Help with build,sc 98 cobra

[b00sted4v]

Alright so i have a 98 cobra, high compression 11:1 with a vortech v1 S trim.
Everytime i get it up to the tuner/dyno it starts to break up at 4200rpms and then around 5200rpms. If driving the car you can feel it almost like it is dropping cylinders.
I replaced everything ignition wise on the car with all new msd brand parts. I m running tr-6 plugs gapped at .032(should these be tighter with the high compression)
Have been up to the tuner 4-5 times with the car and starting to get aggravated after $10,000+ dumped into it.

just looking for some input before I send the car out to a local mustang performance shop.

Also before the engine and tranny build the car just had a v1 s trim with bassani x pipe with cats and ran perfect, going 12.6 @ 117 mph @ the track on bfg street tires

 

[01yellercobra]

Try gapping the plugs to .024-.026". Given your compression you might need to go down to .022".

And find a new tuner. Closing the gap should have at least been mentioned.

 

[b00sted4v]

yes, will give that a try, had it at performancedyno (pete) in nh who is suppose to be very good.

 

[encasedmetal]

as I responded in the sn95 section. I think it's detonation. to break up in 2 separate places, and not be fixed with a BAS at only 5psi?

 

[98 Saleen Cobra]

What fuel are you running?

 

[Senator]

+1 to what fuel and injectors, and what did your AFR look like?

I fouled out a set of TR6 plugs before my first dyno when I went to bigger MAF/injectors because my AFR was super rich.

 

[b00sted4v]

60lbinjectors, 255 pump, bap, bas

 

[b00sted4v]

car was on 93 pump.

 

[b00sted4v]

dyno sheet

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[b00sted4v]

engine was 180-185 thru every cylinder, i pulled a coil and wouldn't even throw a check engine, or if i disconnect maf or anything with the scanner on it it never signals a code. hmm wonder if something wrong with computer.