Need help

[rb68rr]

What's going on when my car runs the same times at 20psi as it does at 24psi ? What would cause this?

 

[TurboBuRick]

Could be lots of different reasons.

Did you add more fuel to the wot tune?

 

[rb68rr]

Yes I did. My wideband showed 11.4 at the traps. Looked like the tune was good, just didn't respond to the added boost!

 

[Joe 1320]

Just a few ideas......

At some point, raising the boost increases the heat of the incoming charge to where the resulting temperature increase negates the addional pressure. A better intercooler would help here. The other possibility is that the engine has a bottleneck somewhere in that it can only accept 20 psi, the other 4 psi shown in the intake manifold simply doesn't make though the motor. Better heads and exhaust helps here. Could be a bunch of other things too.

 

[rb68rr]

Others here run equal amounts of boost with similar intercoolers. What bottlenecks are you referring to. Confused. This combo should do better!

 

[rb68rr]

Ttt

 

[Joe 1320]

Can we assume stock heads?
Any knock/timing retard?
Cat in place or open cutout?
Lots of variables......

 

[rb68rr]

Stock heads, no knock, no cat. Last week it ran 7.93 @ 85mph on 20lbs of boost and this week it ran 8.04 @ 86mph on 24lbs of boost! Same 60 ft times and the temperature was the same! I don't get it!!!