E.A.
July 15th, 2008, 03:16 AM
** Sorry I posted in the wrong section last time **
This is on a 2007 TBSS AWD.
Stock the truck dyno'ed 275awhp
After L92 heads, intake and cam dyno'ed 402awhp
Now I have made a custom bracket to hold a ProCharger D1SC on the passengers side cyl head. She makes right at 6psi of boost before a shift.
This combo is identical (even the boost level) to what i put on LS2 6.0L GTO's (E40) and make 650rwhp
This TBSS is running in 2bar SD mode, thanks to the EFI Live Virtual VE.
Now the odd isses:
1.) Can't get throttle to go past 39% unless truck is moving.
**update** I have this resolved, though I only changed one thing, that shouldn't have fix it, it did for whatever reason
- So basically, if your trying to race someone from a stoplight forget about it, because it will just launch from basically idle (29% throttle is parked). So it won't even get the truck up into the stall converter. Once you let off the brakes, and you get about 2 mph to show on the data log. INSTANT jump to 83% throttle, and the truck takes off. (quite strong for its weight) Where am I not finding the table to be able to take this feature off? I understand that its there to save the tranny, but in this trucks case it doesn't need to be saved. It will only do this randomly, with no real reasoning behind it. Yet if you are in Reverse, it will go WOT, everytime no matter if you have movement or not.
2.) The most rapid fluttering of timing I have ever seen in my tuning days.
- As power comes up from 1700-3600rpm the timing looks normal, and is following the curve that I command. Then out of the blue the timing will rapidly jump from 3 degrees to 10 degrees multiple times a second.....only to get worse as RPM goes up. So at redline the jump is from -3 degrees to 8 degrees. (the timing graph on the data log looks like a sign wave almost) **UPDATE** I have now logged the TQ values and retard due to TQ Managment. The issues start happening right at 500lbs of TQ, then once it gets to 640ft lbs of TQ it starts pulling 6 degrees off and on, with PID SEMRET (Retard due to TQ Managment) Which is where it was getting the worse. Once it pulls all the timing (13 degrees) the TQ amount drops below 500ft lbs, and it brings the timing back in, just to pull it all right back out again. Thus the rapid up and down swinging I was seeing the other night in logs, and well feeling in my seat of the pants driving.
3.) When "punching" the throttle to go WOT it drops to -6.5 degrees
- Anytime you mat the gas (once your rolling) it will drop the timing to -6.5 degrees, then ramp it back in. I assume this is also to save the tranny on a downshift, but all of the TQ management has been turned off. The best way to describe the feeling is like having a car with a big stall, then locking the TQ converter. (Yet this happens in gears that don't have the TQ locked at all)
Don't get me wrong, it runs really strong. But these small little issues have me scratching my head. If I could WOT it from a stop, and keep the timing in her though the full RPM band.... it would really scream for a SUV.
** July 15th Update ***
I took the final SD tune, and went back to a MAF tune. Same timing, same A/F ratios under drive and WOT. All issues are now resolved. For whatever reason, when it was in SD mode it did NOT like making that much TQ.
I am happy that the issues are gone. But not really because I want to fully understand what was causing the issues. It seems that in SD mode, the magic 640 ft lbs of TQ wasn't going to be bypassed. Yet now just by turning the MAF back on its fine with it. ?!?!?! Seems odd to me.
Any pointers in the correct direction will be greatly appreciated.
Thanks so much,
Erik
This is on a 2007 TBSS AWD.
Stock the truck dyno'ed 275awhp
After L92 heads, intake and cam dyno'ed 402awhp
Now I have made a custom bracket to hold a ProCharger D1SC on the passengers side cyl head. She makes right at 6psi of boost before a shift.
This combo is identical (even the boost level) to what i put on LS2 6.0L GTO's (E40) and make 650rwhp
This TBSS is running in 2bar SD mode, thanks to the EFI Live Virtual VE.
Now the odd isses:
1.) Can't get throttle to go past 39% unless truck is moving.
**update** I have this resolved, though I only changed one thing, that shouldn't have fix it, it did for whatever reason
- So basically, if your trying to race someone from a stoplight forget about it, because it will just launch from basically idle (29% throttle is parked). So it won't even get the truck up into the stall converter. Once you let off the brakes, and you get about 2 mph to show on the data log. INSTANT jump to 83% throttle, and the truck takes off. (quite strong for its weight) Where am I not finding the table to be able to take this feature off? I understand that its there to save the tranny, but in this trucks case it doesn't need to be saved. It will only do this randomly, with no real reasoning behind it. Yet if you are in Reverse, it will go WOT, everytime no matter if you have movement or not.
2.) The most rapid fluttering of timing I have ever seen in my tuning days.
- As power comes up from 1700-3600rpm the timing looks normal, and is following the curve that I command. Then out of the blue the timing will rapidly jump from 3 degrees to 10 degrees multiple times a second.....only to get worse as RPM goes up. So at redline the jump is from -3 degrees to 8 degrees. (the timing graph on the data log looks like a sign wave almost) **UPDATE** I have now logged the TQ values and retard due to TQ Managment. The issues start happening right at 500lbs of TQ, then once it gets to 640ft lbs of TQ it starts pulling 6 degrees off and on, with PID SEMRET (Retard due to TQ Managment) Which is where it was getting the worse. Once it pulls all the timing (13 degrees) the TQ amount drops below 500ft lbs, and it brings the timing back in, just to pull it all right back out again. Thus the rapid up and down swinging I was seeing the other night in logs, and well feeling in my seat of the pants driving.
3.) When "punching" the throttle to go WOT it drops to -6.5 degrees
- Anytime you mat the gas (once your rolling) it will drop the timing to -6.5 degrees, then ramp it back in. I assume this is also to save the tranny on a downshift, but all of the TQ management has been turned off. The best way to describe the feeling is like having a car with a big stall, then locking the TQ converter. (Yet this happens in gears that don't have the TQ locked at all)
Don't get me wrong, it runs really strong. But these small little issues have me scratching my head. If I could WOT it from a stop, and keep the timing in her though the full RPM band.... it would really scream for a SUV.
** July 15th Update ***
I took the final SD tune, and went back to a MAF tune. Same timing, same A/F ratios under drive and WOT. All issues are now resolved. For whatever reason, when it was in SD mode it did NOT like making that much TQ.
I am happy that the issues are gone. But not really because I want to fully understand what was causing the issues. It seems that in SD mode, the magic 640 ft lbs of TQ wasn't going to be bypassed. Yet now just by turning the MAF back on its fine with it. ?!?!?! Seems odd to me.
Any pointers in the correct direction will be greatly appreciated.
Thanks so much,
Erik