one drives in an area that is virtually flat.

But the key for you is that if you are totally happy with your purchase 5 years from now, then that becomes the ultimate criteria.

Jon.
Posted By: ClassicsR4Me Re: Trying Daytona Universal Carburetor UN2 - Fri Jan 10 2020 05:15 PM
You know allot more about carbs than I do Jon. I appreciate the information. I just thought id try it out and see how it worked. Im sure it wont be the best, but if it gives me decent performance then ill be happy. If it doesn't, then ill go back to my Rochester carb. Its just that nobody has tried it out and seen what it can do, so I thought id do that. Ill be working on it some more today, hopefully I can get it hooked up soon. It will take me a while of driving to see its response and fuel consumption. Another reason im trying it is my Rochester was starting to give me problems. It was leaking down fuel. I saw the intake manifold was wet with fuel and the carb bowl was low. So I would have to have addressed that sooner or later. Do you know what usually causes that problem?
Posted By: carbking Re: Trying Daytona Universal Carburetor UN2 - Fri Jan 10 2020 05:51 PM
Gabriel - much as I enjoy throwing rocks at the Rochester B's ( wink ); the carburetor probably is not the issue here. Rather it is the volatility of modern fuel. The Rochester B can leak down, but only if you park the truck on its roof (upside down wink ) Leaking down is a function of Holley carburetors, with the diaphragm type power valves, and a gravity passage direct to the intake.

Jon.
Posted By: carbking Re: Trying Daytona Universal Carburetor UN2 - Fri Jan 10 2020 06:43 PM
Gabriel - see my new thread.

Jon.
Posted By: Spotbiltxo Re: Trying Daytona Universal Carburetor UN2 - Sat Jan 11 2020 03:22 PM
Gabriel, I’ve enjoyed reading this thread. I appreciate you biting the bullet and buying this new Daytona carb so we can all learn from your experience. I’m really looking forward to reading about how it performs. Please post frequently.
Posted By: ClassicsR4Me Re: Trying Daytona Universal Carburetor UN2 - Sat Jan 11 2020 09:39 PM
Thanks Chuck, I appreciate it.
Here's the latest update. I installed the Carburetor with a temporary setup. I tried to put the old school glass bowl filter as I had it before, but was not able to find the correct fittings so I went without it for the moment. I installed the fuel filter that comes with the carb right after the fuel pump. Prior to connecting the fuel line I ran the fuel pump for about ten seconds until I could see clean fuel coming out as the instructions say. This seems to be an important step as the main reason for initial failure is that the carb gets debris inside and floods the carb. The engine started right up, idles perfectly, (as my Rochester did). Only downside I see so far is that I wont be able to use my original heavy duty air cleaner, as the mount is quite a bit smaller. The regular auto air cleaner (non heavy duty) fits right on there. I just happen to have an extra and will run that one in the meantime. Response feels nice and crisp when I touch the pedal. Now to wait for some sunny weather so I can feel if it has the same power, and see how it is on fuel consumption. I don't think ill have to worry about leaking the fuel out of the carb while it sits like my Rochester was doing.

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Posted By: ClassicsR4Me Re: Testing Daytona Universal Carburetor UN2 - Sat Jan 11 2020 09:43 PM
Here's a picture of my sparkplugs I was running with my Rochester. If I remember well, this light gray coloring means it was running well. Perhaps I should take them all out and clean them to see how the new carb is running. What do you guys say? On another note, I got rid of the pesky exhaust leak I had with new exhaust/intake manifold gasket and new exhaust pipe connection gasket.

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Posted By: ClassicsR4Me Re: Testing Daytona Universal Carburetor UN2 - Sat Jan 11 2020 09:48 PM
Time to adjust the High Speed Main Jet. I hope its as easy as it says in the instructions. Ill get back on that. Here also is a picture of the parts you can order in case you need to rebuild your carb in the future. To those who know Zenith carbs, is this a close resemblance to those carbs?

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Posted By: Hotrod Lincoln Re: Testing Daytona Universal Carburetor UN2 - Sat Jan 11 2020 09:55 PM
Reading spark plugs is a futile effort since they quit putting lead in gasoline. The white / tan/chocolate brown /black colors we used to look for don't happen any more- - - -plugs go from almost white for any normal fuel mixture to black and sooty when the mixture gets overly rich. Black and greasy still indicates oil burning. You're about 40 years late with that tuning method, which is why I mentioned a 4-gas analyzer, preferably one that can be rigged to monitor mixture during a road test. I ran a test like that on a 600-mile round trip to an advanced tuneup seminar sponsored by Snap-On about 20 years ago, but the doofus assistant principal at the school where I was teaching auto mechanics decided to clean out some file cabinets over spring break one year, and discarded the files, along with documentation of hundreds of chassis dyno and engine dyno runs. He was not welcome in my shop for a long time after that!
Jerry
Posted By: ClassicsR4Me Re: Testing Daytona Universal Carburetor UN2 - Sat Jan 11 2020 10:38 PM
hahah, I guess I am late on that tuning method. I hadn't read that information you mentioned anywhere. So much for that idea. Ill have to read up on 4-gas analyzers too. Thanks for the update.
Posted By: ClassicsR4Me Re: Testing Daytona Universal Carburetor UN2 - Sat Jan 11 2020 11:48 PM
Adjusting high speed main jet: Before adjusting air/fuel mixture as per instructions, I connected my timing light for the tachometer. Revved engine and set at 2000 rpm stayed pretty steady. On the front of carb, I turned the high speed main jet adjuster in (right) and the rpms started dropping to about 1980 rpms, I started backing up, turning out slowly, rpms started raising slowly 2020 was jumping between 2010, 2020, 2030. Kept backing up and rpms kept rising jumping about a bit 2050, 2060 until I reached a maximum of about 2080 or 2090 rpms and didn't see any more changes so I left it there. Next I hooked up my vacuum gauge to adjust air/fuel mixture. Started at about 21 lbs. of vacuum I adjusted in and out and looks like it was set pretty good from factory, stayed at around 21 and idled just beautifully. I was at 600 rpms idle and backed it down to 500 rpms, and was purring like a kitten. I revved the engine and it sounded allot throatier than before the fast idle adjusting. Now to put the air cleaner on and fill the tank to see what kind of gas mileage I get. Performance will have to be by my judgment. I was very content with the Rochester's performance but am excited to see what kind of performance I get now. We'll have to see how the UN2 does.

