Does tire height affect tune?
i think i might be tuning the incorrect cells due to tire size. when i logged fuel trim cell, it would be off from what the rpm/map ve cell i thought it should have been correlated with.
same with the spark, the cell that i thought i should be tuning would not have the the advance showing on the scan.
last night i went to the track and had 215/40/18 fronts and 255/40/18 backs and changed the tire size to that of the backs and my shifts felt weaker and and the last gear wasn't feeling right. my trap was 102 mph vs when i had the 20's on the back it would trap 105mph.
could be a trans issue or something else but i'm leaning towards the tire size changing the tune.
BTW - I know most TB SS owners prefer buying canned tunes, but buying a locked tune is not the way to go. I tuned my own and picked up 17awhp across the board and 23 hp in some parts. And that was with 8 degrees of false knock at WOT. Torque was up even more.


