The comments here from hahnmgh63 and choppo are good. I would suggest H-Sport sway bars to help with the understeer and excess body roll in the twisties. If you want to have an intelligent conversation about exhaust systems, trannies and chips, contact Bob at Stratmosphere. See link below. Keep in mind that this is one vendor that's in the business of selling this type of hardware. But they know what they're talking about IMO.

• Stratmosphere Link