[335devin]

The car always seems to be 2-3 psi below target.

Stage 2 pull
https://datazap.me/u/devin/2014-335i...&mark=85-61-59

[thejeremyman9]

You need to enable throttle position and WGDC (and probably some other paramters) in your logs but looks like it could be a boost leak. You didnt list mod or recent maint. or anything; have you smoke/pressure tested? Are you 8AT? If so you should log 4th

[335devin]

Ok I turned on the settings you said and did it in 4th. The boost seems better on this pull I also noticed I only get a -0.1 psi vacuum on idle shouldn’t it be a lot higher. And would a vacuum cause low boost?

https://datazap.me/u/devin/stage-2-pull?log=0&data=4-20

[thejeremyman9]

Not necessarily RE vacuum. Are you asking if vaccum leak causes low boost? depending if its pre- or post-turbo leak.

In the new log WGDC looks reasonable and you are within ~1psi so if there is a leak its probably not a big one.

I havent ran the 2+ 91 map in a long time but here's a log of 2+ E20. https://datazap.me/u/thejeremyman9/2...&data=4-5-7-22

i am closer to target but i did everything i could with aftermarket orings etc and have pressure tested

[5soko]

I talked to MHD about PWG cars not hitting exact boost targets, and it seems to be a common and a normal occurrence, that the variance of a few psi is acceptable, esp up top where the PWG turbos cant flow well.

[thejeremyman9]

Originally Posted by 5soko

I talked to MHD about PWG cars not hitting exact boost targets, and it seems to be a common and a normal occurrence, that the variance of a few psi is acceptable, esp up top where the PWG turbos cant flow well.

Isnt OP EWG?

PWG also runs a lower boost target at higher RPM, though. Boost control isnt as precise as EWG for sure so I wouldnt necessarily go chasing a boost leak for small deviations, but a few psi is quite a bit of power.

[335devin]

https://datazap.me/u/devin/335i-stag...44&zoom=12-105

• Yea my cars 2014 335i so EWG. I have done a couple mods since that being a catless downpipe and a cat back exhaust and the boost problem is basically gone. I think it was my old exhaust which had a massive bend close to the downpipe which was definitely causing some rescriction. The problem I’m having now is lots of timing being pulled which I think is because the car is on the stock plugs and it’s getting hotter now. Should I go a step colder or would timing get pulled no matter what cause of it being 85+ plus outside?

[thejeremyman9]

Originally Posted by 335devin

https://datazap.me/u/devin/335i-stag...44&zoom=12-105

• Yea my cars 2014 335i so EWG. I have done a couple mods since that being a catless downpipe and a cat back exhaust and the boost problem is basically gone. I think it was my old exhaust which had a massive bend close to the downpipe which was definitely causing some rescriction. The problem I’m having now is lots of timing being pulled which I think is because the car is on the stock plugs and it’s getting hotter now. Should I go a step colder or would timing get pulled no matter what cause of it being 85+ plus outside?

You dont need colder plugs. If your plugs are old you can try fresh stock plugs stock gap. However if you are in Cali its probably fuel quality. I experienced the same thing and could never get consistently good timing on the 91 map. I went E30 fuel (on stage 2+ E20 map) and never looked back... have been running that for years.

Check the pearson fuels app/website to find E85 near you

[335devin]

Originally Posted by thejeremyman9

You dont need colder plugs. If your plugs are old you can try fresh stock plugs stock gap. However if you are in Cali its probably fuel quality. I experienced the same thing and could never get consistently good timing on the 91 map. I went E30 fuel (on stage 2+ E20 map) and never looked back... have been running that for years.

Check the pearson fuels app/website to find E85 near you

Ok yea I’m in Cali stock plugs were just changed probably have 1000miles on them. I wasn’t having any timing pulled in the winter
Isn’t -8 degrees pretty bad and would that mean I’m getting knock or what? I have ran e85 before not a fan of getting gas every 2-3 days tho cause this is my daily.

[thejeremyman9]

Originally Posted by 335devin

Ok yea I’m in Cali stock plugs were just changed probably have 1000miles on them. I wasn’t having any timing pulled in the winter
Isn’t -8 degrees pretty bad and would that mean I’m getting knock or what? I have ran e85 before not a fan of getting gas every 2-3 days tho cause this is my daily.

-8 deg is a lot of correction yes. Running E30 is only going to slightly decrease your fuel economy... pump gas is already E10. If you have MHD you could also run the full E85 maps on stock fuel system but then you would have about ~30% less fuel economy.