Going for broke

I run a used car lot and have an 06 gt coupe with 21k miles on my lot. It's bone stock with an auto and 3.31 gears. I personally own an 08 gt vert with an auto and of course the 3.31 rear gears. I am running a c&l cai with a 93 octane brenspeed tune. My question is this, Although both cars possess the same rubber to my knowledge(bf goodrich oem tires) the stock 06 will literally anniliate the tires from a go whereas my vert will spin maybe 3-5 feet and then go. the 06 feels snappier from the hit but not so much from a kickdown. Of course with the canned tune on my 08 the shifts are much firmer. I guess I'm not sure if the difference off the line might be due to weight of the coupe vs. the vert, the miles of the coupe (21k) vs. the vert (6k) or from the 93 octane tune pulling timing initially?? I thought of going to the 87 octane tune to try but just wondered if anyone else has had a similar experience between multiple cars owned or buddies with mustangs seeming to posess different qualities.

8178A

Not unusual. My O9 GT manual is setup exactly the same as my 07 and the 09 feels noticeably faster.

Going for broke

yea it's strange.. I wonder if the tires are the culprit from being two years older on the 06?? I drove them both again last night back to back and the results were the same.. the 06 just blows the tires off and the 08 will spin a few feet and then just hooks. I'm going to try the 91 octane tune from brenspeed I have and then see if that improves the snapiness off the lineon the 08.

Black GT

How much tread wear is there? I don't think the same tires being two years older would make that much difference.

If you had time you could swap wheels on each and try it again, that would tell you if it was a tire issue.

jmk3

05 06 S197's were lighter, + your vert is heavier.