Gojira94

iTrader: (4)

Fuel pressure is normal. That looks fine. What top end mods do you have? I see cam, but which cam? Which rockers & springs? You might end up having to log it and see if you're getting a ton of retard at WOT. Also, what plugs are you running and where are they gapped? Have you worked out your SCR, especially since you must have switched head gaskets and had the heads at least mildly resurfaced to get RA of 50 or better... sounds like something isn't happy in the valvetrain or it's pulling timing like crazy for some unknown reason. Tune? knock desensitization or LT4 KM at least?

1997transamman

im not exactly sure what yous talking about the src? i have never heard of that. it has new fuel pump and regulator. the engine is bone stock except boltons. no cam, stock springs and all that. all i did was tak the heads off clean them up and put the new gaskets back on then heads on. nothing charged thats what i dont understand

Gojira94

iTrader: (4)

SCR = static compression ratio. If you're all stock and used stock Victor-Reinz or equivalent Fel-Pro head gaskets (.046" compressed thickness I think ?) then you're still at 10.4:1. Was getting a feel for whether you had picked up some compression and were detonating or picking up knock/retard. What bore size gasket did you use? Part number for the gasket might shed some light on it. Did you reuse the head bolts or get some new ones? Retorqued them after a couple hundred miles?

How about the plugs? What plugs are they and where do you have them gapped?

Just throwing some ideas out there...

1997transamman

i used felpro 9966 head gasket set. they are just stock replacement. yes new head bolts. yes retorqued. i have had autolite 103s and ngk tr6 both in there. the ngk was in there when i got the car with no missfire. thats what i put back in it. thought maybe one was bad so i put the autolites in. both were gapped at .50 (factory specs)

mguidry629

iTrader: (6)

I thought .035-.045 was normal gap. 50 seems a little high, but probably not you're problem.

You really need to datalog it at this point to see if you're getting a lot of timing taken out because of detonation or false knock..

I would always get a head milled after a blown head gasket cuz it's probably warped.

1997transamman

i will be hooking it to a tech2 tommorow. what kind of data should i be looking for? i will post up everything on here. i know i always get the heads redone when i have them off but time and money was a problem at the time.

Gojira94

iTrader: (4)

See what happens to the timing when you go WOT and see if your knock counts spike anywhere between 4000 & 6000. May not be either one but two good things to eliminate.

.050 is correct gap for plugs on a factory HP, 10.4:1 engine. A loose rule of thumb is to close the gap about .004 for each 50 crank HP above stock. And move to a colder heat range plug (stock is heat range 5), i.e. NGK TR6 , heat range 6 (higher is colder) for engines above 11:1 SCR and even colder like heat range 7 for some nitrous applications (which benefit from a shielded plug tip as well).