The Stovebolt Site Forums The Shop Area Engine Shop Gutless in seattle

Hello, I have a 66 C20 with the 250 and monojet from a 68. It's fairly gutless in my opinion unless i keep the RPM's above 2 grand. Since I can't afford the Clifford set up,I wonder if Chevy ever made a 2 barrel manifold? Is it compatible with mine, and what models and years did it come on? What sort of gain might I get from such a swap? Thanks, Josh

There may be a 2bbl adapter you could use on your current manifold. Check this out:

http://www.stoveboltengineco.com/acartpro/product.asp?productid=91

Jim

Gutless turning slow is not a sign you need more carburator.

What do you mean be gutless? What are you trying to do? Are you towing big loads, going fast, or trying to accelerate fast?

Gutless going slow means you don't have enough low end torque for your desired result. No two barrel swap is going to fix that unless it also fixes something that is broken in your current setup.

I wonder if Chevy ever made a 2 barrel manifold?

Actually GM did but it was cast for (or in) Mexico or Argentina and not used and seldom if ever seen in the US. It was for the 230-250 engines.

I guess I shoulda bought that one I saw a few weeks back....The plate on the inside of the cab says 125hp @ 3800 RPM, I think. That just seems like not enough to pull anything heavy like a car or a bed full of dirt very well and be able to drive on the freeway at more than 60. It does have the 4.57 gears in the back and the four speed with granny low, so I don't expect it to ever really do more than 65 or 70. I'd just like it to be able to get there BEFORE I reach my destination....I don't need a race truck or anything huge. I'd like to make the power band just a little wider and/or bring it down just a bit. First of all, I know this engine wasn't designed for the track, so I don't expect anything like that. Secondly, it seems that even for the current setup, the intake and exhaust are rather restrictive. I was was hoping there was some middle ground in performance gains, since I can't afford to go whole hog and swap to the four barrel setup and do the split exhaust and cam and all the other things I hear and read about. Is there any middle ground? What options do I have other that the aforementioned four barrel swap? Thanks for your info, fellas

best option is ditch the 250! it'll never go fast haulin a heavy load

what you need is better gearing cuz with 4.57's you'll rarely see 70 on the road no matter what engine is in it, and then it'll be downhill, and the higher rpm power band of the 250 needs the 4.57's to have any power at low speeds

Bill

I found out another reason POSSIBLE for the lack of power. It seems that I have the 230, not the 250. The plate in the cab says 125 hp at whatever rpm, which is what the 230 has. The externals are the same, as are the head casting numbers. And then there's the lack of power that the 250 would have, 25 hp or so. Is this worth trying to do anything to?

Don't know if GM made a 2bbl manifold, but Clifford did. My neighbout had a 60 with a 230 or 250 (not sure which) and a 2bbl. Went well, but it had a new rear, a mild street cam and tube headers.

The 230 always was a gutlass engine. The 250 runs much better. You might find a carb off a 292. It has a larger throat & will add a little power. What size tires are you running? 457 is geared pretty low.

245/85/16 tires. I think they are the stock size. I think I'll be lucky to see 60 on the freeway.

I have to say it again. Your performance needs are for low-end and mid-range torque. Carb swaps are not the first thing to look at to get there.

Breathing issues, intake and exhaust, can make a difference, but think in terms of what is limiting your performance. If it runs good going fast breathing is probably not the problem.

Do a full careful tuneup, including setting the timing. Make sure you are making the best of what you have. Investigate advancing and retarding the ignition timing to see if it helps.

If it is a 230 the ugly truth could be that it just won't move that 3/4-ton truck with the finese you want.

My big pickup has a 454. I'm convinced the only way to get the performance I really want is to replace it with a 572. My pocket book isn't cooperating. So I've tuned it carefully and keep dreaming...

There's no replacement for displacement......

I think Wrenchbender and Oldsub have got it mostly right. The 4.57 gears aren't going to help you get 70 mph regardless of motor. Unfortunately you probably have an Eaton rear axle (removeable pumpkin), which means the best gears you will be able to find for it are 4.11. I'm a little surprise you have a 230 in a C20. A decent bent thing will cost a few $$$. I'd look for a 292 that someone has replaced with a bent thing. The 292 will have the bottom end of a 350. My 63 C20 with a 292 has hauled a cab over camper many miles. With out the camper I've have hauled more than few trucks on a trailer. One with a full size utility bed, I was down to 35 mph on a long grade, but the 292 will do that all day long.
Larry

I agree with you guys about the breathing issue. I only offered it as a minor solution to the lack of power problem. I only need this to be a "capable" work truck, nothing outlandish. Unfortunately, since it's the small six, I believe I will have to ditch the ttranny and the motor to put in a 292, which is what wuld probably be best. I don't need it to go any faster than 65 or so, and I actually rather like the tall gearing for pulling heavy stuff. I have done a thorough tune up, including istallation of a Pertronix ignition system, and it seems to run great for what it is. What it is, however, is not quite enough I think. .....Soooo....if I find a 292, what else has to be changed? Will the accessories from my 230 fit on a 292 with maybe only some bracket changes? By the way, the in the last post, a "bent thing" is mentioned.....what the heck's a bent thing?

