Miss after 4 inch Maf pipe install

[dave34]

Installed my new 4 inch pipe and now I got a miss under boost. No other changes. Do I need to reprogram my gen 2 ? Is jumping from 3 in to 4 in changing readings/ calibrations ? I run a 3.5" Lt1 Maf sensor controlled by the gen 2 . Curious if any one else ran into this.

Turbotweak chip
Stock 109 with billet mains
Ported irons
Ported champion intake
Headers
Te61
206 roller cam
Atr ss exh.
Eastern front mount
55 lb siemans

 

[dave34]

Put 3 inch pipe back on ..runs fine. Both are solid pipes feeding into a 3 inch turbo inlet

 

[TurboBob]

you need to check the BLM's with the new pipe and compare with the old one.

B

 

[dave34]

you need to check the BLM's with the new pipe and compare with the old one.

B

Ok . Will do later and report back. Thanks

 

[dave34]

Idle( 825 rpm) blms engine warm - 4" pipe 132
3" pipe. 136

I looked closer and found I only have 1/8" or less between 3" up pipe and 4 " maf pipe and only 1/4" away from tensioner. I'm thinking under a good load..gear shift. Etc. It's hitting ..I see a little mark so I moved it a smidge and also put my engine torque strap back on ( I have hr poly motor mounts now ) . Ran it..hiccup gone for now. I still wonder if it's turbulent flow going from 3.5" sensor to 4" pipe to 3 " turbo that gets worse when pipe contacts other parts in the slightest . The pipe looks awesome like to keep it on.