dwinhofer

I have a 1985 chevy 350 block that I am going to build up for my 1964 El Camino. I just picked up a set of Vortec heads off of a 1998 chevy pickup. Casting 062. I want to rebuild the heads, but I would like to know which rocker arms to get for them. 1.6 or 1.5. The engine is going to get a lunati cam otherwise the bottom end is stock. Is there anything else I need to know about this build with vortec heads and vortec intake.

maxxman04

depends on the cam lift. stock rockers are typically 1.5. if you're using the vortec injection intake and computer, i'd say stick with the 1.5, unless you plan on running a high lift cam, which the computer may not like anyway. as far as anything else, i would swap out the injector unit, also known as the "spider". stock uses poppet nozzles at the head instead of actual injectors. the injectors are all centrally located in the intake. there is a conversion that eliminates these problematic poppet valves and puts the actual injector at the head, essentially making the normally central port injected vortec into an actual multi-port injected motor. kit can be had for around $300 from oreilly's auto. no matter where you get this kit from tho, make sure you buy the new bracket. it's real easy to install. took bout 3 hours on my 98 tahoe with motor still in truck. good luck.

Terry Neff

The intake from the earlier engine is a 12 bolt intake and the one from the later one is 8 bolt.Don't think the exhaust manifolds interchange.You would have to have screw in rocker studs for the later heads.I suggest you go with 1.5 for rockers.(just to keep it simple)With 1.6's you might have to have the heads machined.Should check that with your machine shop.

You do know that you are mixing newer heads that are designed for a hyro roller cam,with a engine that is a flat lifter.

As I think of more,I will post it.

maxxman04

as stated tho, he is using the vortec intake with the vortec heads. and, there is flat tappet to roller lifter conversions readily available.

Terry Neff

The roller cam conversion kit for his consideration:

http://www.carcraft.com/techarticles...ock/index.html

dwinhofer

I am going to use a edelbrock rpm airgap PN 7501 intake and a Comp Cams XE268 camshaft and lifter kit. The flat tappet camshaft has a max lift of 0.480 inches. I am also going to use a edelbrock 750cfm carburetor. I will need hardened pushrods and I am hoping to get 350 hp out of it. I wonder if there is a little bit bigger cam I can use and have everything else still work? I scratched the lunati cam because of too much lift. I will also have headers and dual exhaust. I will also stay with 1.5 rockers.

72c10gunn

The rocker arms need to be self aligning unless you use guide plates, also there are spring and retainer kits that fit vortec heads and alow more lift(most kits alow about .550) without machining, im in the process of building a vortec headed motor but im using the hydalic roller xr276hr on an oe roller block( i hope for around 400hp out of mine). I think you will reach your 350hp mark with that combo, good luck!

dwinhofer

Are you going to do any machining to your head with that cam? what spring and retainer kit are you using and also what kind of pistons are you using? I have flat tops in the bottom end of this motor.

72c10gunn

im using spring 26915 and retainer 787 with this setup the valve to retainer clearance is around .560 and requires no machining of the valve guides, im also using flat tops.