Got a 99 Gt with a P1sc, Trickflow intake, 75mm BBK t/b, Anderson power pipe, 44lb injectors, Focus fuel pump, Sct xcal2. I make around 400hp, 370tq. My car runs great on the dyno. At the track, 1st gear is good, shift at 6300, 2nd gear is good, shift at 6300, 3rd gear good up to 6200 and falls on it's face almost like hitting a rev limiter(which is set to 6700), I shift to 4th and pulls thru the traps sounding broken up(had this problem all summer). I would occasionally get a fuel rail press sensor fail code. I always have a pcm error code. I researched the pcm code and it seems like a common code with sct xcal's(normal). I first replaced the fuel pump with another. I then changed the sensor itself. It does this with 1/4 tank of fuel, it does this with a full tank! Is it possible I'm running out of fuel? I've also changed the cop's, the plugs(gapped at .035). Has anyone else had this issue? I'm thinking about a KB boost-a-pump, but tired of throwing money at this problem that only happens at the track...at the top of 3rd and thru 4th.
Thanks in advance.

 

Top of third and fourth is where the greatest load is on your engine as the gear ratio approaches and reaches 1:1. Could be a fuel problem. Best way to check is datalog and/or get a wideband o2 sensor and watch your ratio at the top end.

 

That's what I thought too. I can't data log, because my xcal2 doesn't want to connect to my new Vista laptop[sm=shootshoot.gif] I figured the engine would have nuked by now with all stock internals if running that lean on top.As soon as power drops offat 6200 rpm's, I shift to 4th, and it runs like crap all the way thru.

 

yea, sounds like your pushing about the same h.p. as me. i was toldat my last tune that i need to upgrade to 03-04 cobra tank and dual pumps. and fuel rails. its just really expensive.

 

you're maxed out at 400RWHP? i was maxed out at 467RWHP with 36lbs injectors & my 255lph pump. i upgraded to the cobra setup and it wasn't all that much. especially if you get a used tank & pumps.