Just keep thinking that. You would be amazed at what a 4G63T is capable of with the right turbo.

 

Just a reminder...

If your gage reads 2.0 bar you are only pushing 1.0 bar.


Atmospheric pressure = 1.0 bar = 14.7psi

 

just remember the turbo itself has nothing to do with how much boost pressure the engine can handle. That is affected mostly by the compression ratio of the engine. That's why a factory turbo engine will have a lower compression ratio than a normally aspirated engine.

 

No turbo can defy the laws of physics buddy.

 

Of course you can't defy the laws of physics. But what law says that you can't run 23psi on pump gas? In the 10 or so Physics classes I have taken over the years, I can't think of one.

People have very recently been pushing the limits of the 4G63T on pump gas. Depending on the turbo (and complete setup) that is used, 23 to 24psi of boost is not out of the question with 93 octane fuel.

Of course, boost pressure in the intake manifold hardly matters. It is really cylinder pressure that ultimately matters. And with good enough engine management, you can keep detonation from ruining your party.

A few years ago, most people would have said that the 19psi that the Evo (or my car) runs on pump gas is simply impossible. But we all know that it is (though there are always a few hold-outs). In a few years, maybe common knowlege will once again shift.

You just have to get up to speed with what the rest of the world is doing.

 

23-24 psi on 91 octane is quite an accomplishment (maybe you have forgotten pump gas in california, which is what i said, is 91).. let me know when you have achieved it.. make sure to call your mechanic ahead of time..
--bobby

 

I don't even have access to 91 octane. All I can get is 93. Luckily I live in a semi-sane state.

 

Hmmm, pump gas up here is only 91 octane and I can push 25 psi on it daily, pretty easily too. 109 mph and 12's at Bandimere Speedway on 91 octane with *everything* in my car, full street weight.
Now at 27 psi then I gotta make her a little richer to keep the knock down and that's not good. Tuning is everything. At 27 psi I'm actually slower because she's too rich.
But, I have a decent turbo (which Shape did mention in his post, Thanks Josh!) and a decent fmic.

 

I've run up to 26psi on 93-octane gas in a motor that is far more susceptible to detonation than the 4G63. You should NEVER suggest something couldn’t be done, because often you’ll find someone that comes along and does exactly what you said couldn’t happen.

-Nathan

 

Dre runs 22psi on pump gas every ****ing day in his DSM. He's probably pushed out 24psi, again, pump gas only, ever.

I know more than one DSMer has ran 28psi on pump with no ill effects. I think this was on some T3/T4 combo.

Saying you can't run over 23psi on pump gas is just so ****ing retarded. You should be slapped silly for making such unsubstantiated statements. Did you get that from Sport Compact Car or SuperStreet? Please enlighten us with more of your magazine read knowledge.

4G63
38lb/min compressor
24psi
stock fuel system
pump gas
no damage

Learn by experience.

 

yes its great that you can do it nathan aka technical director but the avg enthusiast with no idea what he is doing should not try to run 26psi.. so people with there brand new evos dont go putting on bcs and hiking up the boost just because some people with higher octane gas say it can be done.. i doubt the engine would be healthy at 26psi on 93 octane.. i dont see that as something that can be daily driven and reliable..
--bobby
btw, van that 91 octane and 25psi.. gl

 

Guys, hello, this was never about your cars. This is about a stock evo running 22+psi on 91 octane. Not happening.

 

Maybe you didn't know that an EVO has a 16G'd 4G63. Plenty of us have ran 22psi+ on 4G63 with a 16G and stock fuel systems. But keep talking out of your *** like you know anything about the EVO, 4G63 or cars in general.

 

English, mother****er, do you speak it?

If you were trying to ask if Van runs 91 octane then the answer is "yes", that's what we have in Colorado. Same gas as California.

 

Fabulous, but what you dont realize is that many, if not most of the people purchasing the new evos have no experience with these engines or possibly even cars in general. If you have the experience to be able to do this (although I'm still not convinced) then more power to you. The point is that if everyone hears you can run 22+psi on their stock evo, there are going to be a lot of blown motors. Never underestimate the ignorance of the average person.

Also, I dont appreciate the personal attack, but I acknowledge the fact that uneducated individuals must fall back on this kind of talk in order to make their point.