A good dremel will take care of that tunnel... Spray Arid Extra dry on the hood, use globs of play dough on the air cleaner, one in the middle the rest around the edge when you lower the hood the play dough will leave marks. You will see its a little off center, I cut a cardboard circle a little bigger than the air cleaner and traced around it on the hood then cut it out. It actually works out good if you take the flapper off the hood the air cleaner is siting in the path of the cooler air coming in...

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I did not know about the change in frame thickness ! Do you know if there are published frame rigidity tests comparing before/after ?

I factored in changes to the rear end diff and other components. Also considered some info after researching torque tubes. The best answer is probably a good cage.

Definitely want to avoid cracked fiberglass !

Still interested in hearing from people who have accomplished this change.

 

To keep adding to this thread...not being a nay-sayer, just a mechanical engineer!

Springs will have to be up-rated all the way around.
Bilstein yellows are a must.
(I'm definitely not a coil-over kind of guy..theres' no suspension travel to begin with!)
Attend to Cooling,.. your radiator is a small block radiator.
One big PLUS about the 80-82 'shovel-nose' body is 50% more cooling air into the radiator!
I'm not a lover of the 12 point half shaft yokes....again down-rated.

Obviously this can be done...just be aware of the pit falls.

As far as I've been able to research, I have never actually seen torsion and beaming rigidity tests, computer or otherwise on the lightened frame. Assume 20% less or more, than a 79.

Good luck and SUBSCRIBED!

Unkahal

 

I'd recommend the ZZ502 from GM Performance Parts. It comes with aluminum heads. With an aluminum intake, aluminum water pump, the engine weight is, I believe, in the range of the iron small blocks in the C3's. 502 hp. This could stress the Dana, but the rest of the drive train should survive if you don't aggressively drag race. The L88 optioned C3's were sold with the same drive train as the other C3's and these engines were rated at 550 hp flywheel hp. They were well suited for road racing with the standard drivetrain. As for hood clearance, a standard BB/LT1 hood should work. You will need a custom "long" hood. L88 "long" hoods are readily available and this will alleviate the hood clearance problem. You probably can use the L88 cold air function as a bonus. The 502's have the block deck height as the traditional BB's, so valve cover clearance with the PB vacuum canister shouldn't be a problem.
........................................
I've never read that the factory L88 cars had anything much different in the drivetrain than the other C3's. A "long" C3 hood is for C3's that didn't have the early C3 windshield wiper doors. Also, BB's in C3's really need, IMO, aluminum heads. The 650 pound weights of the all iron BB's is just too much weight for a C3. The aluminum heads weigh 42 pounds each. Mine do. This means the iron heads must be north of 100 pounds each. Gross.

 

The Edelbrock Torker II is supposed to fit under a stock Big Block hood. As far as how good it is you need to do your research on it. some people don't like them and others have had good success with them. Either way they are probably at least better than a stock low rise BBC manifold.

 

The earlier 80-81 hoods did not have the big ram air plenum underneath...maybe 2" more inches.

Unk

 

Dear Dave,,,here's a 'giftie' for your project.

Best of luck Unkahal

https://lasvegas.craigslist.org/pts/...394056786.html

 

Wow that thing's big !

 

,
This allows you to cook a 22 lbs turkey on top of your aircleaner! Its a BB, so might as well USE all that underhood heat!

Unk

 

#2: I've heard about the reduced frame wall thickness many times, but I've never seen any actual official documentation regarding it. Can you link something regarding this item?

 

I got these dimensions from TOM FALCONER. NCRS 'czar' for all Europe. Based (formerly) in the UK...DBA Claremont Corvettes.
The dimensions are in EVERY one of his books.

These dimensions have been VERIFIED in this forum BY ACTUAL MEASUREMENT OF FRAME WEB THICKNESSES.

(It's a FACT, jack!)

Cheers Unkahal

 

Do you have any proof at all that the thinner frame will buckle under a big block ? One smidgen of proof ? Any documents that support your conclusion ?

 

you don't break things with a big pretty engine. you break things by abusing them. if you want a big block because you want one, ok. a gen 6 454 for 300 bucks will do for starters. if you want to try to get into the 12's or better, a sturdier drivetrain is a must. you can break stuff with a 165 hp 75 engine if you try...

 

i did not say it will buckle...nowhere, did i say that!

Frames twist. This is called torsional rigidity. When you remove 20% of the metal, torsional rigidity goes down....simple fact of life.

unk

 

I would go LS over a big block but either way you have to address the rear axle, But a big block would be cool. There is a guy on the other forum doing this swap on a 1981 and swapping to a manual. He is doing a 502 if I am not mistaken. Either way subscribed, I plan on going LS or Big Block eventually on mine after I get it going with my small block.