C1 Crate Motor Swap

[Terry D.]

As a winter project this year I am looking at a new GM crate motor, probably the 383ci version. This subject was touched on before in a previous post, but when asked to go into detail the subject was dropped. If someone has done this swap would you please post any problems if any I might run into. Thanks in advance.

Terry

[Jim T.]

Re: C1 Crate Motor Swap

Going to pull the 62's 327 and save it for increased value when time to sell? With the previous posts on rod failure the GM crate engine is a way to have some fun. The ZZ383/425 will have a little less HP with a dual plane intake purchase, about 15-20, according to GM's Performance Part Book. You will need the dual plane for hood clearance. You will not get a distributor with the engine, so you can use your 62's with a new distributor gear #10456413 used with steel roller cams. This engine comes with a flex plate you don't need and you will have to buy a flywheel. If you are going to use your original exhaust manifolds you may have to use gaskets between your manifolds and the aluminum heads for prevention of exhaust leaks. Reason I say this is that my original 70 exhaust manifolds leaked a little bit and after the engine was stated for the first time is when the leakage was known. I used the exhaust gaskets that are used on the C4 cars. Also mate up an exhaust manifold to the head and make sure it will mount without valve cover interferance before installing the 383. Make sure your new flywheel is the same size as your 62's so you can use your original starter if you want. One other thing, since this engine has a roller cam, you don't have to run it to break in the cam and lifters like what is used for non roller cams. I installed my ZZ crate engine about 12 years ago, still no oil leaks, and I do enjoy driving it with the added performance. My ZZ came with a intake similiar to the LT-1 and I was able to use it with a Holley double pumper and Corvette open element air cleaner.

[paul harrington]

Re: C1 Crate Motor Swap

Terry. I put a 383 stroker in my otherwise stock 61. It was not a GM crate motor. I had to put a Dewitts aluminum radiator in to cool it, a custom 2 1/2" exhaust to handle the horsepower as well as a centerforce dual friciton clutch to handle the torque and horsepower. If you have a T-10 you don't want to do too many high RPM launches as it simply wont handle the horsepower and torque. Get the largest, stickiest tires you can fit as this Fred Flinstone technology just doesn't mate well with all this power. Having said all that: It's a blast to drive compared with the 283 I pulled.

Good luck, Paul.