boost pressure versus 91 octane

[shawn_robinson]

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Hello every one looking for all the gurus.
I am trying to end an argument between freinds, what would be the most boost you could run on 91 octain with an unlimitted supply of fuel to let say a gt35r turbo
and be able to pull back timming to accomadate detonation . hp loss not being a factor but lets push it to about 500 rwhp no less. this is to make it simple as my friend does not seem to under stand that boost pressure versus turbo efficiency as well as timeing can play a major roll as far as boost pressure. all he seems to be able to comprehend is you cannot run 91 octaine and run 24 pounds of boost,
no matter how much fuel you use to compensate for detonation. I had a 2.3 litre motor fully built to run 30 psi and a turbo efficient enough to run at 30 psi all day long but with 720 cc injectors his claim is I blew it up at 18, well yeah I had my 42 pound injectors in at the time and pushed it to 25 psi da
well any way lets help educate my friend on this or me. how much boost for a gt35r turbo and alot of 91 octaine before she blows

[matt325is]

It all depends on tuning. Depending on engine size, you could probably produce 500whp with a gt35r on 91 octane gas. I've run 21psi on my 2.8l with pump gas, and hit 329whp and 405wtq at 17psi. With more tuning and better head flow, I'm going to get a lot more out of that. I have 80lb/hr (830cc/min) injectors, so I'll be good for a lot of power. It all depends on tuning, but I'd say you could run 35+ with 91 octane, but it also depends on your static compression (you cant run 35psi on a 10:1 compression engine, but on a 8:1 you probably can).

matt

[bmw335ist]

Tunning plays a big part in the production of power
shit you made 405wtq at 17psi.