Just got home from the dyno, very tired and been a long day so im gonna make this as short as possible.

Truck is a 2008 stock 4.8 truck. My truck is 4wd with factory 20's and bfg all terrains. The turbo is an on3 76mm. factory zr1 56lb injectors. I have it mid mounted under the truck.

here is what i was told, said i was running out of MAF (12k hertz) and that the turbo couldnt make more than 400 hp. (kinda doubtful on that) timing is set at 10 degrees, 10.9-11.0 a.f.r and he stopped at 9 psi. Waste gate is adjustable, can take it to 18-20. when im not so tired i will post my HPT tune file and the dyno sheet.

Anyways, i ended up with 375 hp / and i forget tq but it was close to it. He did mention he dynoed it in second gear for whatever reason. It was done on a mustang dyno. So what do you guys think? more on the table or do i need to start saving money?

 

At 9psi 10 degrees is not much timing. Not sure what you mean by 19.9-11.0 AFR, better not be seeing 19.9 AFR under any load.

 

If that turbo is in any area close to a good brand turbo of that size, then 400 hp is not a stretch at all. Like Pat said timing is def on the safe side, and the current afr could actually be leaned out some. HP will change dyno'n in 3rd gear though. Most people do it in third, maybe he was trying to get decent base lines on the tune.

 

I asked him to remove torque management also, but its still dead if I punch it from a dig. Truck seams really weak.

 

Its going to feel dead from a non-boosted dig. Its a 4.8. But it should not be out of MAF...something seems scaled wrong. The 08 MAF sensors can measure insane amounts of air.

 

Ya im pushin 12lbs and still runnin a maf, no prob here. Timing is also pretty conservative.

 

Keeping an eye on this. I'd be interested in seeing the tune.

 

Sounds like he's tuning conservatively, possibly scared of turning you loose then having you pulling a big trailer with it or something. Dyno shops seem to be like that unless they know the car and customer very well...

 

Something is wrong with those numbers for sure. I was running 10psi on a master power 76mm turbo on my 4.8 AFR was 10.0-10.2 timing at only 8* and it was still moving out good. Ran 114mph in the 1/4 mile and with a bad trans

 

Im not driving the truck today or i would pull the file. He is supposed to email me the graph and file this morning. Kinda sucks its so sluggish from a dig. even with TM supposedly turned off. Oh well, i should have the graph/ tune up in a little bit.