after 5000 miles on the rebuilt motor,i pulled the valve covers to check hydraulic lifter adjustment.i found the #3 rocker wasn't sitting straight on the valve tip,and the valve tip was
"mushroomed" and pretty chewed up.after pulling the rest of the rockers on the passenger side i found similar mushrooming on the #3 intake and both valves on the #4 cylinder!the motor has only seen 5000 rpm a few times.the timing was found to be too advanced when a new balancer was installed.
could detonation cause this?the engine rotated freely when the cam was installed.
i will pull the rockers on the other head,and check the pushrods for straightness tonight,and try to get some good pics to post when it's light out.
thanks in advance for any advice or suggestions anyone might have!
86 camaro,383,topline vortecs,scat crank,wiseco forged 9.5:1,6"scat rods,comp xs282s,performer rpm,750 proform vac sec,msd in cap, hooker coated 1 5/8"headers,3"flowmaster,700r4,2800 stall,3.42 10 bolt posi,hotchkiss lca's,aje tube k member & a-arms