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Posted By: ClassicsR4Me Re: Testing Daytona Universal Carburetor UN2 - Sat Jan 11 2020 11:51 PM
Here's a closeup of the modification I had to make to the throttle cable bracket. I took it off the carburetor (two bolts), flipped it over, put it in the vice and bent the end part (where the cable is tightened) 90 degrees downwards. It wasn't too difficult and was content with the outcome.

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Posted By: Hotrod Lincoln Re: Testing Daytona Universal Carburetor UN2 - Sat Jan 11 2020 11:51 PM
Fortunately, 100+ octane racing gas still has enough lead additives in it to do plug readings after a few hot laps. I used to go to the track with 4 or 5 sets of plugs, and we might use all of them while tinkering with mixture settings during practice. A quick trip through the glass bead blaster got them ready for the next week's racing. With a good hot spark ignition system, plugs seldom "wore out"- - - -they just got dirty enough to need a cleaning if the mixture was a little off.
Jerry
Posted By: 4100 Fire Truck Re: Testing Daytona Universal Carburetor UN2 - Sun Jan 12 2020 12:01 AM
Fortunately the carb on my 1950 216 with 2500 original miles on it starts, and runs like it's fuel injected so far. They have had electronic injection 4 barrel setups for years now for V8's, and I even saw someone offers a 2 barrel fuel injection now. They are missing a big market leaving out the old 1 barrel fuel injection conversion, which would be great with a few mods on many old vehicles.
Posted By: Hotrod Lincoln Re: Testing Daytona Universal Carburetor UN2 - Sun Jan 12 2020 12:02 AM
What type of power enrichment system does that carburetor have- - - - -mechanical metering rods, or a vacuum controlled power valve? You're going to need a way to monitor the air/fuel ratio at light throttle cruise, and also at around 10 inches of manifold vacuum or less- - - -simulating hill climbing and/or passing. A small change in the power mixture will make a huge difference in performance and engine life- - - -too rich severely compromises power, while going lean wipes out exhaust valves, spark plugs, and possibly pistons. By the time you "hear" a lean preignition/detonation noise, you're way beyond safe power mixture limits. I prefer to monitor those parameters on a chassis dyno run instead of doing a road test. Good luck!
Jerry
Posted By: ClassicsR4Me Re: Testing Daytona Universal Carburetor UN2 - Sun Jan 12 2020 12:58 AM
You got me there Jerry, I can only imagine its mechanical. Do single barrel carbs usually have vacuum controlled valves? I think you would have been the best one to test these carbs out. My carburetor knowledge is very limited. I can only adjust the carb like any other regular guy can with the vacuum gauge. But I cant imagine its too far off its ideal. One can tell by the smell and the feeling of the vehicle if its too lean or too rich.
Posted By: Hotrod Lincoln Re: Testing Daytona Universal Carburetor UN2 - Sun Jan 12 2020 01:08 AM
"Different strokes- - - - -etc." I'm a firm believer in the slogan Sun Electric Co. used to put on all its test equipment- - - - -"We Test- - -Not Guess"!
Jerry
Posted By: ClassicsR4Me Re: Testing Daytona Universal Carburetor UN2 - Sun Jan 12 2020 01:16 AM
That's a slogan I can get behind. Unfortunately, until a professional tests one of these carbs out, my guess will have to do.
Posted By: ESum Re: Testing Daytona Universal Carburetor UN2 - Sun Jan 12 2020 03:55 PM
How about installing a O2 sensor in exhaust and using it to monitor mixture. Then tune accordingly.
Posted By: Hotrod Lincoln Re: Testing Daytona Universal Carburetor UN2 - Sun Jan 12 2020 04:19 PM
O2 sensor, vacuum gauge, tachometer, and an accurate record of fuel consumption on at least a 10 mile closed loop test course, and adjust the raw data from several test runs for temperature, atmospheric pressure, and humidity. Some of my really impressive dyno runs turned out to be a fluke of weather, not some magic we conjured up with fuel mixture and ignition timing. One of the best indicators of what's happening in the combustion chamber is an accurate record of exhaust port temperature. On the dyno, we had sets of exhaust manifolds and headers with thermal monitors for each exhaust port.
Jerry
Posted By: ClassicsR4Me Re: Testing Daytona Universal Carburetor UN2 - Sun Jan 12 2020 04:55 PM
That's a great idea, but probably a bit out of my price range. In any case, my idea is doing what a regular guy would do, getting the results a regular guy would get. The best I can offer is doing a city driving mpg's and a separate Highway mpgs. Though I imagine it wont vary all that much since I only run about 50 mph on the highway. I mentioned before, I was getting 12 mpgs (varied driving) averages with my Rochester, but later that dropped to 10-11 mpgs I attributed to losing fuel when parked for an extended period of time. As soon as the weather improves here in northern California, ill get to the testing.
Posted By: Hotrod Lincoln Re: Testing Daytona Universal Carburetor UN2 - Sun Jan 12 2020 05:16 PM
Be very careful about not getting that adjustable main jet too lean. Once the fuel/air mixture gets much below that ideal 14.7:1 (stoichiometric) mixture, combustion temperatures spike into the range where engine damage happens very quickly. One night we had a MOPAR 440 tractor pull engine on the dyno, making a final torque pull at 6500 RPM. Apparently, a bolt near the middle of the intake manifold had loosened up for some reason, and one cylinder went very lean due to a vacuum leak. I heard a very slight rattle from the engine, and before I could back off the dyno load and chop the throttle, that piston got a half dollar sized hole burned into it. Of course, the RPM/Torque calculations we made after the fact on that run yielded 714 HP running one 4 barrel carb and gasoline, prior to adjustment for temperature, pressure, and humidity. At those power levels, things happen very quickly.
Jerry
Posted By: Wally / Montana Re: Testing Daytona Universal Carburetor UN2 - Mon Jan 13 2020 03:01 AM
Sometimes trial and error is fun. Not for everyone, but it can be fun.

