Grand Am GT at Mid-Michigan Motorplex

A nice fall afternoon at Mid-Michigan Motorplex. 99 Grand Am GT vs a nice RX7
My Grand Am mods are WAI, cat delete, SLP Loud-Mouth exhuast, and DHP PCM

Category:

Autos & Vehicles

Tags:

• Grand
• Am
• GT
• Drag
• Race

[highoutputdriver]

Actually I had better peformance without the cat, I was able to tune it so I had the extra fuel for the lack of back pressure. I have a high flow on now becuase with the headers, its just way too damn loud without a cat.

[devon63136]

How much improvement did you see after the headers??

[highoutputdriver]

Quite a bit, lots of top end gain and good torque increase too. The car has ran a best of 15.14 @ 91.8mph with the headers and with 18's on it. But the transmission is slipping bad, the log of the run said the 1-2 shift now takes almost a full second to shift instead of less then a half a tenth of a second to shift.

I only could only imagine what it would have run with a good 1-2 shfit and better than a 2.3 60ft time.....

[themanytoys15]

in my opinion but back the cat, or put a high perfromance one. TRust me on this one, i took off mine and it ran like shit, i put it back on and ran amazing again.

[kashrx7]

Thats a pretty quick RX7