The primary reason I switched to speed density was because Dewy was doing it....and I do eveything (and everyone) Dewy does.

Besides that, i do like being able to adjust the fuel for each pound of boost rather than just throwing a bunch of fuel at the 105kPa column. I did like the precision that the MAF had, but the SD tune just feels much more responsive, especially after i got the VE table dialed in closer. There may be other ways to get the fueling done besides a SD tune, but i am not extremely versed in tuning and Justin has not showed up at the house yet to give me lessons......even though he only lives an hour away now.

 

I wouldn't recomend going with a bigger maf until your tuner can get your stocker to run right. If you get the stocker to work, then upgrade. That's like putting slicks on a 14 second truck to fix a traction problem. Most of the faster trucks I've worked with max the maf on a regular basis and don't have this kind of problem. For that matter, Chase used to max his maf from a couple seconds into a pass and all the way through the quarter until he let off. His didn't have that problem either that I recall.

 

If it is in the tune like you say wouldn't it just idle bad all the time.

 

Once the code is tripped, the MAF is ignored until you shut the truck off and restart it. Your idle shouldn't be that bad though unless your tune is in open loop and the VE table is significantly out of whack.

 

Whether you have some kind of air leak pre or post throttle body might be in question too, but I wouldn't go changing any maf until you find out what is actually causing your current problem.

 

i am not really looking to change anything. I was just looking for the most logical answer to the problem. The problem started with the pulley change so it is most likely in the tune. I am new to this so i was just curious if you guy's had any issues as you increaced boost.

 

not to high jack the thread but can someone refer to https://www.performancetrucks.net/fo...d.php?t=412330 and explain to me what needs to be done to tune the maf for boost......thanks.

 

Think I found the problem. Vacuum leak. All the intake bolts were loose tightened them up and idle is much better. I figure it might take a while for it to learn out the air issues. Looks promising though. I am wondering if it had a vac leak during the last tune will it affect anything now that it is corrected or will the computer take care of that.

 

you had it dyno tuned with an intake leak? yes, retune! yes the PCM will correct part throttle if you are closed loop. What's your typical boost #'s?

 

I am getting ready to buy some nexxus guages this week but they told me during the tune it was at 8.5. Maybe it is actually higher without the vac leak.