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Something NEW for the Bolters!

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HEI for your 216/235/261 Stock Distributor!

Kits are easy to install and do no harm to your vintage distributor.

The entire kit instructions are available at:


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#900418 - Sat Dec 01 2012 01:26 AM 235 UPGRADE TO DUAL EXHAUST AND DUAL CARBS ?
Roller Offline
New Guy
Registered: Mon Aug 20 2012 01:48 AM
Posts: 13
Loc: Palm Coast, Florida
I have a 1957 3100 series with a 235 6 cylinder, 4 speed transmission. I am thinking of installing a split manifold with dual exhaust and glasspack mufflers, also a dual 1 barrel carb set up. Looking to get better gas mileage a little better cruising speed on the highway and of course a real cool sound. Any input would be appreciated, pro's or con's, type of equipment good and not so good. Good idea - bad idea ? Enjoy your rides. Thanks_____Roller
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#900424 - Sat Dec 01 2012 02:15 AM Re: 235 UPGRADE TO DUAL EXHAUST AND DUAL CARBS ? [Re: Roller]
DrewP Online
Shop Shark
Registered: Tue Sep 26 2006 12:00 PM
Posts: 3745
Loc: Glassboro,NJ
Doubt you'll increase your gas mileage with dual carbs, but if you still want to do that, use an Offy dual single barrell intake manifold and a set of Fenton headers. Both are repopped if you can't find originals. You could use Rochester carbs, but Carters are better. Mufflers depend on how loud or mellow you want the noise. Cruising speed has a lot more to do with your gearing, not the engine.
_________________________
Drew
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#900428 - Sat Dec 01 2012 02:21 AM Re: 235 UPGRADE TO DUAL EXHAUST AND DUAL CARBS ? [Re: Roller]
RedGreen Offline
Shop Shark
Registered: Thu Dec 08 2005 12:00 PM
Posts: 297
Loc: Richmond Hill, GA
I have a '50 3100 with a '60 235 engine and 5-speed trans with dual exhaust Fenton headers and a single 2-barrel carb. I believe I bought the whole set up from Stovebolt Engine Co. Except for a minor whistle that I haven't tracked down yet, I couldn't be happier with the set up. I can't give any feedback on gas mileage as I haven't installed a working gas gauge or speedo cable.

If you're ever a couple exits north on I-95, let me know and I'll let you take a look/listen.
_________________________
1950 Chevrolet 3100 "One Step Forward, Two Steps Back"
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#900435 - Sat Dec 01 2012 02:51 AM Re: 235 UPGRADE TO DUAL EXHAUST AND DUAL CARBS ? [Re: Roller]
tclederman Offline
Registered: Tue Sep 18 2001 12:00 PM
Posts: 20831
Loc: Castleton-on-Hudson, NY

I have tried several configurations of different brand intake/exhaust manifolds, and I will soon be doing what RedGreen suggests. Dual exhausts and single two-barrel carburetor (using original intake).

RedGreen, what carburetor are you using?

If you want both parts "duals", check out dual Fentons for both, from this vendor. The Fentons match up with each other; but, the Offy intake and and Fenton headers require some grinding on all parts.

