I don't have an Evo yet, but I have been doing alot of reserch on the car and everyone starts using 100 octane at like 350+ whp. Why is that My gti made 540 whp at 29 psi, on 94 ocatane. Race fuel is expensive and I don't understand why this fuel is important in these cars. Is it a tuning issue with the stock ecm, a poor cylinder head, or piston design. There has to be away around it, or is there no way around it. Maybe I am reading all the wrong threads, but the first thing I would do is order a stage 3 Buschur kit, if you order 4 you have to use race fuel, nothing against Dave and his team or the other tuners but I just don't get it. I think it is complete BS. Is it possible to make 500 wheel on pump gas?

 

Who said you have to use race fuel to buy BR stg4??? People use race fuel so that they can run much higher boost without knock. I don't know what sort of turbo you used to make 540whp, but whatever you did on 94oct could have been increased by probably another 100whp on race gas. Higher octane provides more knock resistance, thus allowing you to rune insane boost levels with aggressive AFRs and timing. No one has ever said you have to run race gas on an Evo, but with big turbos like the GT35r, you will never get the full potential of it without using some high octane, because it shines above 30psi. With pump gas, you have to keep the boost in the 20s, where it is only so-so...

So, to answer your question, yes, it's possible to make 500whp on pump gas, but it would take a big turbo with some great tuning and a lot of lag unless you have a stroker. That is, of course, unless you refer to having alky injection as "pump gas." With pump gas and alky, you can crank up the boost like race gas...

 

also keep in mind it takes a lot more effort to make 500 wheel horsepower on a 4wd 2.0 liter car than it does to make 500whp on a 2wd 3.0 liter car.

that extra effort means much more aggressive fuel and timing maps.

 

500AWHP has been done on a DSM with pump gas so I am certain it could be done on an EVO. Whether that is practical or not is another matter.

 

I usually mix 100octane with 91 at the track to be safe. I do it to prevent detonation, especially on a road course.

 

I have a 5 gallon mix of 115 with my tank of 93 (10% ethonal) right now. I usualy only do it for weekend though when i'm more prone to WOT. It's a good way to stay on the safe side as i make no adjustments for boost when i do this. Blew an engine once, don't want to do it again.