COS 3 Lean issues under boost

[blazinblue]

Having some lean issues under boost in first gear it starts out around 10.5 afr and it leans out to about 14.5, going around 40mph it does lean out abit to about 12.7afr as you can see in the log.


i have do the AutoVe its not that close but its getting there

tune and log



mods are:
76mm Turbo
6.0 lq4
72lb injectrors
7psi boost
walbro 255 intank

[odd boy]

post dyno sheet please.

[odd boy]

If u didn't have it on dyno, you need to consider the following for causing lean:

1. Weak fuel pump (install pressure gauge and observe it)
2. Wrong tuning, I will check your file later.
3. Bends in the fuel system.
4. Wrong installation of the fuel system, in case of using big fuel pumps with new fuel line.
5. Small injectors (not applicable for your setup)
6. Bad MAF sensor incase it is maf tuned.

[odd boy]

Please fill the below table

RPM MAP AFR
2000
2500
3000
3500
4000
4500
5000
6000

[blazinblue]

i attached the log in the first post. It shows the afr

[johnv]

For starters you have too much timing under boost, I see 7 deg knock retard in the log,
You need to use the boost timing table to pull timing !!

Your commanding 10.5 AFR in PE , too rich unless your on E85
aim for 11.5-11.8 AFR

Your boost VE table has big numbers in the areas your going lean , so i suspect your running out of fuel pump, check fuel pressure under boost.

Going by your Injector flow rate table you have a boost ref feul regulator (flat instead of sloped table) is that correct ?