GM says that in the LLY at 1600 rpm 590 lb-ft of torque is acheived in 2nd, 3rd and 4th gears and 520 lb-ft in 1st and 5th gear. Has anyone with a free flowing exhaust on their LLY noticed this change resulting from a different power curve?

The programming for the LLY restricts the output in 1st and 5th to preserve the Ally, since no upgrades were done to it for the LLY engine's increased output levels.


I guess I don't understand your question about the free flowing exhaust...http://www.dieselplace.com/forum/smileys/Confused.gif

Sorry should have said more ... Sometimes a reduction in backpressure in an engine will cause the engines power and torque cures to change. As in the case of a truck gas engine with a fair amount of back pressure where the power comes in low rpm and a race car with almost no Backpressure where the power comes in at high rpm