What do you guys think?

[5LVENOM]

First off, it is a stock 95 cobra longblock with an E-cam. 70k miles well maintained. Did headgaskets, valve seals, and valve springs before tune day abouyt 6 months ago. Puts down 389rwhp, 403 rwtq, at 5k rpm, blew out the spark. So since then I put on the 6AL, and called it good (MSD blaster, FMS wires NGK cold plugs). Its been running good, took it to the track a few times etc. So the other nite I was cruising, and I hammered it pretty good (first time with the DRs), and bounced it off the 6k pill in the MSD, and as soon as I let off it was missing BAD, so I went home, and its been sitting for a week. Today I pulled the plugs (figured I fouled one), they looked good except #7 was black as hell. I changed the cap, rotor and plugs, it still misses like a *****. Tomarrow I will get some new wires and maybe do a comp. test. What else could it be? I hope I didn't wipe out rings, or put a hole in the piston, my tune was safe, with 11.7-1 A/F, and 17* total timing @ 10 psi, and it has the GT-40 irons on it still, 42s no FMU, 255 in tank, T-rex in line, adj.FRP@ 40psi, etc. Please help, what else should I check, before tearing it down? Thanks, -Rob

[V2-SQ Jess]

valve spring ? do a comp test on that cyl.

[5LVENOM]

Doing a comp. test today, I'll let you guys know what I find.

[5LVENOM]

Compression in #7 is 0 psi. I'll be tearing it down to inspect the carnage, but it can't be good. I'll keep you posted, looks like 331 time.

[V2-SQ Jess]

just take the valve cover off. if its just the spring, and you can find all the pieces, it should just be broke in half = no little pieces. just replace that spring. don't even need to remove the head.
been there done that.