I think one reason the Stovebolt-6 has lasted so long is that it is forgiving. Forgiving for dummies like me.
Posted By: Hotrod Lincoln Re: Testing Daytona Universal Carburetor UN2 - Mon Jan 13 2020 03:41 PM
I've found over 40-sometning years of doing dyno runs that the "error" part of that process can get terribly expensive. Very few engines run well with an air-cooled crankcase (big hole in the block where a connecting rod used to be!)
Jerry
Posted By: carbking Re: Testing Daytona Universal Carburetor UN2 - Mon Jan 13 2020 03:56 PM
Originally Posted by Hotrod Lincoln
I've found over 40-sometning years of doing dyno runs that the "error" part of that process can get terribly expensive. Very few engines run well with an air-cooled crankcase (big hole in the block where a connecting rod used to be!)
Jerry


Jerry - on the other hand, if one installs a sleeve, then one can convert an inline "six" into a "seven" wink

Jon
Posted By: ClassicsR4Me Re: Testing Daytona Universal Carburetor UN2 - Wed Jan 15 2020 04:47 AM
1/15/2020 Update: The weather cleared up for a few hours and I was able to go fill up the tank. I think we might have near the most expensive gas in the nation (northern California). This was at Costco, which is usually about 20 cents cheaper than most places, $3.75 is the average for regular right now at most gasoline shops in town. My initial impressions, and I have to stress, initial impressions on a 30 mile round trip mostly highway driving are: In town, on the low end, about the same or perhaps a little bit more grunt than my Rochester. Smoother power delivery, and less jerking when I let off the gas abruptly. The UN2 helps my 261 idle beautifully at 500 rpms. Perhaps smoother that my Rochester did. I can hardly feel the engine vibrate. One thing I did notice with this carb was that when cranking the engine, I did have to tap the gas slightly to start out even when warm, something I never had to do with my Rochester. Now that might be down to the low rpm setting. I believe I was at 600 with my Rochester. High end driving: it definitely has a bit less grunt at the high end. Now this could be attributed to a few things. One, the air cleaner is noticeably smaller, with the larger heavy duty air cleaner I had on my Rochester, when I would gun it on an uphill in high gear, I would get a beautiful metallic vacuum sound that I loved, and you could hear allot more air going in, something im not noticing with this smaller air cleaner. (I have a paper air cleaner I might try to see if this will remedy the problem) Also, I adjusted the high speed jet without the air cleaner on, this might have something to do with the more sluggish power. I must note, that though it does feel less powerful on the top end, its not greatly noticeable, and there are some things I will try to remedy this. I will call the company and see what kind of customer service they give and what kind of technical advice is at hand. So far, im very content with the carb, with that small downside regarding the air cleaner. Ill definitely try to get some more miles on my truck and post anything I find that has merit announcing (weather permitting). Other than that, just see what its like living with the UN2 day to day, and what kind of gas mileage it gives me, first highway miles, then city driving miles.

