hallgren87idi
Registered User
So this Is bugging the hell out of me. My buddy and I have been putting together a 1988 5.0 roller engine. Stock engine, HEI distributor, put a b303 grind camshaft in from a local cam grinding shop, and a set of better valve springs. Here is where it gets weird, everything is in the car it runs, has oil pressure, but only runs on 4 of 8 cylinders. Compression ranges from 175-185 around all 8 cylinders. Intake manifold was sealed, took that off once to verify, after spraying everything that could have been a vacuum leak with ether, and finding no leaks. Thought maybe we needed longer pushrods so we got longer ones after checking with an adjustable pushrod. No change after putting the intake back on with different pushrods, checked for leaks again none. Got pissed and loostened the intake and pulled the driver side cylinder head to check for a head gasket leak. Couldn't see anything to say for sure it was leaking, but didn't pull the other head and check that one. Pulled the valves out of the two cylinders that didn't fire they were all carboned up, so we cleaned the seats with sandpaper and the valves were pitted. One thought is a combination of water leaking into cylinders could kill them, and maybe the pits on the valves are causing them to not seal? But then why such good psi?? This is really ticking me off Auto swap meet is coming up this weekend, I'm gonna try find a different set of heads with screw in studs so I can have adjustable rockers. The guy helping me is a chevy guy and this is my first build we are pretty stuck. It should run on all 8, we tried a new set of plugs no change. Maybe the wires are bad, nope put a plug in and ground the plug and it sparks. So we really don't know other than the heads must be junk, or head gaskets. But I don't wanna try new head gaskets and bolt on a set of heads I am unsure if they are even good.