Old Big Block Racer question

[Jerry G.]

My buddy is putting together a ZL-1( Modern block from GM) for his 68 Corvette road racer. He is wondering what intake manifold was use by the serious road racers for this block? Was there an " out the back door" intake manifold or was it the same as use on L 88? Help from you guys who were there would be greatly appreciated. Jerry

[Joe L.]

Re: Old Big Block Racer question

Jerry-----

The L-88 manifold was probably the most commonly used manifold of the period for road racers. If GM made any oter manifolds for the period, they were extremely rare and one likely couldn't locate one now, anyway. To my knowledge they didn't, though.

[Loren L.]

Try Dick Guldstrand at dick@guldstrand.com *NM*

[Joe L.]

Addendum

Jerry-----

By the way, the L-88 manifolds are as follows:

1967 and early 1968---3885069

This manifold casting was manufactured into several finished manifolds. The L-88 version had an open plenum and can be made from any of the other versions by grinding/machining. The PART NUMBER for the L-88 manifold (NOT found on the manifold, itself) was GM #3886092.

later 1968 and 1969---3933198

The GM PART NUMBER for the above-referenced manifold was GM #3947083

Manifold GM CASTING and PART NUMBER 3933163 is still available from GM. This manifold is identical to the GM #3933198 except for the full open plenum. The GM #3933163 can be modified to be functionally identical to the 3933198 by machining/grinding of the plenum.

[Bill Stephenson]

Re: Old Big Block Racer question

Jerry,

------You dont state weather the manifold has to be a factory peice. If not there are some really good intakes out there nowdays! Some with an air-gap underneath the plenum are especially good at keeping the incoming charge as cool as possible. Your friend needs to talk with those who know all the choices as manifolds need to be tailored to the intended RPM range..........Bill S

[Bryan L.]

Re: Old Big Block Racer question..where's Clem? *NM*

[Mike M.]

Re: Old Big Block Racer question..where's Clem?

i heard clem was outside punxitawney pjil's burrow, with an axe, anticipating fresh whistle pig stew. mike

[Chas Kingston]

[Clem Z.]

Re: Old Big Block Racer question..where's Clem?

we are alive and well in fla. if you used the open plenum intake you need a a special carb with modified boosters to get the proper fuel distribution. you also need to stagger jet the carb but the boosters are needed even with the staggered jet carb. you can compensate for the boosters by proper stagger jetting but i need to be at home to get the correct jetting. joe can supply the proper carb list # for the manifold,i think it was list 3496. i may even have one of these carbs but i will not be home till after march 4

[Craig S.]

Re: Old Big Block Racer question..where's Clem?

Also list 3418 is is an L88 stagger jetted 850 Holley that they sold up until a few years ago. I has the enrichment tabs on the boosters Clem mentions as well, and flows 850CFM. I had a new one circa 1989 for a crate LS6 going in my 74, but I ended up with a 67 tripower instead and sold it on eBay a couple years ago (probably a mistake, now they are gone and getting more costly)...Craig