see this quote from the edmonds write up... for a 6l vortec max


http://www.edmunds.com/insideline/do.../pageId=118457


"""""As it turns out, the explanation boils down to an engine calibration strategy. GM calibrated the 367-hp 6.0-liter V8 to remain in stoichiometric "closed-loop" fuel delivery mode for 4 seconds after the throttle is floored. This fueling strategy helps keep emissions in check (and saves fuel) at the expense of reduced power — about 40 hp less at the peak. Once the driver lifts his right foot from the wide-open throttle position, the 4-second clock resets.

This explains why the Silverado's power is low everywhere on the graph right up to the jump in power right before redline. Corresponding to the expiration of the 4-second window, the jump in power is indicative of the engine switching to open-loop "power enrichment" mode. It is only when operating in this mode that the engine delivers its full rated power.""""


If you look at the dyno charts the chevy is a dog thru the curve and spikes at 5k rpm to reach the claimed HP.

My first question is will a Diablo tuner be able to tune this out, I know it has some tuning functions beyond a canned tune, but am not sure if it would address this issue.

Second ?, would this OE calibration affect normal daily driving or just wot, ie will it have a good flat curve except when wot.

Third, answer probably yes, will a Nelson tune be able to address this issue.

I ask because I have a new rig on order and want to have what I need by the time the truck arrives.
If the truck can be tuned for this it should be a runner
Thanx, Dave

 

no takers?

 

you may want to talk to the guys at nelson and diablo motorsports directly. i have an 07 on order as well but, i dont think they changed the computer much for the 4.8.

 

I have been curious also. I have an 07 and I am sure there is alot to be done with tuning. It feels like it is being held back a bit. I don't know what is out there for tuning yet, other than Hptuners and probably EFI live. Nelson has tuned them also. I'm debating trying to tune myself or going with Nelson

 

im gonna bite the bullet and go ahead with the hp tuners. whats the worst thing that could happen........blow a motor thats what a 5yr, 100,000 is for

 

anyone got a stock tune for it they could post here?

 

I'm leaning towards the Hptuners also. I'm a bit nervous to make changes but at least I can undo any of the changes! That PE delay mentioned in the article above has got to go.

 

not now but will in a week. why???

 

i figure if GM thinks these engines can run that lean at WOT at least for a while, i think i could use it to make some extra initial power by running it extra lean at least for a moment, give is some extra torque right off the bat--right?

 

im pretty sure we have a few 07 full size SUV files in the repository marcin...if you don't have access let me know & I'll grab one & post it here if need be.