Flash for HPDE car with spray & pray


Aug 31, 2019
135i, 335i, x5d, r53
Looking for a tuner or advice on my HPDE 135i, 2008 135i MT that is FBO inlets/outlets/meth with JB4 BEF race map.

I'm going to go back to flash only with a simple water/meth controller via PSI, full spray at 8psi to control IAT on track. JB4 keeps overheating in 3rd and 4th sessions and shutting off / restarting while I'm on the track. Works great while it's cold but on a hot day in the afternoon it craps out. Partial throttle load is not as smooth with the bef/jb4 either. On top of that the jb4 wont let me obd2 data log on my racecapture mk2 pro.

Any tuners experienced with this? I need more timing, 1M throttle buffer, linear throttle pedal I currently run the race fuel bef Map3 and 75 adder to hit 20PSI with the jb4 and rely on the jb4 safeties so the flash tune would need to watch and pull boost or timing via IAT if the methanol stops for any reason, basically more aggressive IAT power reduction tables, I do this with my R53 mini's and it works really well.

prefer unlocked maps so I can adjust idle/throttle pedal table / and throttle buffers however it's not a show stopper as I have settled my current tune changes and I'm happy


New Member
Apr 7, 2021
the free RFP tunes will get you around 21 psi and tapering down from there. it should be a good start if youre looking to tune it yourself