Just want to know whats the Max boost that could be run on 98 Octane?????
Currenctly on MR Turbo with other supporting mods running 1.7 bars on striaght Pump Gas.
PPl here are running 1.8 Bar on Apexi Rx-6 on pump gas...
So any chance i could run say 1.8 on my GT35R on on pump gas????

 

I think compression ratio, charge temps, fuel type, ignition advance, etc all effect the max boost you'd be able to run. So I think it is hard to say. When you say 98 octane, do you mean RON or PON?

 

Static compression ratio is obviously a huge factor that is often overlooked and seldomly discussed. Unless noted otherwise, we assume you are running stock CR (+/- 0.1).

I recall one individual here with stock CR, tuned to run 1.9 bar with 98 RON, and reporting unusual spool characteristics for his GT series turbo, but with power levels typical of others using ~1.6 bar. When we delved further into the matter, he reported EGT of 900C.

U.S. 93 is roughly the equivalent of 98 RON. If you want to explore the limit of fuel octane on the dyno, raise the boost 0.1 bar at a time, while adjusting ignition advance to the onset of detonation. Record the difference in power, and use the lowest boost setting required to attain the best power level. In my case with a GT35R, similar equipment and stock CR, this worked out to be around ~1.6 bar and ~455whp (DJ).