I recently had a Kraftwerks C38-91 kit installed on my AP2 and got the car tuned at Church Automotive Testing.

The car made 383 whp / 278 wtq - SAE corrected (a bit low?) @ 16.7 psi on 91 pump gas. I'm using the default 90mm pulley and revving to 8300 rpm.

I had about 300 miles of street driving and ~20 miles of track driving and the car ran pretty smooth aside from some major heat issues at the track.

Today, while driving it at night, the car would not rev beyond 7700 rpm (ignition cutting out). Thinking it was maybe a bad tank of gas, I topped it off with fresh 91 from a different station. I took a friend out for some pulls and it worked fine. About two hours later, I took another friend out and it started doing the ignition cut @ 7700 rpm again.

What is the car detecting that could be causing that?

Here's my setup:
Supercharger: Kraftwerks kit w/ Rotrex C38-91
Engine: F22C, stock
Injectors: ID1000
Fuel Pump: Walbro 255
EMS: AEM EMS Series 2
Fuel: 91 Octane
PSI: 16.7
WHP: 383 whp
WTQ: 277 wtq
Dyno: Dynapack
Additional Specs: Mugen AP2 header, T1R 70mm headerback exhaust