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Posted By: Spotbiltxo Re: Testing Daytona Universal Carburetor UN2 - Wed Jan 15 2020 06:00 AM
Thanks for the update Gabriel. I hope you get good help from their customer service department.
Posted By: ClassicsR4Me Re: Testing Daytona Universal Carburetor UN2 - Wed Jan 15 2020 08:59 PM
1/15/2020 Update: Had a great experience talking to Ron over the phone at the Daytona Carburetors company. Sounds like a nice small outfit. Very knowledgeable gentleman. He took his time to listen to my technical questions and answered them clearly and calmly. It sounds like he's been working with carbs and in the automotive industry for a long time. What I learned. One is that originally GM ran the Zenith carburetors on these engines, (im not sure if he was referring to the 261's or stovebolt engines in general) and that these are a direct copy of those zeniths. These had the 32mm venturi on them, which was meant for these engines. I was happy to hear that and that they were OEM equipment on these Chevy's, that makes us purist a bit happier. I mentioned that I wasn't getting the high end performance I was getting before with my Rochester, he mentioned that perhaps my air cleaner wasn't allowing enough air to enter, or I simply hadn't richened the high speed jet enough and that I should first find out how many turns I had in fact turned out, by starting from the start (turning in and bottoming out the needle, its a very fine adjustment as I was told). I found out I was 6 3/4 turns out. I went 1/2 turn out more as instructed to see if that helps and to keep going out in half turn increments to see if I notice an improvement. He also suggested I test-run my truck without the air cleaner to see if that improves it. Another thing I learned is that the carb kit comes with a plastic red adapter to accommodate for larger air-cleaner base plate openings. He mentioned the diameter I believe it was 3 1/2 in. for the earlier type but they changed in 1960 I believe he said. I didn't quite understand how its supposed to work. Another thing I learned: I mentioned that I was looking for an adapter fitting (male to male) that would go from my glass bowl fuel filter to my UN2 carb. The one I had that worked on my Rochester was 1/8th to 1/8th mpt. but the inlet for the UN2 is a metric thread. So at no extra cost, (since I had ordered the carb from them) he said they would send me the 1/8th to metric fitting to my address so I can run my glass fuel filter again. Great customer service in my book. He wants me to follow up after I try the adjustments. Very content with my experience and am looking forward to dealing with them again in the future.
p.s he also suggested I run only 87 octane fuel because it has a higher boiling or percolating point which is 180-185 degrees Fahrenheit while 93 octane is approximately 40 degrees lower around 145 degrees Fahrenheit. Good to know.

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Posted By: carbking Re: Testing Daytona Universal Carburetor UN2 - Wed Jan 15 2020 11:13 PM
Classic - with all due respect, your last post is historically inaccurate.

Chevrolet DID use Zenith as original equipment..............................from 1912 to 1925 on a 4 cylinder 171 CID engine. These were updraft carburetors.

Chevrolet DID use Zenith as original equipment on their 6 cylinder of 299 CID......................in 1912 ONLY. This also was an updraft carburetor.

The last Chevrolet to use Zenith as O.E. was 1925.

Zenith did offer a replacement carburetor for the stovebolt 216.

Zenith did NOT offer a replacement carburetor for either the stovebolt 235 or 261

Zenith did offer a number of "universal replacement carburetors" of different venturii; and the customer was responsible for picking the correct one for his/her application.

GMC DID use Zenith as original equipment on many different size engines, and we have been recommending these GMC versions for years.

Jon.
Posted By: ClassicsR4Me Re: Testing Daytona Universal Carburetor UN2 - Wed Jan 15 2020 11:33 PM
Thanks for clearing that up Jon, I must have misunderstood Ron, as we spoke I was jotting down what he was saying. I have heard though that the Zenith carburetor is the better carb to have for our engines, and this is a pretty much direct copy. Do you know if perhaps they came as standard equipment for GMC trucks, because I did write that they came as standard equipment on GM products. That might be where the discrepancy lies.
Posted By: Hotrod Lincoln Re: Testing Daytona Universal Carburetor UN2 - Thu Jan 16 2020 03:57 PM
Back in the early 1950's, Dad used a big Zenith 2-barrel carb designed for a gasoline engine Mack truck on a flathead Ford dirt track engine. That carb had removable venturis, which he put in a lathe and bored out until the restriction was barely there, just enough to develop a little vacuum to pull the fuel from the float bowl. Then he drilled out the main jets to the point they would break off if they were tightened too much. Why all this modifying? He was running a mixture of alcohol and Hydrogen Peroxide as fuel, and the engine needed a LOT of it to run right. 8 laps per gallon on a 1/4 mile track was about average, running a 300 cubic inch engine. That single carb routinely outran competitors running three Stromberg 97 2 barrels. All the mixture tuning was done on a chassis dyno owned by one of his sponsors, one that was normally used for road tractors. Mixture adjustments were done by changing the high speed air bleeds, meaning that to get a richer mixture, a smaller air bleed was used.
Jerry
Posted By: ClassicsR4Me Re: Testing Daytona Universal Carburetor UN2 - Fri Jan 17 2020 11:21 PM
1/17/2020 Update: Took my truck out on another 30 mile round trip stint. Runs beautifully with the UN2 Carb. I tried the two things that were suggested to me, one, run the engine without the air cleaner to see if it was too restricted, two, I also backed of the fast idle screw a bit more. I was originally at 6 3/4 ill say 7 to keep it rounded. so I went back in whole turns to notice the difference I kept going to about 11 turns out and then notices a bit of fuel coming from the adjuster screw, I guess I went too far, so I backed it back in. I can say now with confidence that this carb has the same or just about near the same power as my Rochester in the top end. The idle is better for sure, and the low end torque feels as good or better. That coupled with the fact that its a new carb gives gives me confidence in my purchase. Now just to wait and see how it keeps up as time passes. Also, we'll see how much gas mileage it gives me, the same, less, or more. So far so good.
Posted By: Hotrod Lincoln Re: Testing Daytona Universal Carburetor UN2 - Sat Jan 18 2020 01:33 AM
There's too many mistakes and unscientific "tests" here to list. If you're happy with it, I guess the rest of us should quit commenting.
Jerry
Posted By: ClassicsR4Me Re: Testing Daytona Universal Carburetor UN2 - Sat Jan 18 2020 05:38 AM
Hi Jerry, Ive been honest since the beginning, im not a scientist or a professional mechanic. Just your weekend home mechanic that loves classic Chevys'. Nobody had tried this carburetor, so I thought I would check it out and document my experience, like anybody else would do at home. If you get something good out of it, then that's great. Im not recommending anybody buy this carb or not, just an unbiased test from a regular guy.
Posted By: Gord&Fran Re: Testing Daytona Universal Carburetor UN2 - Sat Jan 18 2020 06:12 AM
Interesting thread, thank you.

