Hi,

I have an EVO IX with JUN 272 cams.
Before installing the cams I had street tuned the car and the map was working great with DP/Exhaust/larger IC/intake.
I also did the Tephra mod.

Now with the cams and RC 750cc I did all the fuel trims and they are ok, but I have a problem between 2500 and 3000 PRM.

Basically at those RPMs at WOT the AFR suddendly goes up to 16 and the car bogs, then the AFR goes back down to 12-12.5 and then no problem it accelerates fine.

I have this problem only at these RPM, could it be related to the passage from closed to open loop? Could somebody give me a suggestion as to what values I should try to correct?

I obviously still have to map the car completely after the cam install, but I'd like to solve this problem at first, that way I can start doing some decent logs without the car getting stuck like that...

 

could you post a log?

 

what mivec values you running? If 28.8* I'd suggest lowering it.

 

12-12.5???????