882 heads

[jamie2370]

I swapped from 993 to 882 heads on my nova. Same rockers and pushrods but now rockers are trying to push off the side of valve. Am I correct in saying that guideplates are legal now?

[rboyle]

Guide plates are legal double check pushrod length too though.
Someone else might have other items to check

[Roberte]

Installed valve height, spring o.d.,, length and press.

[Mike Taylor 3601]

trying to push off side of valve as in left/right(front/rear of car) ??? if so use adjustable guide plates.... they adjust side to side separately, so you can center rockers, side to side on valves... drill pushrod slots to1/2' in the heads or guide plates won't be doing anything to locate rockers.....
if talking off tip of valve as toward intake or exhaust side of heads... then you are talking geometry... pushrods too short/long... wrong pivot point rocker(AKA wrong rockers...

[Alan Nyhus]

Originally Posted by jamie2370

I swapped from 993 to 882 heads on my nova. Same rockers and pushrods but now rockers are trying to push off the side of valve. Am I correct in saying that guideplates are legal now?

As Mike Taylor posted...make sure the push rod holes in the head are large enough to eliminate any interference with the push rods. For adjustable guide plates, Jomar's are really nice. They don't move when you tighten the stud.

I assume you're using a spring like the PAC 1409X? If so, a 5/16", .105 wall push rod will work but a 3/8" .080 wall is better. You'll gain you a little lift (due to less deflection) so make sure and check this if the cam is close with smaller push rods.

https://www.competitionproducts.com/...products/2262/

[jamie2370]

Originally Posted by Alan Nyhus

As Mike Taylor posted...make sure the push rod holes in the head are large enough to eliminate any interference with the push rods. For adjustable guide plates, Jomar's are really nice. They don't move when you tighten the stud.

I assume you're using a spring like the PAC 1409X? If so, a 5/16", .105 wall push rod will work but a 3/8" .080 wall is better. You'll gain you a little lift (due to less deflection) so make sure and check this if the cam is close with smaller push rods.

https://www.competitionproducts.com/...products/2262/

Alan, not beehive springs, just standard. From my research it appears someone drilled out the pushrod holes to where a 1/2" drill bit is loose in them, evidently when the heads were originally "worked". I know really nothing about this engine other than it was "supposed" to run 3-4 tenths under. So far I have gone from 3 tenths over to 5 tenths over lol. Hoping by getting the rocker situation fixed it may be closer to what its supposed to be. Guess we will see.....

[Mike Taylor 3601]

pushrod holes were drilled and no guide plates... that will do it every time LOL
maybe had rail rockers before? they have groove or roller version has washer like pieces on each side of roller to keep rocker lined up on valve tip...

[jamie2370]

Thats what I figured. Thanks Mike. They were a spare set I got with the car and did not have studs in them. Guessing they robbed the studs and plates lol. At least they left the Ferrea valves lol