Push rod holes in Eddy aluminum heads

[69_340_GTS]

Does anyone know for sure: If I put a hydraulic roller cam & lifters in a 340 with Edelbrock Performer RPM heads, will the pushrods wind up rubbing in the pushrod holes? I've heard "yes" and I've heard "no". I really don't want have to take the heads off and get them machined. Thanks!

 

[OldmanRick]

How much lift does the new roller cam have? If it's big, and with the retro lifters & probable shorter pushrods, I'd lean toward yes.....as possibly causing interference.

 

[340sFastback]

I run hydraulic roller with eddie heads and even with 5/16" push rods they needed a lot of clearancing. .590" intake and .550" exhaust lift.

 

[69_340_GTS]

Cam has .535"/.531" lift, 268°/276°. It's a Comp XR268HR-10. I have Hughes hydraulic lifters. Just don't want to take the heads off! But if I have to, I will... Thanks again.

 

[jbc426]

Mine fit easily without clearancing them, but its a smallish cam. I'm running the 1.65 to 1 Chevy rockers from Hughes.

 

[69_340_GTS]

Mine fit easily without clearancing them, but its a smallish cam. I'm running the 1.65 to 1 Chevy rockers from Hughes.

Those look like Magnum heads. I think that's why you had no problem.

Is there an answer?

 

[crackedback]

Those look like Magnum heads. I think that's why you had no problem.

Is there an answer?

Mock it up with checking springs and see what you get.

What worse, doing while it's on a stand or after you've installed/fired it in the car.

The two that I've had, both needed material removed.

 

[rumblefish360]

I do bieleve the standard heads will need a bit of dill/dremal work to clear the pushrods holes.

 

[1970Duster]

La based heads need Pushrod work to use a roller cam. I know this because I have a roller cam in my 340 with eddy heads.

 

[jbc426]

Those look like Magnum heads. I think that's why you had no problem.

Is there an answer?

Yes, they are. Sorry.

 

[69_340_GTS]

Thanks everybody.