[mainejohn]

Iam installing some new eddy performer rpm heads and i have installed a 488 lift cam, i also have flat top pistons. should my valve clearence be okay?

[cobalt327]

While it should be OK, you'd be better off actually verifying it yourself.

Here's a list of some areas that need to be verified to be OK.

• Springs for installed height

• Coil bind (+/= 0.040” between all coils)

• Retainer to seal/ valve guide boss at full lift

• Retainer to rocker

• Trunnion to stud boss

• Piston to valve clearance (both before and after TDC on overlap)

• Push rod to guide slot in head (if used)

• Can use EITHER self aligning rockers OR pushrod guide slots in head OR guide plates, not two or more of these at the same time

• ”Rails” of self adjusting rockers (if used) to retainer

• Rocker to valve tip (by adjusting guide plates if used)

• Rocker slot to stud (if using stamped/cast rockers w/pivot balls)

• Proper geometry (push rod length)

• Rocker/polyloc to valve cover or baffle

• Camshaft endplay

• Distributor shaft and gear endplay

• Distributor gear material compatible with cam material

• Hydraulic lifter preload

• Timing set phasing

• Cam gear to crank gear alignment

• Cam gear end play if roller cam

• If using the SBC OEM roller lifters and retainers (aka dogbones), lobe lift must be kept below 0.354” so the lifters don’t lose contact w/the retainers

• Cam lobe to connecting rod on strokers

Probably something else I'm missing. But it has to be physically checked, you should not take it on faith or by figuring it out on paper.

[mainejohn]

wow thats scaring me!!!

[cobalt327]

Originally Posted by mainejohn

wow thats scaring me!!!

It looks worse than it actually is. The MAIN things to watch for is getting the pushrod length correct to have the valve train geometry right, and the piston to valve clearance checked to be adaquate. Depending on the exact rockers you use, be sure there's clearance between them and the spring retainers. If you use 1.6 rockers, be sure that this is taken into consideration. If you use stamped steel rockers, be sure the slots are long enough.

But as you go through the list you'll see things that do not pertain to your build.

The other things like open and seat spring pressures, coil bind height and max lift and such will have been published in the specs for your heads. Be sure they jibe w/the specs of your cam and they will be good to go.

[mainejohn]

i am using 1.5 aluminum roller rockers. the eddy heads are factory assembled, and the cam is under .500 so hopefully everything will be okay

[johnsongrass1]

.100 on the exhaust. .035 on the intake.

"HOPEFULLY" you don't waste a $1000 dollars fixing the heads and pistons because you didn't check. Your call.....