Looking forward to future updates.
Posted By: tom moore Re: Testing Daytona Universal Carburetor UN2 - Sat Jan 18 2020 07:41 AM
Yes, thanks for posting. Your experience and reporting will help others who are curious and want to read how it worked for a real purchaser and not some fabricated online review written by a company employee.
Posted By: ClassicsR4Me Re: Testing Daytona Universal Carburetor UN2 - Sat Jan 18 2020 03:47 PM
Thanks Tom. Thanks Gord.
Posted By: Justhorsenround Re: Testing Daytona Universal Carburetor UN2 - Sat Jan 18 2020 04:09 PM
Your every day man testing will be of benefit to the thousands of hobbyists that don’t have access to machine shops with dynos and hundreds of thousands of dollars in test equipment. Or, for that matter, the knowledge to use them. Keep good records and post frequently to keep interest up. The more miles you put on the more relevant your “test” will be. Don’t hesitate to post the bad (if any) along with the good. You’ve got a good start. Thanks
Posted By: moparguy Re: Testing Daytona Universal Carburetor UN2 - Sat Jan 18 2020 04:39 PM
Gabriel, another "Thanks" for taking the time to test and report. I bought a nos Zenith O-10355 (originally sold as a replacement for a 1937 ~ 1942 Chevrolet 216) from carbking to run on my 1951, 216 powered 3600. I have only praise for this carb. All that said, I recently added a 261 engine to the flock that will likely replace the 216 currently in the '51. It has the factory Rochester and I've been on the lookout for better carburetor. Your review could cause another Daytona carb to be installed when/if the 261 hits the road.

Added in edit: just been rereading earlier post and thought I'd add a test suggestion. As you're tuning for power it's easy to rely on the "seat of the pants" dyno. Most of us do. To add another test try this. Find a quite stretch of road, either make marks on the road or just identify a stop/start point with available landmarks that allow for precise identification within a foot or so. Then set your smart phone (or stop watch) to timer function. Drive at a steady (not accelerating at all) speed of say 40 mph and when you hit your first mark, put the accelerator to the floor and start the timer. Hold it there till you hit your second mark and stop the timer. Record the time and make notes on speed, wind, temp and humidity.

You now have a baseline to compare to when making adjustments that affect power. Although not likely to be worth the trouble with our truck and power levels you can find charts to adjust weather factors back to your baseline figures so you'er doing apple to apples comparisons.

Now make one change (only), go test and time, record all results, then repeat and report smile

If you really want to be thorough put the Rochester back on and do a test run, then one with the Daytona.

