Hey guys i'm having some fueling issues with the car right now. Even with the cells set at 7.4 i cant get my a/f to drop below 12 from 3k-5k rpms. above 5k the a/f is pretty normal even without the cells maxed. I have the timing reduced so i dont get much knock if any, but its worrisome. I would attach a log, but I'm not sure where to host it. any suggestion is helpful.

Mod list:
invidia 3" catback
tanabe 2.75" downpipe
Invidia o2 housing
ebay test pipe
dejon tool mbc
cosworth 272 cams
denso 720 injectors (yes they're scaled properly)
Walbro fuel pump
ams replica fmic
speed source licp
k&n drop in filter
aps bov
JDM Map sensor

 

Lean spool enabled?...even though that still sounds a bit extreme for that to be the problem. This sometimes might also be a problem with the fuel pump, but after 5k your saying the AFRs are normal?

 

Lean spool is enabled. Yeah the curve is wierd it peaks at 12.3:1 3.5k then tapers down to 11.5:1 at 5k and 11:1 at 5.5k to redline. Seems like it would be flowing more fuel at higher rpm so if it was the pump it would be having problems there right?

 

lean spool. 5k part is a little odd though.

 

I had a ton of maxed cells in that range and it all went away once I disabled LeanSpool. Its not the pump and your AFR curve is exactly where I think it should be. Just try disabling LeanSpool and see how the results are.

What is your max injector duty cycle?

 

Disabling lean spool now and going to try it out. My injector duty cycle maxes at ~75% at 7k rpm.

 

Psh, if they are stock injectors....its DEFINITELY not the pump.

 

They're denso 720s

 

720cc stated in first post.

It's lean spool, saw it many a times on the dyno when the IX's first came out and started getting modded with more airflow and boost.

 

I'm going right now to flash it and test it out.

 

Damn. Its 4am here, yes I'm pulling that card,lol. Well, 75% on 720's is equal to 96% on stock 560's so the pump is completely fine, it'll be the LeanSpool. Good luck and keep us updated.

 

Yep just did a couple logs and the a/f is way lower now. 11.2 @ 3.5k vs 12.3 @ 3.5k before. Now its just a matter of retuning the fuel map. Thanks a lot guys I cant tell you how much I appreciate it!

 

Glad to hear it

 

Yeah I wanted to make sure that was correct...they had been one or two odd cases where the pump was behaving oddly (a good bit of the time because the correct walbro install kit was'nt ordered) but it would obviously be worse at high rpm . Anyway lean spool it was.