VCCA Home Forums TECHNICAL - 1945 AND NEWER 1955-1957 '57 exhaust?

I would like to keep the duel exhaust that I put on my '57 years ago, but since then I have read that only 4 bbl carb. cars had the duels in '57.

I want to keep the car all original; car came with a 283 with a 2 bbl carb. If memory serves correctly I think this motor information is on the cowl tag and I want the car to match its' tag.

Is this memory correct?

What are the pros and cons concerning 2bbl vs. 4bbl?

Thanks

In 1957 the dual exhaust was part of the Power Pack set up.It consisted of 4 barrel carb.,dual exhaust and higer compression cylinder heads.This increased the horse power from 185 to 220.The front to rear brake and gas lines also ran on the outside of the right frame rail-single exhaust on the inside.This was done to keep the exhaust heat away from the lines. It will be easy to see if the car originally had single or dual exhausts by the placement of the lines.

4 Bbl. carb will give more power at full throttle and at higher RPMs.If driven sainly usually produce better gas milage.Today the 4 Bbl. air cleaners sell for $200 +.....carb. and intake another $200 -and then the carb. may need rebuilding.Also requires some different linkage.

For normal driving the 2 Bbl. is sufficent.

PS-I assume that you have an automatic transmission as the sticks with a 2 bbl. in 1957 had a 265 engine.

Gator: the 57 chevys with 250 and 283 hp engines also had dual exhaust.mike

It is an automatic.

The car was unrestored and complete when I got it many years ago. It had a single exhaust and I changed it to duels for the sound and looks but kept the 2 bbl carb.

I have an original 4 bbl intake on the shelve (w/dirt dauber filled in holes) in my shop, but I don't have an original 4 bbl air breather or carb.

I would like to have duels but don't want to use them if 2 bbl cars ONLY came with a single exhaust.

Chevgene, I didn't know the lines were different, but it makes sense, I put the lines back where they were so they would be inside the frame rails because it was a single exhaust in the beginning.

Do you guys think the lines (inside the rails) for a single and duel exhaust would be a problem?

Mike, are you saying that 2 bbl (non-power pack) 57s had duel exhaust installed at the factory?

This is like dominoes, change 1 thing and then you have to change something else, and then something else, etc, etc... on and on and on...

Might be smart to just put the single exhaust on and live with it...

The 250 and 283 hp engines were fuel injected. the 250 hp had hyd lifters, the 283 had solids as well as other differences. mike

Yes, a 2 barrel car never had dual exhaust in 1957.Was only available (and standard equipment) on 4 barrel,dual 4 barrel and fuel injected cars.

Would the fuel and brake lines inside the frame rail cause a problem?...I know of many that had them in this manor and caused no problem.BUT-with todays gas,with its lower boiling point, it could cause problems with vapor lock in hot weather.Also if you want a "correct" car it would need a 2 barrel carb.,single exhaust and lines inside the frame.Moving the lines outside isn't the worst thing to do.The pre-bent lines with the stone protectors like the originals are available as is the other hardware needed.

When I was working in the local Chevrolet garage in 1956 I put duals on my 56 210 tudor.They came out of a GM box complete with outside brake lines and even a plug for the crossover pipe. I dont know if they sold these in 57 because my 57 210 hardtop [yes the kinda rare one] came with power pac and stick shift.I remember that they installed several set on new cars .Would ChevyGene know if they made them for 57 ?

The dual exhaust change over kit was made only in 1955 and 1956 (both different).Kit came with new brake lines as well as exhaust parts (and exhaust extensions).

Not available in 1957.

Thanks Gene I was not sure about 1957.

Cool information, I think I will take Chevgene advise and go with the single exhaust.

I really don't want to get into changing parts (intake, air cleaner, lines) now that the car is almost finished.

A follow up question on exhaust:

What muffler should I put on the car?

Want it to be like original if available. A brand name or model name would help also.

Thanks again guys for the help.

find a muffler with a smooth outter shell.The outter metal covering had no ribs, diamonds or other designs stamped into it.GM had more than one muffler supplier back then.Walker and Arvin if I remember correctly-but- all were made to Chevrolets specifications.

What was the shape? Round, squashed egg shaped, or ?

About what size? Length and diameter.

Natural steel color, I assume.

Thanks!

The muffler shell will be about 34"
long.It is of the flat oval design.Most of the modern replacements are of that shape.

Shafer's Reproduction has the most accurate repro muffler.

The original muffler's end bells were convex. Today, they are all concave.

Thanks guys, that gives me enough information to get both the pipes and the muffler.

Would I lose points with aluminum or ss system?

Also, is there a big difference between a pipe system ordered from a catalog versus one made at my local muffler shop?

Judges, at least in NCRS, will carry magnets to detect non-original stainless exhaust systems, gas/brake lines etc. they are unable to detect aluminized systems(as the systems were "mitted" with a preservative at the factory(c-1 and c-2's) . I'd get the system from a catalog as they are usually bent based on computor driven machinery utilizing factory blueprints whereas the Bubba at the local muffler shop may or may not do a good job. mike

This all of this depends if you are building a points car. My '56 is a 265/PG w/2bbl and it has duals installed and retains the original inside fuel/brake lines. I can drive for an hour and grab ahold of my glasspacks and they are warm, but not too hot to hold on to for a few seconds. I have used a lazer thermometer and checked the heat on the down tubes and it was below 170°. I don't see any reason if you want them not to put them on.

As for those judges..... give me a brake.... some things just get way out of hand... Oh, my '56 is my daily driver too, I've put 25K miles on it since I got it in Aug. 2002.

IF you are wanting a PowerPak intake and carb set up for a manual tranny, I have one for sale also, in good running condiditon.

I have forgotten, what exactly is on the cowl tag about the accessories or motor set up? Can you tell if car came with a 2 bbl or 4 bbl?

cowl tag really doesn't say anything about the motor. It will show some codes for accessories. body style--paint code. The letters on the tab by the right cylinder head/block have the engine code. i.e FC--Post the numbers and letters and it will be deciphered.

Thanks, will get them ASAP.

clssy 56: " as for the judges, give me a brake"----If the judging philosophy is to restore to "as it left the factory"( as is the case with the National Corvette Restorers Society) then the judges have the responsibilty to determine if a given part is or isn't identical to the piece that left the assembly line.i realize that other antique auto clubs do not suscribe to ncrs philosophy. as you related to gator, it all depends on what one intends to do with the vehicle after the restoration.There are plenty of modified Corvettes that show up at NCRS meets but they usually aren't judged in the Flight Class, as NCRS has instituted classed that address non-original vehicles.Guess it all boils down to what winds your clock. regards, mike

There is a great temptation to add on accessories to our "toys", some are for safety reasons and a lot for "the look" or "the sound" that we like. It is hard not to want AC, PS, PB, duel exhaust, 4 bbl, etc in a car today, especially if it was an option when the car was built.

Now I can do without the tissue dispenser and the record player and the continental kit, but please don't take my fender skirts... or my seat belts...oh, and if I ever find some; the duel rear antennas…(maybe).

Sometimes it looks like the car is only there to hang all of the accessories on.

But like the man said, "it's your ride, do what pleases you, not others (except the wife)".