How do I get the studs on my rockers to quit breaking, is there too much motor for these heads

BG1442003

MEMBER
1971 CHEVROLET CHEVELLE
82,300 MILES

582 dart block, world products heads, solid lift cam 780-790 lift, 10.1, 700 hp, approx 700 fpt fpt. Dyno tuned on motor. Can take it back to builder but long way away . Would like to fix myself, sounds to me as though he has either wrong springs in there or studs are too weak. Thanks for the site! Used it yesterday to change a belt on a diville. So much help with the pdf file. Ill learn to draw these things out before I rip into them !

2 Replies

CARADIODOC

MECHANIC
33,742 POSTS

.780 lift! That's double of normal. What's in there for rocker arms? If you still have the standard 1.5 to 1, you might consider dropping the cam to a lower lift and going with 1.6 to 1 rocker arms to get the same valve opening.

Regardless, this is typically caused by coil bind when the valve springs are fully compressed and need to go more, or it's from excessively strong springs to prevent valve float at high rpm. With a valve fully open, see if there's room to slide a feeler gauge between the coils. If there's not, back the rocker arm nut off a little. With solid lifters, they can't bleed down like hydraulic lifters so you'll have to live with the clatter. There may be dual springs available that have thinner coils to allow more clearance. The inner spring is a regular spring instead of the wound-up strip used to dampen vibration.