(couldnt find a thread) Currently im running 23 PSI on 93 with full bolt on and an ETS turbo kit, how high can you boost before you have to sweat it? and is there a noticeable difference in lets say 23 psi and 26?

 

Depends on the turbo. I was able to run 29psi on 92 octane with my ETS 3586 and some careful tuning. My car goes from 496whp at 23 to 540s at 26psi, so even if you didnt get super crazy even the next 3psi could make a difference.

 

im running a 58mm ETS turbo, so im not sure what its safely capable of but im probobly going to tune for 26/27 psi and hope my motor can take it, but with ARPs and cams it should be ok

 

Its not boost pressure thats the issue, its cylinder pressure. Timing has a big factor in how much boost your can run, and also what the motor likes or dosent like. My setup gt4294 2.4, and I run 32 33psi on straight 93 pump gas with 13-14 degrees of timing, and my a/fs are around 11.5 11.7 and my knock on aem is 1.5 2.0 max which is usually driveline, and other noise.

 

I am on a stock 9 turbo at 31 psi no knock 12.0 afr and it pulls very good.

 

if you find a compressor map for your turbo, it will tell you where the sweet spot is for increasing the boost (inner area, i think).

if your in the sweet spot, then small changes to pressure will make big changes to power, similar to JohnBradley's example above. Once you get beyond that, increasing the boost will give you diminishing returns. Eventually you will lose power and/or break something.

 

I was wondering the same thing but i was lookin more for reliability over max hp. dont get me wrong i want high hp but i dont want to put to much wear on the engine.

I have an upgraded intake, exhuast, turbo, intercooler, etc. so the amount of boost wont be a problem.

All the internal engine components are stock so i dont want to break something with a stupid amount of boost.

 

Stock turbo on pump I'm running 25-26psi, and I get zero knock until I hit about 7500rpm in 5th or 6th, and then only occasionally get about 4 counts. I wouldn't push much more than that without meth or e85.

 

7500rpm in 6th is like 180 MPH

Stock IX turbo, I run 26.5 peak psi on 93 octane and 29-30 on 110 octane...no issues with zero knock

 

Bump

 

I'd like to know the limit on the stock 4g63 MIVEC motor, and is this the stock motor revving to 7500?

 

I'm pushing it to 32.5psi no higher than 33.7psi in 5th gear.

 

^^^^^ Your car is hot

 

^^^^^Thank you

 

what power did you make?