How Much Boost?

[5150]

ok guys i've looked but cant seem to find an answer so here it is, I have an Mitsu 18g, Denso 660cc, AFPR 1-1, FMIC, WALBORO 255lph, and some other mods on stock internals. But my question is how much boost can i run safely? Originally i was thinking aroung 22psi but now im not quit sure. Any help?

 

[daren_p]

That is a question you have to answer yourself, get your logger out, do some pulls at lower boost and start increasing it till you knock. Every car is slightly different & the octane you run will have an effect. With everything being good, 22 psi would be in the ball park, plus or minus a couple psi depending on your perticular setup.

 

[JayRolla]

What he said ^^^^^^^^ You just have to start low and tune tune tune. A wideband would help out a lot or bring it to a dyno. On pump you should beable to push 18-22psi with a good tune.

 

[5150]

Well i dont have a logger i was planning on getting DSMlink for my fuel control, and i heard that you can do the same thing with that, is that true.

 

[aero_sallee]

Well i dont have a logger i was planning on getting DSMlink for my fuel control, and i heard that you can do the same thing with that, is that true.

Yes. If you can afford it.

 

[black91awdturbo]

if you have no way to controll those 680's your car will run like crap, at least get a safc to controll them.

 

[JayRolla]

You have no fuel control and you think you can run 22psi. No way man take those injectors out and run 12-14psi untill you get the thing tuned. You will just cause damage to the motor.

 

[scottsee]

We just went through this question in the Tuning area. Boost shouldn't be your goal. Airflow is what makes power. For quick refrence 660's will supply the following ariflow assuming 43bfp, pumpgas and a properly working fpr that isn't being overrun from a 255..

9.5:1 = 41lb/min @ 79% IDC
10:1 = 44lb/min @ 74% IDC
10.5:1 = 46lb/min @ 71% IDC
11:1 = 48lb/min @ 69% IDC
11.5:1 = 51lb/min @ 65% IDC
12:1 = 53lb/min @ 62% IDC
12.5:1 = 55lb/min = 60% IDC

http://www.dsmtuner.com/forums/showthread.php?t=235939

 

[daren_p]

If you have no way of controller those injectors yet, don't install them. They will cause you to run extremely lean. If the car does run, it will run like crap and you are takeing the chance of doing motor damage from washing the cylinder walls since you will be dumping so much fuel. Kepp the boost under 14 psi until you get the fuel system/logging/tuning taken care of.

 

[5150]

Ok i apologize for causing a panic i guess i should of said this earlier, the car does not run right now the motor was rebuilt and i am awaiting on a auto tensioner before i can start it. The Dsm link will be my fuel control as soon as i get paid.

I was just trying to figure out a general are of were my boost should be.