RonR
Posted By: ClassicsR4Me Re: Testing Daytona Universal Carburetor UN2 - Sat Jan 18 2020 05:09 PM
I'm glad to do it. The gentlemen on this site have helped me countless times when I've needed advice, with their years of experience. I'm happy to give back in this small way. That 261 is a great engine, I lucked out when I bough my 46 chevy, I thought I had a 235, but upon closer inspection found out I had a 261. I was very happy and am more than content with its performance. The Rochester B is an excellent carb, with its faults of course, but still gives stellar performance. When other stovebolters spoke of the Zeniths superiority, I wanted to look more into it. I've been told they fetch a handsome price, so of course when I learned of this near exact copy, and manufactured new, I knew I had to give it a try. I'm glad I did. It is brand new and working great, we'll see with time how it holds up. Ill try to keep everyone posted.
Posted By: ClassicsR4Me Re: Testing Daytona Universal Carburetor UN2 - Sat Feb 01 2020 05:28 AM
1/31/2020 Update: Just finished filling up my tank after putting 108 freeway miles on my pickup. It's been running great. I ended up putting 9 gallons of gas to the brim which averages out to 12 mpg's. This was driving at a pretty constant 50 mph with some average grade changes. I also did many full throttle pulls to test the high end power. I'm quite content with its power output. I still feel that perhaps the Rochester was a little almost unnoticeably better on the high end power, but the overall performance of the UN2 with its great idle, and low end performance more than make up for that. I also enjoy its performance right after cold startups, I don't have to warm up the engine as long to get smooth drive offs even when cold. Will update when I do a reasonable amount of city driving to average out its gas consumption.
Posted By: sstock Re: Testing Daytona Universal Carburetor UN2 - Sat Feb 01 2020 03:17 PM
Gabriel, if you are willing to weld in a 18mm bung in your exhaust down pipe, I will send you my hand held wide band to monitor air fuels.
Steve
Posted By: ClassicsR4Me Re: Testing Daytona Universal Carburetor UN2 - Sat Feb 01 2020 11:11 PM
Hi Steve, thanks for the offer. I would have no problem welding the adapter, but do you think it would make such a big difference in the outcome? It might be worth it even if I got one more mile per gallon, but from what I've heard, 12 Mpg's is pretty much the accepted fuel economy of these engines. Did it help you on your 261? What's your average mpgs?
Posted By: sstock Re: Testing Daytona Universal Carburetor UN2 - Sun Feb 02 2020 10:48 PM
I didn't bother welding in the bung because it runs so nice. I will do a mileage test when I bring it out in the spring and report back.
If you dont have drivability problems I wouldn't bother either. But if you have a problem you cant figure out, I have a wideband you can use in the future.
Posted By: 52Carl Re: Testing Daytona Universal Carburetor UN2 - Mon Feb 03 2020 01:36 AM
I would expect 15 MPG for a stock 216 or a 235 whether it has a ton in the bed or empty. I have verified this with each engine. The 216 has a Rochester model B, and the 235 has a Carter YF2100.
Posted By: ClassicsR4Me Re: Testing Daytona Universal Carburetor UN2 - Mon Feb 03 2020 06:36 PM
I have a recently rebuilt 235 with a Rochester B on it, im still averaging out its consumption. But my 261 seems to give me 12 mpgs no matter what.
Posted By: buoymaker Re: Testing Daytona Universal Carburetor UN2 - Tue Feb 04 2020 08:15 AM
Tidbits off the Internet for the Zenith 28 clone made in Argentina:

1.) 200 to 300 C.I. engines.
2.) 38 mm (1.5") throttle bore. Unlike Carter and Rochester, this carburetor has a removable venturi sleeve similar to the Zenith 28/228. I wish Daytona would share the sleeve diameter. This carburetor mounted on a 261 intake manifold will be 1.5" opening up to 1-11/16?". (My first thought, flow turbulence?)
3.) On a Jeep forum, a member contacted Daytonparts.com and a salesman made the statement that, "Our Daytona Universal replacement 1bbl carburetor will flow up to 195 cfm." Unfortunately it wasn't stated if that spec was @ 1.5" or 3.0" Hg. Note: At 1.5" Hg., a previous old posting here (May 55 Hot Rod) says 182 cfm was measured on the Rochester B made for the 261.
4.) There are options, that only a retail business can purchase, but these were not described.
5.) The manual says the adjustable main jet is preset for most engines for a correct fuel/air ratio. (My thought, yeah and bullfrogs have wings). For altitudes above 3500ft, follow the adjustment procedure (as described). Some owners have reported, at lower altitudes, they had to drive a distance, stop, re-tweak one revolution then repeat until it ran best. Last step was readjust idle speed to OEM spec.

Personally I would avoid buying any Chinese made carburetors (automobile, string weeder, chainsaw etc.) especially off of ebay. There is no quality control.
Buy from a USA company (even if they import) that will provide timely replacement parts and have good technical support. A business that will take it when stuff hits the fan.
Posted By: ClassicsR4Me Re: Testing Daytona Universal Carburetor UN2 - Thu Feb 06 2020 11:04 PM
Excellent, thanks for all the added information Buoymaker. Im sure it will be helpful to those interested in these carbs. As stated before, im still very happy with its performance. I would be hard pressed to tell the difference between the UN2 and the Rochester B. Its good to have another option, and if you want to go for a dual carb or triple carb setup and don't want to hassle with older carbs, this is a good way to go also.
Posted By: panic Re: Testing Daytona Universal Carburetor UN2 - Fri Feb 07 2020 01:25 PM
If the engine is large enough it will flow 300 CFM.
A displacement range between 200 and 300" cannot be bridged by just a venturi change.
Posted By: Hotrod Lincoln Re: Testing Daytona Universal Carburetor UN2 - Fri Feb 07 2020 02:55 PM
Panic, when someone has his mind made up, it's pointless to confuse him with facts.
jerry
Posted By: carbking Re: Testing Daytona Universal Carburetor UN2 - Fri Feb 07 2020 03:13 PM
Originally Posted by panic
If the engine is large enough it will flow 300 CFM.
A displacement range between 200 and 300" cannot be bridged by just a venturi change.


Of course it can; just ask the folks that sell them! wink

Is there a sarcasm emoji?

Jon.
Posted By: buoymaker Re: Testing Daytona Universal Carburetor UN2 - Fri Feb 14 2020 06:40 PM
The intent of my last post was mainly to provide information. I'm not "fer" or "agin" the UN2.
I'm just shaking the apple tree hoping to get a ripe apple to fall.

