OK guys, I'll fill ya in best I can and if you have more questions I would be glad to answer those too.

Vehicle: 2wd Yukon , 24 inch aftermarket wheels
Engine: 5.7L LS1 engine forged internals 8.7 to 1 comp ratio
Turbo kit: STS rear mount with FMIC (mechanical boost controler)

Tuning: Now this is where it gets interesting . Originally I tuned this vehicle by extending the MAF tables and using the PE vs RPM to fuel when under boost. The problem with this method is the simple fact that boost from a turbo can come in at different times depending on load , throttle position etc. I managed to make the same power level using PE vs RPM (well close, it made 472rw) . The problem with this was, at light throttle on the highway at times it would start to get into boost very quickly because of the shear mass of this thing. So now, we have a vehicle that is getting into boost at 25% throttle angle and no PE fueling to go along with it. If I added fuel in the main VE to compensate , the truck would become very slugish if not under boost . I tried bringing the throttle % down on the PE fueling, and once again it was very hit or miss as to whether or not the boost was going to coinside with throttle angle/boost level. On the dyno, all was well , but drivability suffered if I left things where I felt safe with the customer driving the truck "all out".

Fast forward a couple of days. Pete is in town (Plan B), and says to me "lets have a shot at it without the MAF and 02's" (Speed Density) . I say bring it on , and we start the long process. Needless to say, I learned about more SD tuning in a 3 day period from "the master" than I could have picked up in 6 months on my own. It's a different style of tuning for sure , and leaves nothing untuned for the MAF and 02's to "smooth over".

Results: The truck drives effortlessly , boost and fueling are "in sync" at all times , because now when the MAP reads boost it fuels directly from the main VE map. In short , HP tuners with a 2 bar MAP is the ONLY way to go on a force inducted vehicle. I HAVE SEEN THE LIGHT !!!

 

This is the kind of info I am looking for. Do you have any more info or know where I can find some more info on speed density? I want to set my truck up this way. I live in BFE and don't have much of a chose other than to learn 2 bar tuning myself. What MAP sender do I need to get to do this? I think I'm going to buy EFIlive for tune, because I believe it comes standard with 2 bar tuning. Any help would be apprieciated.

 

Tuning is way above my head, but that sounds really cool.

 

We use a MAP sensor from a 1987 Buick Grand National, but there are others available.

 

Good info.

 

look in the tuning section at the sticky there are links to ls1 and go to hp tuners all of what you need is on those two sites

 

there is alot of info over there, but its alot more difficult to get to the meat and potatoes. Id love to see a write up on this. Timing and WOT PE tuning is pretty straight forward, but I wouldnt know where to start. I wouldnt know where to start as far as disabling codes and even the process and adjustments and I havent found anything specific in the least for tuning a boosted vehicle even as simple as where to set WOT TPS to account for the part throttle boost.

 

Well, we are not going to give away all of our secrets

 

Started doing SD tuning this mournig. So far it looks like my tune is good in sd mode, so all i need to calibrate the MAF.

 

Guys , I agree with you there is a lot of theory based stuff out there on the net. I can babble on all day about how I do things with this program or that , but until you see it with your own eyes , it is still very hard to comprehend everything. On top of that , there is more than one way to skin a cat. Different tuners go about things in different ways , I just do what works best for me. If you guys have any specific questions regarding this subject, I'll answer them here or by PM , or feel free to give me a call 972 288 9500, ask for Sean.