The 292 is an easy swap. Most everything off the 230-250 will fit. It is about 2 inches taller. T.G. is right. That 292 will pull all day long. I used to maintain a large fleet of them. I believe By bent thing he means V type engines.

Why not just replace it with a bent thing. Chevy 350s are cheap and plentiful and my guess is the swap will be pretty painless. Parts are cheap too and it should give you more than enough power.

A V8, 4 barrel, 4.57, and anything over about 45 mph means the secondaries come open and the mpg goes from about what the 292 will get to half. One of the few advantages six is that everybody wants a V8. Patience and luck could get a decent 292 for less than half the cost of a V8, because someone replaced it with a V8. The exception might be he 292, but with luck.
Wrenchbender, left out the motor mount tower on the passenger side. The fuel is in the middle of the engine and the tower was moved back. I have one that is a little rusty you can have for the ride. Also the carb will be under size. The 230 carb has about 1 9/16 throttle bore and 292 is 1 3/4.
You haven't mentioned what tranny you have. I'm guessing it's sm420 with granny first. It will be fine with the 292. If you have the emergency brake lever on the floor next to the shift lever. The replacement tranny will have to have the emergency brake on it too. Or find an under dash lever, rear axle backing plates with emergency brake cables and everything in between.
Larry

Yes, but what else needs to go? I thought that the 230-250 had a tranny bolt pattern different than the 292-283-327. Thus I had the understanding that if I swap to either the 292 or a V-8, the transmission also has to go. Is this correct? Which brings me to whether or not the transmission length changes with the trans swap. What I want is torque, a pulling engine. Although, I can't afford a true stroker motor.It need not go fast, freeway speed is plenty, that being 60 or so. But I want it to be a good working engine. Would the 292 be better than a V-8? I'd also like to make as few mods as possible. WHile I'm looking into my options, what are your opinions on some variation of the GMC V-6? Thanks, Josh

How do I positively identify the transmission? I only know it's a 4 speed, and first gear only gets me to about 3 miles an hour. I think it's a Eaton rear end. The e brake is mounted up under the dash. I'm not ignorant to cars and trucks. I've just mostly dealt with Mopars, and so I'm really not familiar with Chevy's.

The transmission does not have to go. The 292 or v8 should bolt to your bell housing and nothing else changes.
This link should help you identify your trans

http://www.novak-adapt.com/knowledge/transmission_gateway.htm

Larry

If the transmission is original it is a SM420. I think a good running 292 might be a more satisfying choice than a 350 given what you say you want.

Bellhousing and transmission are the same for the 230, 250, 292 and the V-8's. A 235, 261 or GMC inline would be different.

Hea Steve, Slider here, What tranny ia C242? Any ideas? Where can i look it up. Thanks Pard/ Slider

Not that this is a solution, but if you're looking for a 2 bbl manifold for the 230-292 6, late 292 (late '70's-early '80's) had 2 bbl carbs. They used the rochester 2SE progresive 2 bbl. This is the same carb that was used on the early '80s Chevy ad Buick v6. It's bsically a primary and seconday from a Q-jet. Not a bad carb, though I find it a little finicy to work on.

Your tranny is a good solid truck tranny and as good as any for what you want to do(SM420 or SM465 most likely). You also have the gears you want for working. If hauling cars or dirt is what you want to do, I agree with most here that a 292 is the way to go. Your top speed won't change but the loads will feel much lighter. I'm not a mechanic but I believe it would be the easiest and most cost effective way to go as I'm pretty sure the 292 mounts to the chassis and the tranny same as your 250. For a little extra oomph, look for one that already has split manifold and upgraded intake/carb(s). Check out Ebay and inliners.org. Be patient. They are out there and they are cheap.
My neighbor has a 292 w/SM465 in an 80's 3/4 ton. It's a torque beast. I mooch using it sometimes for hauling and it's a fantantic work truck, highway or city.

I don't recognize C242. So I guess I don't know...