VP M3 vs M5 A/F

Hey,
We used M5 and russian industrial meth, both showed a fuel burn.
Last race we used M3, and no fuel burn, ground strap was as usual. Took 10% of fuel out, cooler air in the evening, but still nothing.
Power was off by 300 hp: 1400 -> 1100
Humidity 50, heat 100+ hp ok, so the fuel killed 150 hp ???

Plugs 5671-9

Thanks,
Partel

 

VP told me to give it 3-5% more fuel, but I haven't tried it yet.