Wouldn't the Carter YF 4371S be a better "universal carburetor", to use on a 261, than the UN2?
Disregarding issues that may require modification to the throttle linkage, vacuum advance and choke etc.
Listed application for 230, 250 and 292 engines.
Throttle bore 1 11/16"
Main venturi 1 5/16"
Metering jet 0.104"
Metering rod (3 step) 0.078", 0.052", 0.045"

If yes, why not clone the Carter YF instead of the Zenith 28/228? Difficulty in manufacturing? Patent issues?
Posted By: ClassicsR4Me Re: Testing Daytona Universal Carburetor UN2 - Sun Feb 16 2020 06:42 PM
2/16/2020 Update: Received complimentary fitting from Daytona Carburetors. I was told by Ron, one of the technicians that these fittings are exclusive to them. It is a 3/8ths to metric. The Metric side goes into the Carburetor. It doesn't bottom out, its the flared kind, so just snugged down. Now the setup looks much better with the glass bowl filter. Now just enjoy driving it. Will soon update with city MPG's.

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Posted By: panic Re: Testing Daytona Universal Carburetor UN2 - Mon Feb 17 2020 02:23 AM
Obviously, I have no special insight as to which was chosen, but manufacturing cost always includes the number of precise machining operations (removable venturi adds expense), toxicity of components (cadmium is poisonous), number of individual parts (separate choke horn, throttle body?), etc.
Posted By: ClassicsR4Me Re: Testing Daytona Universal Carburetor UN2 - Tue Feb 18 2020 12:33 AM
2/17/2020 Update: Today I hooked up my small trailer to take some metal to recycle (around 200 lbs.), I have to admit, to be completely honest, under load I could notice the engine did have quite a bit less power than with my Rochester B. I wont say it was a remarkable amount but still noticeable. It was a small trip I took, perhaps a 3 mile round trip, but on the up hills I did notice having to go deeper into the pedal to power uphill, where I hadn't had to do with with my Rochester in the past. I'll continue testing the UN2 with an open mind. My Rochester can go on it later if I like and I do have a 235 engine I can try it out on to see if its a better fit for it. Still content with its better drivability in town, but will have to try a heavier load next time to see how it performs.

