I am having lean problem.

I am having 12.5 AFR under load but it goes back up to 13/14
WOT.

HKS tech support said teh pump I installed with the kit does 80-LPH.

Could I simpley upgrage to 190 or 255 pump?

Is there any negative effect?

Does it has to be turned? My F-con is not turnable.

 

Could you give us somemore info? At the top of the RPM range it goes to 13/14 AFR? The pump in the kit is more then enough. What is your boost like? Is it holding all the way to redline?

 

I don't ahve a boost meter, only AFR & Transmission T.
AFR start at 12.9
Idle at 14.5
Drive at 14.5 unless accelaration, 3000-5500 range at load,
AFR drops to 12.9-12.2
Any time I do WOT: AFR goes back up to 13 /14 range
(HKS adviced me not to WOT until fix it, Danger!)

Did a 1/4 mile run at WOT, the AFR is 13-14 the whole time during WOT
WOT AFR is 13 to 14 regardless what rpm or at any gear.

HKS said their pump is 80 lph, so I ordered 255 LPH pump. Hope the bigger pump will fix the problem.

What do you experts think?

What's happening at WOT? Why is it 12.2 at load 5500 rpm but
WOT jumps to 13, 14?

 

Something isnt working right . You dont need to add anything , just fix what you have !!!

 

 

I believe the stock pump does 90 LPH and the one supplied in the kit does about 165 LPH

 

The fuel pump MAY fix the issue but at the same time will cause you to idle and cruise too rich. So the pump should not be replaced. Check that your HKS map sensor is connected and that the vaccuum line is connected with no leaks. If that is not the issue then make sure you are building boost all the way to redline. The belt may be slipping. Also how old is your AF sensor?

 

Just an update.


My installer have just installed the 255 fuel pump. Also found a connector to
the two additional 525cc HKS "in plenum" injector is loose.

I'll get my car back today, hope this problem is solved.

 

That will fix the problem. IIRC they are 1000cc Injectors.

 

Just got my car back.

It seems to have fixed the problem. I see 11 in the AFR now whcih I
never saw before.

 

cool, glad everything is better now.

 

Sweet !!