'92 1.6 begi shanghai S cuts out at 4k rpm
 

Car of a buddy of mine is at a dynoshop to get his MS sorted out. Problem is, car cuts out after 4k rpm. According to dynotuner dude, the car then has 120whp @10 psi. It's not overboost protection kicking in (set at 255kPa). Tune so far doesn't look weird to me (for a tune in progress). Any ideas?

Car is a 92 1.6. Begi Shanghai S with T25/T28 turbo, mild steel separated gases downpipe, full 2,5" catless exhaust, Innovate LC-1 WBO2, MSPNP 90-93 running MS1 029q code. RC 440cc injectors.

Current .msq attached, no log file (yet).

I suspect it has something to do with the fact that you're running only 6 degrees of spark timing at 10 psi.

Little update: apparently, tach drops to 0 after hitting 4k rpm and then comes back. They are suspecting coils or igniter and are sourcing a replacement.

If you could post a data log, that would be great.

regap the spark plugs correctly and advance the timing.

Take the car to a different dyno shop if they are that clueless.

Little update: fresh coils apparently solved the 4k cut out. They also said the fuel pump was dying and they put in another one. Car now has 180-ish whp at 14.5 psi. Detonation is (was) present and timing up top is only around 6*. I feel more should be possible on this setup without detonation occurring.
This is what I'm told, so what gives?