1957 round off road exhaust mufflers

[Joseph T.]

Can someone tell me the correct original GM part# and service # if any?

Thanks,

Joe

[Gary C.]

Re: 1957 round off road exhaust mufflers

Joe, the Mar 57 P&A book shows only 1 set of muffler part no.s; LH 3736957 & RH 3737644, both with exhaust pipe extension. Hope this helps. Gary....

[Joseph T.]

Re: 1957 round off road exhaust mufflers

Thanks Gary!

[Dave Suesz]

That was the same muffler

used on 55-56, the 3717324 (not available separately from the assembly with inlet pipes). There was also an optional Arvin muffler, externally the same, 3717324. In January 1957 this was replaced with a zinc-plated version, the 3744928. -From Ken Kayser "Countdown to Gold"

[Joseph T.]

Off Road Muffler

I wonder if there was a GM part # for the standard issue 1957 muffler and if there was a separate GM part # for the off road muffler...or were they one and the same?

Joe

[Art A.]

Re: Off Road Muffler

Joe, I can't answer your question specifically, but I can tell you this............ If GM parts were different designs they would have different part numbers. If GM parts were the same design and had different usages, they would/should/could have the same part number.

Art

[Joseph T.]

Re: Off Road Muffler

Art..thanks...Joe

[John H.]

Re: Off Road Muffler

Joe -

If I remember correctly, all 56's and 57's had the round straight-through mufflers (3736957 LH and 3737644 RH), and there was no "off-road" option; the oval-shaped mufflers didn't appear until 1958.

[Justin B.]

Re: Off Road Muffler

I agree with John, there wasn't an off-road option. It too is my understanding that all of the 57's had a round style muffler whether it be a low-horse or high-horse car. I personally fill the same about the 58's with the exception of all of them being changed from the previous year to the oval design whether it's a 230 horse or 290 F.I. If you look at all of the factory underbody pictures in the 1958-1960 section of Noland Adams book you will see that the high performance cars with the cross-over pipes still had oval mufflers, not round. My question is: why on the judging field would a 58-60 have points deducted for having oval mufflers if its a high horse car? Why would these cars be expected to be equipped with an option that no one can prove exsisted? I have the good-ole oval mufflers on my 58' big brake fuelie and I fill very confident that this is how all 58-60's should be. I think that this area of the judging section should be amended.