I was going to get an '05 GTO, but decided to hold out for an '06 with the T56 6-speed. I wanted to change the rear gearing to something in the arena of 4.10. I am also debating between a custom tuned supercharger or a twin turbo setup. I would like to know about what can the chassis and driveline take? Will the T56 hold up? I have the option of an IFS Ford :pain: 9-inch rear end with billet halfshafts. Will the stock rear end hold up to this or am I going to have to upgrade it? How high can I go with tires, and not have rubbing problems? Any info would be greatly appreciated.

I dont know about drive line but I know that if your going to have anything over 4 lbs of boost I would highly recommend rebuilding the bottom half of the engine. As far as tires go, 275 on the back and nothing over 245 on the front. Make sure that if you change brand of tires from stock on the front that the tires dont rub on the shock even if it is still 245.

Iv had 4:10s ina T56 Camaro, you may not want to go that rout, as it cripples your top end, and makes daily driving a hassle, (shifting to 2nd before you get across a street light) I think 3:73s may be the best gear overall.

As for the rear end, I havn't herd of anyone replacing it, but have herd the halfshafts will go...but only towards the higher powers...you should ask Howie, he has a couple FI'ed GTOS, or some of the other tuners.

Originally posted by torridredaccd@Jul 17 2005, 03:06 AM
I dont know about drive line but I know that if your going to have anything over 4 lbs of boost I would highly recommend rebuilding the bottom half of the engine.
Naw.....

The STS pushes 5psi safe and the ATI is 7-9 safe. But yes only low boost with the stock lowend