At least I'm hoping it's simple.

I'm trying to fight off a hump at peak boost that I may not be able to eliminate. I'm using a Hallman Pro MBC which spikes 24psi, and I can't seem to get AFRs to smooth out.

Any help is appreciated.

Here's my info (note the two different tables are for Max and Min AFR:

 

contact 4 wheel slide, he can help you out.

 

can you post a log of a 3rd gear pull from 2k to redline?

 

slightly

Sorry .. just wondering why everyone here is different .. as you guys like to go very rich during spool up ..

note the spool up region for the original map ..

and then note spool up region for the modified map

Most of the evos here (JDM) starts around 13.x AFR tapering to 11.x AFR AT full boost .. but USDM mostly tune for 11.x AFR AT start of boost..

 

if you're running higher timing down there you can't run a lean AFR

 

To the OP do you have lean spool enabled or not?

 

Lean Spool is disabled

 

I try to tune for 12.8 AFR for as long as possible during spool up. I've found it helps spool slightly.

 

Off boost and off vacumm at all rpm points your a/f should be in the high 12's / low 13's, then as you go onto low boost (7psi) it should go into the mid 12's, then as the boost goes over 10 psi it should transition to lower mid 11's towards 17 psi. Over 20 psi then it should dip into the bottom 11's. I'm assuming this is 93 octane, if it's for 100 octane I would leave it in the mid 11's all the way up to 24 psi, then over 24 psi shift down the a/f towards bottom 11's. It's better to run consertive timing with normal a/f ratios than run excessive timing with rich a/f ratios. You can get rich knock, wash the oil off the cylinder walls, as well as foul spark plugs.

 

The reason I was asking that question is so I can help you answer yours

When you go bigger turbo .. you need to know when the turbo starts spooling .. and shift the rpm band I highlighted to the point where it spools (for GT30 it's shifted by 500rpms) ..

Anyway .. from there .. you should see a nice taper from offboost to on boost to full boost ..

The hump is there because the accel enrichment is off ..

Now since you shifted the fuel / rpm band by 500rpms (EG only!!!!) you need to shift the same values in the accel enrichment by 500rpms

I guarantee you that hump should be smoothen out AND you'll get better spoolup characteristics ..