Hi everybody!

I have a -76 455 cutlass with J heads and only want to wake it up a little bit.
If I change the cam, intake manifold and put on a KN-filter what will it do to the engine in hp/torque?
I´ll keep the original carburator, exhaust manifold but make it with dual pipes.

And at last can somebody please tell what cam and intake I should use, i´ve tried to serch the fourm but I can´t find a set up.

Regards

Mattias from Sweden

 

The heads are the thing holding that motor back. I wouldn't do anything else until the heads are fixed.

 

I agree that the J heads are the "bottle neck" that will hold the engine back. The J heads combustion chamber is a little bit larger than the previous years heads plus they are restrictive. If the short block is in good condition, I would find a nice set of rebuilt G, Ga, C, K, Ka, E heads either small or large valved. A small RV (torque cam) Comp Cam has a couple. This way you can keep your factory bridges and rockers. Buy matched valve springs. Keep your factory intake, unless you want to put a Edelbrock Preformer. New timing set. The small increase in compression, less restrictive heads and the camshaft &springs with fresh timing set will make your engine think it's on steroids, ha ha but true. I have a similar setup but with headers (Comp Cam 0.456/0.456 lift) in my convertible and it's pretty frisky. JMO. That's about the cheapest best cost upgrade and still very drivable. Good luck.

 

i just did everything kennybill suggested to my 76 455 ,im still in the test and tune stage ,but i can tell you its a whole new animal .

 

Thanks for all answers.

It might be the way for me to do that or I just got an offer for a 455 jet boat so maybe I buy it and switch it.