L76 Exhaust Manifold Numbers

[Clark K.]

One of the judges for the Mechanical Section at the Lone Star Regional gave my car's exhaust manifolds some originality deductions. The judge told me that it appears that someone (not me-prior owner) "ground down" all the protrusions on the manifolds. Therefore, they look show quality but NOT Top Flight quality. The number on the driver's side appears to be #3846563, but I am not sure. I cannot make out the passenger side #s since the A/C system is in the way.

So, I am in the market for another set of exhaust manifolds for a 1965 L76 engine with 4 speed and factory A/C. The problem is that the '65 JG does not show what the part numbers are for these. For my particular combination, that area is blank. Or, am I reading the table wrong? Any help with part numbers would be helpful. -Clark

[Joe C.]

Re: L76 Exhaust Manifold Numbers

Clark,

The photo shows the alternator on the left side, so you have air conditioning.
Exhaust manifold numbers as follows:

Left: 3846563
Right:3797942

You should also lose the cast blast on the steering gearbox, and the incorrect valve cover engine ID badges.

[Joe L.]

Re: L76 Exhaust Manifold Numbers

Clark,

The photo shows the alternator on the left side, so you have air conditioning.
Exhaust manifold numbers as follows:

Left: 3846563
Right:3797942

You should also lose the cast blast on the steering gearbox, and the incorrect valve cover engine ID badges.

Joe and Clark-----


Good luck finding an original 3797942!

[Tom P.]

Re: L76 Exhaust Manifold Numbers

OH MY!!!!
Yes, you're right, someone/sometime in the past those manifolds were ground down smooth. Looks good, but as you say, it's not NCRS "correct".

The 942 manifold (which is plain on each end) was never available as a service part---------thus, quite rare because it was ONLY installed on production cars. It was used on BOTH Vettes and Pass cars, 62-65.
It was used on many 300-375hp/327 Vette engines, but ONLY on some 300hp/327 engines in pass cars. So, either way, as Joe mentioned, it will be difficult to find one.

[Wayne M.]

Re: L76 Exhaust Manifold Numbers

Clark --- just so you know what to search for. Originals (unrestored) on my '65 L76/C60. You're right; it's difficult to get a pic on the passenger side because of all the A/C equipment. "563" thumbnail is on the left and "942" on the right.

The exh. mainifold table is on pg 111 of '65 TIM&JG.

Ignore obviously wrong misc. parts and missing items .

[Jack H.]

Re: L76 Exhaust Manifold Numbers

As others have mentioned, finding this version of correct/original exhaust manifolds is going to be a CHORE. And, when/if you DO find them, expect to pay $$$$.

If I were you, I'd consider simply living with the 'over restoration' deduction on the exhaust manifolds and spend your time/$$$ in other areas. It's hard to imagine that this SINGLE issue would prevent your car from earning top award honors IF that's the only thing awry...

[Clark K.]

Re: L76 Exhaust Manifold Numbers

It's hard to imagine that this SINGLE issue would prevent your car from earning top award honors IF that's the only thing awry...

Oh, no, I never wrote that this is keeping my car from Top Flighting. My manifold issue is just one of many issues I need to address. Are these manifolds not available as NCRS acceptable reproductions? Since this car is very rare, I have been encouraged to PV and ultimately Duntov this car. So, I know that I have a very expensive chore on my hands. -Clark

[Clark K.]

Re: L76 Exhaust Manifold Numbers

You should also lose the cast blast on the steering gearbox, and the incorrect valve cover engine ID badges.

Yes, I took originality deductions on the finish of my steering box, but that is easy to correct compared to finding some original, pristine exhaust manifolds.

But, Joe, what is wrong with the decal on the valve cover? I do not remember taking any deductions for this decal. As far as I can determine, the decal in question meets the requirements on Page 88 of the 1965 JG. My car has the L76 (365hp) engine.

[Joe L.]

Re: L76 Exhaust Manifold Numbers

Oh, no, I never wrote that this is keeping my car from Top Flighting. My manifold issue is just one of many issues I need to address. Are these manifolds not available as NCRS acceptable reproductions? Since this car is very rare, I have been encouraged to PV and ultimately Duntov this car. So, I know that I have a very expensive chore on my hands. -Clark

Clark-----


I think a reproduction of this manifold is available. It might not be 100% correct in every nuance of detail, but it will be NEW.

[William C.]

Re: L76 Exhaust Manifold Numbers

The original decals were water release, and were somewhat transparent at the edges. Yours look to be mylay with a full adhesive backing, easily seen as differing from an original.

[Wayne M.]

Re: L76 Exhaust Manifold Numbers

The original decals were water release, and were somewhat transparent at the edges. Yours look to be mylay with a full adhesive backing, easily seen as differing from an original.

Bill --- how would these judge ? From ML Dobbins, back in the early '80's. Water soluble.

Also, I would expect to see the decal installed just a tad higher (toward the fin). Refer to multiple pics in Noland's Vol 2 or contemporary magazine road test pics.

[Joe C.]

Re: L76 Exhaust Manifold Numbers

Yes, I took originality deductions on the finish of my steering box, but that is easy to correct compared to finding some original, pristine exhaust manifolds.

But, Joe, what is wrong with the decal on the valve cover? I do not remember taking any deductions for this decal. As far as I can determine, the decal in question meets the requirements on Page 88 of the 1965 JG. My car has the L76 (365hp) engine.

Clark,

You're learning that the "Book" doesn't contain every detail and nuance of originality which fully describes your Corvette and all of its components. John Hinckely put it best when he said that such a manual would require a handle! The only way to learn, fully, is to "get with" some people in your Chapter who know, attend National and Regional meets, attend Seminars, etc.

IIWY, I'd buy the reproduction exhaust manifolds as well as the proper water release decals, which are widely available.

[William C.]

Re: L76 Exhaust Manifold Numbers

Look like you and I bought at about the same time, the real deal.