new to this so bare with me. blew a head gasket so i just put a set of used but resurfaced and tested cast world heads.had some 1.6 comp cam roller rockers and bought new comp cam stock length push rods. only prob was the angle of the 2 center bolts for the intake. ground out the right angle to fit, no leaks and car ran great for about a weak. started running rough. checked the valve train and found a broken spring.replaced it with the head still in the car.car ran great again. got on the gas a little bit started running rough again. no broken springs so i did a compression check all between 140 and 145psi. checked valve springs again just to be sure and found a soft spring(I can push it down by hand.) can anybody help me out with why this keeps happening.

 

sounds like you bought a set of heads with bad springs . if it were me , i would replace them all . just my thoughts , good luck .

 

I have World Heads too. The Springs suck! Several of mine broke the Spring Dampeners and if yours have Umbrella Seals I'd get rid of those too.

 

thanks for the info.will change em all.any suggestions on brand and a easier way to change em curb side without pulling the heads.

 

World spring suck on the low buck iron S/R heads they sell. I broke 5 damper springs with my 4x4 comp cam.

Comp springs are good but expensive. Whats the lift on your cam and is it a roller or flat tappet?

 

stock cam for the GTA 5.7,and their rollers

 

I used Crane 99846 Springs and changed them without pulling the heads. I used an air compressor to hold the valves up.