so my cobra made 601 the first time at the dyno and it recently felt a little slower so i took it back to the dyno. the car showed a little lean so the tuner pointed out some vacuum lines and the way they were hooked up so i re-routed the boost by-pass valve vacuum supply and boost gauge, and the car went back on the dyno VERY rich past 10:1 which is all the gas analyzer could read. we adjusted the tune turned the kb boost-a-pump to 0 and got it back into range.

however before and after messing with vacuum lines and the tune at 3800 rpm every single run it would drop about 30 RWHP and you could hear it in the car and feel it(then the car would continue to pull). tweaked some more with the tune and no matter what its @3800 rpm like clockwork. i picked up some ford coils today to try going back to tuner on sat to hopefully trouble shoot need some more ideas in case the coils dont fix it.

fuel pressure is good MAF volts look good, a/f ratio is good. im not sure what would cause it to be so precise at 3800 rpm.

 

Spark Blowout? What plugs and gap are you running?

 

I'd say spark blow out as well.

What plugs, and how are they gapped?

 

the plugs were ngk tr6 at 35 gap, the problem was the coils i put 2 coils in the passenger side and it fixed it, going to buy all new ford coils to replace the accel coils previous owner had in it. then back to the dyno for re-tune

 

I would gap them to .028 - .032.

.035 is pretty high for F/I Applications.

 

havent had a blow out problem yet but when i do i will re-gap to 32 or so it made 602 rwhp with those plugs in it so should be ok untill they start getting worn down atleast

 

lol, my plugs are gapped at .022

Glad you got the spark issue resolved though! Cheers!