I am building a new 383 chevy engine. I have a set of the new Edelbrock aluminum heads that i am going to install. My question is this, nearly every head manufacturer states that you must use 0.100 longer pushrods when installing their heads if they are aluminum. Does the Edelbrock RPM head require the use of the longer pushrod? I know how to check for the correct length using the magic marker technique but do i need to go ahead and order the longer rods and have them onhand so my engine building will not get held up???

I used them on my 383 with RPM heads. I think that it says that you have to use them in the directions.....or is it dependent upon the rocker arm type?!?! I used roller rockers and they said that I had to use the longer hardened pushrods. I think in the end it's all about the rocker arm geometry though.

Check the instructions that came with the heads. I just put a set on my 350 and it required the longer .100 HARDENED push rods. Even with roller tip rockers. Be sure to get the hardened rods for use with guide plates, and check all your rocker tips on the valve side for centering on the valve stem before you fire it up. I cycled the valves by hand cranking the motor several times to make sure nothing was binding or rubbing.

Yes you do need .100 longer push rods. Thats according to the instructions that came with mine.

Thanks for the help guys, My heads did not come with any instructions, thanks again.

When I installed my Edelbrock RPM heads, the best rocker arm geometry was achieved with stock-length pushrods. My combo uses 1.6 intake rockers and 1.52 exhaust rockers. I recommend checking geometry before buying new pushrods.

I used roller rockers on my 383 with edelbrock heads and they lined up very well on the valve using stock length pushrods. I was able to check them with a stock pushrod before buying hardened ones. I will say one thing I was not happy with on the RPM heads was the clearance between the pushrod and the head. I had to spend a lot of time ligning up the guide plates.

Originally posted by Beau's 67:
I had to spend a lot of time ligning up the guide plates. Same thing here, and there isn't a lot of clearance now (.015)

I used stock length hardened chromoly pushrods from Crane, Comp Cams Pro Magnum 1.52 rockers, and they are just right.

After 10 years, no problems.

I was able to run stock lenght pushrods with my performer rpm heads. I used 1.5 roller rockers and I installed the rpm camshaft if that makes any difference. I spent alot of time trying to get the guide plates to line up as well it was kinda scarry seeing how close the pushrods come to the intake port wall.

I do like the shorter gasketed plugs that they call for, makes changing the plugs alot easier than before.

I have not got my engine running yet. It's together and in the car. The question that I have is are you losing anything lift wise in the cam with the stock pushrod length?