This is a friends truck who had his truck built and tuned by a local shop. He brought it to us because it started making a knocking noise in the engine that turned out to be a rocker arm coming loose. During our inspection we found a slew of issues that we have since fixed (boost leaks, vacuum leak at fpr, questionable map sensor, fuel pump wiring, loose suspension, the list goes on). Once we fixed all of the issues, he asked us to look over his tune and to take a look at the logs and see if we see anything out of wack because the truck runs just awful. We installed an AEM Wideband and have it logging through the EGR.
Truck Specs: P59, 6.0, 88mm T6, Bosch 210lb injectors, E85, big cam, 4L80, 3200 stall. His exhaust manifold setup goes around the back of the engine and collects into the bank 2 header, and then out the front of the bank 2 header into a collector for the turbo. Seems like a bad way to do it imo, but maybe it works, idunno, were not really LS guys so HP Tuners is something were pretty new to, especially tuning turbo cars on speed density.
Tune File attached below. Supposedly made 800+whp like this.
BobbyTune plus EGR enabled for AFR.hpt
Upon initial start up, it seems to idle ok. It will idle cold around stoich, then slowly start to richen up.
When trying to accelerate from a stop, it instantly goes lean with light throttle, and does not want to accelerate unless you give it half throttle or so. Then it finally wakes up and starts to move. During this time, the map sensor seems to read way off. With the key off, it reads 98kpa, but with a load it barely gets over 50-60kpa and it feels like it should be around 100kpa. I notice the map sensor linear and offset are wacky and do not correlate to a GM 3bar sensor but maybe a 4bar map sensor? The map sensor he has installed is part# 12623671. However when I try to use the 3bar data, the kpa with engine off goes to 70ish or even 50ish with different settings.
Under WOT it takes FOREVER to build boost, but it does run in the lows 11s high 10s for AFR.
Throttle never fully hits 100%. APP shows around 70ish and TPS shows around 70ish. He did say that his pedal wont go all the way to the ground bc of dynomat material under it. Can we adjust this? Or should we just cut that material out?
Look at this VE Map... Like I said, i dont tune much on HP Tuners, tinker here and there, but in any VE map ive ever messed with on standalones ive never had values this low. I can only assume its due to a miscalculation in injector data for the Bosch 210s? Or is this normal?
PE also seems to be useless, is this a Speed Density thing? Does it not use PE at all in this mode?
Last thing, he says it goes into reduced power mode if he uses the column shifter to downshift and hold a gear rather then just using D.
At this point, we may just contract someone out to remote in and tune it for us. Truck is really cool and has a lot of potential, and we just want to help him get it right! Thanks guys
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Originally Posted by chopperrudy
