I have been helping a local with tuning and been having a problem with the car going lean up top regardless of richening the map.

2003 Evo 8
Mods:
Walbro (6 months old)
QTP downpipe - cutout open
EPM O2 dump
Ported Exhaust mani
ETS Full intake
Evo 9 turbo
ETS short route IC piping
Mil.spec TB seals

Stock injectors

Below is a pull with the IPQ and IDC. It looks like the IDC is peaking way over 100% (i am not sure how accurate evoscan is). I have never had an 8 or 9 turbo over run the injectors. I also suspected the ETS intake but I am not sure, I have never experienced this before. Car is making a good amount of power which is why i think injectors.

I couldn't log AFRs due to an issue with the Uego. It is fine until 5500/6krpm then it creeps into the mid 12s by redline.
Thoughts?



Thanks in advance

-Mike

 

Has the fuel filter in tank been replaced?

 

I haven't asked but i would have assumed when the pump was replaced the sock was also replaced.

 

Yes, and the pump is about a year and a half old.

 

Not talking about the sock, I mean the actual filter. The white plastic assembly the pump clips into. The other thing with the stock turbo dumps (dont ask me why the normal externals are fine) is that they almost always read "off".

 

my evo injectors max out at bout 26-27psi or 260load... so honestly sounds pretty accurate to me.... no that i have much evo experience but its what i saw when my boost crept from 20 to 27 psi... also if your running over the 100% will lean things out maybe thats why your hitting 12s in higher rpm unless you have that in you map....

 

you mean the AFRs read off?

We might have to pull the pump assembly and check the other filter.

 

think he mean they dont follow maped afrs as they should.

 

I rarely have tuned an evo where they are close.

 

maped figuratively speaking.. i ment to say desired

 

I can't tell what mass airflow that car is flowing, but the stock injectors when maxed out on a stock turbo should (under ideal circumstances) lean out to around 12:1 AFR.

So, if the turbo truly is maxed out, then your 12:1 at the top end may be accurate.

 

Yeah it will say its leaner than it actually is. The only way I figured it out beyond the shadow of a doubt was to move the WB to the primary O2 spot in the O2 housing.

Mapped AFRs never match on stock injectors and only sometimes on larger injectors. Alot of that depends on your patience and how willing you are to fiddle with them. I get them close to real life usually but never worry about being exact.

I havent ever seen a stock turbo max out the injectors at 27psi either, not saying it cant but I havent seen it personally out of all the ones we have done. Usually that seems to be 28-29psi or so on the spike and then at peak power its down to 23 or so. The extra 2psi at 6250 or so can be enough to eat up the remaining fuel.

 

I agree with you, and said the same thing last night. I have never seen stock injectors max out on any stock turbo.

I am not getting knock. Unfortunately i can't monitor EGTs which would help see if the leanness was real. It didn't matter how much fuel i removed the WB number didnt change.

I think it is a good idea to check the filter and go from there.

Thanks for the input all.

 

I havent ever seen knock when lean. That includes FPR lines blowing off mid pull.

 

i would agree, the other day comming back home, had my FPR line came off and the car felt very strange.... power then no power then a little power and then no power..... and slight knock 1-3.

checked the logs and the WB02 was pegged at 16.88.... max its supposed to show... i wonder what i was running really