I just got done, Converting my 87 305 TBI motor to an 87 TPI induction. I rebuilt the entire motor first. Specs are 315ci, 10.54 compression with Wiseco forged flat tops. Moly rings, 1.7 ratio Crane gold race roller self centering rockers, Crane cam, springs,retainers and keepers. ported and polished factory 1987 GM heads with screw in studs and new stainless steel valves. and finaly the entire rotating assemlby was balanced. My question is this. Before the conversion, the motor began making a ticking noise at 4000rpm and higher sounded like the whole valve train went loose all at the same time. So I tore down the top end to check the valves and guides. The guides were pretty well shot and a few of the valves needed replacing. So it was at this time I decided to go ahead with the rebuild and the TPI conversion. The good news is the TPI conversion was a success. The bad news is that damn tick is still there except it appears at 3000rpms and higher instead of 4000. Could this noise possibly be realted to poor timing and or cold plugs. I havent quite worked all the bugs out of the TPI conversion yet. But it starts and runs great, except for the ticking noise. I wanna say it's pingin but damn if that aint the loudest ping I've ever heard. sounds more like loose rockers. Do ya think changing to hotter plugs might help? Has anyone had a similar problem? heres some eye candy for ya.