The intake needs to be heated. I think that the simplest and safest technique is to use a single line, exhaust heat heat-plate.
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#900441 - Sat Dec 01 2012 03:22 AM Re: 235 UPGRADE TO DUAL EXHAUST AND DUAL CARBS ? [Re: RedGreen]
Roller Offline
New Guy
Registered: Mon Aug 20 2012 01:48 AM
Posts: 13
Loc: Palm Coast, Florida
Thanks RedGreen. I would like to do that. Let me know when that is convenient for you. I am retired And basically available anytime.
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#900444 - Sat Dec 01 2012 03:35 AM Re: 235 UPGRADE TO DUAL EXHAUST AND DUAL CARBS ? [Re: Roller]
53moneypit Offline
Registered: Sat Dec 20 2003 12:00 PM
Posts: 2901
Loc: Smallville IN
Nothing wrong w/ the Fenton headers & Offy dual intake w/o grinding them but if does improve the fit. Basically it is the flat surface where they meet the head that is typically uneven so it will depend on your parts. I did not have to surface grind mine but getting a good fit was an exercise. Stay away from the Rochesters as has been stated. They are notorious for leaks. The Carter/Weber duals that Langdon sells are good carbs but are a little too much under full power for a 235. They are progressives so at little throttle they operate as two one barrel carbs and were original to 84 or so Ford Escorts. Electric choke so you'll need to do some wiring unless you replace the harness which is generally a decent idea on these old babes. Do not recam if you want a decent idle unless it's with a 261 cam (6 cyl. Vette cam).
Long tailpipes/no mufflers will sound better than glasspacs IMO. That is what we used to do back in the day or a single exhaust with a steelpac muffler.
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#900461 - Sat Dec 01 2012 05:15 AM Re: 235 UPGRADE TO DUAL EXHAUST AND DUAL CARBS ? [Re: Roller]
Mr. Lang Offline
Shop Shark
Registered: Sat Jun 21 2008 06:02 PM
Posts: 1506
Loc: Brentwood Bay, BC Canada
I ran this combo (offy+fenton) on my '50 1-Ton for 20,000 miles, several thousand with rochester B. and the rest with the carters.

I didn't notice any real seat of the pants power difference, when you consider that as you put your foot down, the throttle opens twice as fast. A 1-Ton that's always carrying a load is really a rocketship.

What I did notice though, was a SLIGHT improvement in fuel economy, about 2 mpg or so.

Where it really made a difference was at idle. I was able to get a much, smoother and slower idle. I really liked hearing that engine tick over.


It also looked really nice under the hood, and I liked that too!!!!!

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#900543 - Sat Dec 01 2012 02:14 PM Re: 235 UPGRADE TO DUAL EXHAUST AND DUAL CARBS ? [Re: Roller]
LONGBOX55 Online
Master Gabster
Registered: Mon May 08 2006 12:00 PM
Posts: 9102
Loc: DANVILLE IL
I'm in agreement with using Carter YFs, IF you can find a matched pair. There's a Ford variant that's not only jetted much richer, but is entirely different internally. Personally, I prefer the Holley 1904. Easier to rebuild, easier to tune, and jets are the same as later Holley 2 and 4 bbl carbs.
_________________________
Bill Burmeister
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#900629 - Sun Dec 02 2012 04:09 AM Re: 235 UPGRADE TO DUAL EXHAUST AND DUAL CARBS ? [Re: Roller]
RedGreen Offline
Shop Shark
Registered: Thu Dec 08 2005 12:00 PM
Posts: 297
Loc: Richmond Hill, GA
I need to check but believe I have a Carter Weber carb on my setup. Looking at the Stovebolt Engine Co website, he recommends these for dual setup only but mine has been running great for several years.

I didn't have any problems matching the Fenton headers with the original intake manifold, and don't have any heating system on the intake manifold. Again with the electric choke, I haven't noticed any issues. But I also live where the intake manifold can heat up just from the ambient air temp. No need for heat in my truck.

Roller, I'll send you a PM and we can meet up whenever you'd like. I am not retired but will always take a break from work to take the truck for a drive.
_________________________
1950 Chevrolet 3100 "One Step Forward, Two Steps Back"
Webshot Photos

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#900674 - Sun Dec 02 2012 08:16 AM Re: 235 UPGRADE TO DUAL EXHAUST AND DUAL CARBS ? [Re: Roller]
tclederman Offline
Registered: Tue Sep 18 2001 12:00 PM
Posts: 20831
Loc: Castleton-on-Hudson, NY
RedGreen,

If you have on single carb from Langdon on your engine, it is most likely a progressive 2-barrel Holley-Weber, not the much lower volume progressive 2-barrel Carter-Weber (made for use on a 1600cc engine),

The 235 is about 3800cc and the 261 is about 4300cc.
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