Attached picture Daytona 7.1.jpg
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Posted By: panic Re: Testing Daytona Universal Carburetor UN2 - Tue Feb 18 2020 01:20 AM
That may just have been a later cut-in point for the power valve?
Thanks for the research.
Posted By: ClassicsR4Me Re: Testing Daytona Universal Carburetor UN2 - Tue Feb 18 2020 04:04 AM
Hello Panic, I didn't seem to understand what you meant by cut-in point for the power valve? I think to the best of my knowledge, that I have the main jet set as far out as possible, I have really good vacuum, ill have to see if the vacuum advance is working correctly on my distributor. I know for a fact my fuel is leaking back down the fuel pump. That ethanol just eats away at the rubber parts, I can see the fuel go down in the clear fuel filter. I cant imagine how it makes its way back up to the gas tank, but it has to go somewhere.
Posted By: Hotrod Lincoln Re: Testing Daytona Universal Carburetor UN2 - Tue Feb 18 2020 04:30 AM
Your experimenting has pretty much proved what some of us suspected from the beginning. The carburetor in question does not supply sufficient air nor fuel to get the best performance from the engine, nor does it meter the fuel properly across the range of operation from idle to power production to light throttle cruise. The carburetor provides barely adequate performance- - - - -not optimum. It's better than a worn out, dirty carb, but not by much. Over time, it will probably deliver sub-part fuel economy as well. You might- - - -but probably won't be able to improve things by installing a bigger venturi and opening up the main metering system to flow more fuel than the wide open main jet can supply. Doing that properly will require more equipment and a more thorough understanding of carburetor theory and modification than you currently have at your disposal.
Jerry
Posted By: ClassicsR4Me Re: Testing Daytona Universal Carburetor UN2 - Tue Feb 18 2020 08:50 AM
Im glad you were able to arrive to a certain conclusion with my experimenting with this Carburetor, though I do not wholly agree with your assertion. My initial goal was not to surmise if the UN2's performance was equal to or greater than that of the Rochester, but if it helped you to come to that initial conclusion, then that is a good thing, though it is still a bit too early to conclude that as of yet. There are still other avenues I can explore before we have the final word. As I mentioned from the beginning, my purpose for trying this carburetor out was to gauge its quality, and craftsmanship, and also its utility with our stovebolt engines, not necessarily its performance. Seeing as how no one on stovebolt.com had tried this carburetor out, I believe this experience has been favorable, and shines a good light on this carburetor. Also, something to consider, one does not always chose a carburetor depending only on all out performance. If that were the case, we would all be running Fuel Injection, which gives the optimum air/fuel mixture for performance, driveability and fuel economy. For many reasons we continue to run Carburetors, be it Rochesters, Carters, Zeniths, Daytonas, etc. My sole experimenting as of yet has been on my 261 c.i engine, but there are still many other engines one could try this carburetor on, for example the 216 ci or the 235 ci, maybe even the 250 ci. and the 292 ci. Also,one always has the option of running a dual carburetor setup or even a triple carburetor setup, which I think this carburetor would lend itself well to, if performance is what your after. I believe that so far the UN2 has proven to be a good alternative if one wants good performance, great drivability, and quality of craftsmanship, but everyone can decide for themselves and come to their own conclusion on that.
Posted By: ClassicsR4Me Re: Testing Daytona Universal Carburetor UN2 - Tue Feb 18 2020 10:27 PM
2/18/2020 Update: I called the Dayton Company and talked with Ron, one of their older tech guys. Very patient, went through all the troubleshooting I can do to fix my low power problem. According to him, they test these carbs on their 320 ci Hercules engine. The UN2 is good for up to 275 ci with no problems. So it seems to be a problem on my end which I hope to remedy. One of the main things that I hand not changed was the timing. I don't know why it slipped my mind, but im sure that will be a major contributing factor. Ill do what conventional knowledge says and advance as far as I can before I hear pinging. Any other tips will be appreciated.
Posted By: panic Re: Testing Daytona Universal Carburetor UN2 - Wed Feb 19 2020 01:11 AM
I give up
Posted By: ClassicsR4Me Re: Testing Daytona Universal Carburetor UN2 - Wed Feb 19 2020 03:40 AM
I don't make them, that's what they told me. They're the professionals. It would be good to ask someone that has a 2 carb setup how it runs. How he tuned it and if he's content with it. I've seen it done many a time. Im not an expert, but ive seen Chevy 350's with 500 cfm 600 cfm 700 cfm up to 900 cfm carbs. It doesn't mean its specifically tailored to that specific engine, but im sure its close enough. I have a friend with a 366 Chevy engine (I had never heard of it either) with 2 progressively connected 600cfm carbs, he says he wants to go to a single carb 900+cfm Carb because though it does give him crazy performance, the in town usability suffers, that's a 300cfm difference but im sure its going to run great, I doubt anybody would criticize him on not having the exact perfect carb for his engine . 235 and a 261 engines are not precision modern machines (though in their time they were), im sure Rochesters and these UN2 units can be adjusted to give adequate smooth performance as ive seen done with mine (and im still tinkering with it). I cant come to grips with some peoples opinion that the carb has to be perfect to that engine. In that case, there would be no aftermarket carburetor dealers, Edelbrock, Holley, Demon, and who knows how many others.
Posted By: Doc.Hall Re: Testing Daytona Universal Carburetor UN2 - Thu Feb 20 2020 06:39 PM
I'm a little late coming into the conversation, this carb. (UN2), is produced primarily for the S. American market. A lot of old cars which the original Rochester "B" will work on are there. Cuba has them on everything! Like the song by Jackson Brown " you can see a Soviet transmission in a Chevrolet". I'm a Rochester model "B" fan(atic), the reason that ClassicsR4Me is having trouble with the gas drain is one of 3 reasons: leak in fuel bowl to air horn gaskt., fuel line leak at carb or the Throttle body shaft. These old carbs can only be rebuilt so many times and beginners have a tendency to warp the air horn. A whole big bunch of thanks to Classics R4Me, great job and very attentive to his testing and follow up.
Posted By: Doc.Hall Re: Testing Daytona Universal Carburetor UN2 - Thu Feb 20 2020 06:51 PM
moparguy, the 261 c.i.d. normally uses a a .065 metering jet rather than the most popular .058. Good luck. Doc.
Posted By: ClassicsR4Me Re: Testing Daytona Universal Carburetor UN2 - Fri Feb 21 2020 03:12 PM
Thank you for the information Doc. Its good to know these carbs are widely used and working in many applications. Your correct about my Rochester, it looks to have been rebuilt a few times and though it gave me very good service, I just wanted to try a new carb to see how it would perform. Im still fiddling with it, im sure I can get a little more performance from it yet.
Posted By: Wally / Montana Re: Testing Daytona Universal Carburetor UN2 - Fri Feb 21 2020 04:04 PM
I've been following this and have wondered "What would the original owner of my '48 do?" He'd probably slap on the UN2, if needed, and go feed the cows. Picture shows where my '48 grew up on the Rocky Mountain Front.

I love how forgiving our trucks are.

Attached picture RockyMountainFront Wide1000.jpg
Posted By: ClassicsR4Me Re: Testing Daytona Universal Carburetor UN2 - Fri Feb 21 2020 11:23 PM
Beautiful scenery and beautiful truck. Thanks for sharing.
Posted By: ClassicsR4Me Re: Testing Daytona Universal Carburetor UN2 - Wed Sep 30 2020 11:18 PM
Update 9-30-2020 : I finally got back to rebuilding my older “bigger” single barrel Rochester to put back on the 261 in my 1946 Chevy. Driving them back to back, I would say the Rochester has around 5-10% more horsepower at the top end. I put the Daytona Carburetor on my 235 Stovebolt in my 47 Fleetline and it is a perfect match. Same power output to me as the “regular” single barrel Rochester with the benefit of having a new Carburetor. As I mentioned before I’m very content with the Daytona performance. I’ll be doing a gas mileage test but I imagine it will be similar to the Rochester. I hope this info helps whoever is interested in these Carbs.

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Posted By: 52Carl Re: Testing Daytona Universal Carburetor UN2 - Thu Oct 01 2020 12:33 AM
A 235 would likely get 15 MPG if you dribbled gas down the carb out of a boot whether the bed was fully loaded down of empty.
Posted By: ClassicsR4Me Re: Testing Daytona Universal Carburetor UN2 - Thu Oct 01 2020 12:45 AM
Greetings Carl. The 235 is actually in the Fleetline, and I was getting 14mps with the Rochester, I hope the Daytona will do a bit better. My 261 got 12mpg's with either Carb. Both are running great.
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