@FiveLeeter918 I don’t have my laptop in front of me at the moment but iirc 20 psi, depending on the conditions,~12 degrees advance at 3500 rpm. I think you probably missed the part where I said 20 psi at lower rpm in my earlier post? You also missed me saying E40 so maybe it’s just you not paying attention that is the cause of contention. It is important to note 3500 rpm for several reasons-
1) Obviously MBT is much lower at lower engine speeds, so trying to use my 12 degrees as any sort of reference against other, peak advance figures would be useless.
2) at that speed and a load of 2.0, we’re talking about 32 lb/min airflow. With an effective compression ratio somewhere around 2.5:1, I’m literally running the turbos at their absolute peak efficiency at that point. Maps aren’t “one thing”, they are everything in analyzing turbo performance. More useful work = less excess heat = naught a maussive heaat paump!
3) At 32 lb/min the intercooler effectiveness is naturally quite higher than at, say, 45 lb/min, which even further squashes the notion that I’m pumping pure hellfire into my engine.
4) I think somewhere around 4000 rpm is when the engine starts catching up to the turbos and 20 psi is no longer even possible. So during a 3rd gear pull I’m operating there for maybe two seconds. In a real world drag race scenario it only lasts a split second in 1st gear then is never seen again for the rest of the run. The only way to analyze the heat output there would be to hold it in steady state on a load bearing dyno. But again, we already know the turbos and intercooler are both doing their absolute best work at that point so it’s not worth contemplating.
So all of that being noted, my IAT2 “at 20 psi” is really determined by heat soak only, usually 110-130 degrees. At the end of a pull 130-140 is normal iirc. I have definitely seen higher in some conditions but again it has absolutely nothing to do with the 20 psi number you guys are fixating on. The only reason I mentioned the 20 psi in the first place is because that is where the Hpfp is most stressed, making it extremely relevant to the actual topic of this thread.
1) Obviously MBT is much lower at lower engine speeds, so trying to use my 12 degrees as any sort of reference against other, peak advance figures would be useless.
2) at that speed and a load of 2.0, we’re talking about 32 lb/min airflow. With an effective compression ratio somewhere around 2.5:1, I’m literally running the turbos at their absolute peak efficiency at that point. Maps aren’t “one thing”, they are everything in analyzing turbo performance. More useful work = less excess heat = naught a maussive heaat paump!
3) At 32 lb/min the intercooler effectiveness is naturally quite higher than at, say, 45 lb/min, which even further squashes the notion that I’m pumping pure hellfire into my engine.
4) I think somewhere around 4000 rpm is when the engine starts catching up to the turbos and 20 psi is no longer even possible. So during a 3rd gear pull I’m operating there for maybe two seconds. In a real world drag race scenario it only lasts a split second in 1st gear then is never seen again for the rest of the run. The only way to analyze the heat output there would be to hold it in steady state on a load bearing dyno. But again, we already know the turbos and intercooler are both doing their absolute best work at that point so it’s not worth contemplating.
So all of that being noted, my IAT2 “at 20 psi” is really determined by heat soak only, usually 110-130 degrees. At the end of a pull 130-140 is normal iirc. I have definitely seen higher in some conditions but again it has absolutely nothing to do with the 20 psi number you guys are fixating on. The only reason I mentioned the 20 psi in the first place is because that is where the Hpfp is most stressed, making it extremely relevant to the actual topic of this thread.
. But in all seriousness I bet you probably could lightly drive any gas/E10 tune with up to E60 before you ran out of fuel trim and actually started having driveability problems.
