So about a week ago I missed a gear and as a result the engine over revved and coasted to a stop with a trail of black smoke/ fuel following.

We immediately thought to go over timing as it seemed like it jumped. It would attempt to start, somewhat start and over fuel (smelled of fuel heavily in exhaust) sputter and die out. We checked the timing twice and searched around for any other visual signs but found nothing. There were no abnormal noises.

A compression test yielded lower compression across all cylinders (something like 120 120 115 110)

We ended up pulling the head to have the valves checked and they turned out ok with nothing more than normal wear. The cylinders have some wash to them but everything to be expected from the incident and 90,000 miles.

Any suggestions as where we should look for other symptoms/causes?

The mods are as follows:
Titek O2 housing and Megan 3” catback with test pipe
FIC 1250 injectors
Tephra V7
ETS 3.5” FMIC
GSC S1 intake, S2 exhaust cam
Ported OEM exhaust manifold
Injen UICP and intake
ETS LICP
HTA71 turbo with 84mm FP cover

 

Do a leakdown test.

 

Its probably too late for that now that the head is being gone through and I wont have it back for a few days

 

Still hoping for some input or help

 

So does the car not start?

 

1st thing would have been a boost leak test, then a set of plugs

 

The car will start and idle roughly sometimes but not every time. We have already tried changing plugs, they were certainly fouled

 

boost leak test?

 

Just got the car back together after the head was gone through and I'm still not getting much. Car acts as if its out of time but we checked and checked multiple times