Ok maybe i should have explained. James @ RWTD did my tunes. Car made the 449 with the stock cat pipe and 23 degrees of timing with the regular pulley tune. He then sent me 2 other tunes to try with my new H pipe. Identical A/Fs. He called one of them "agressive" which had 22 degrees. The other file had 21 degrees. Both of the 21 and 22 degree tunes put down identical #s, and both backed it up with another pul that made 1-2hp less.
So to sum it up, there was actually timing pulled out of the tune with the new H pipe. The gain was from the swap for sure and not the tuning. A/Fs were identical.
Dave
So to sum it up, there was actually timing pulled out of the tune with the new H pipe. The gain was from the swap for sure and not the tuning. A/Fs were identical.
Dave