I don't think there is a clutch that is strong enough in a 4 or 5 speed which fits the 617 and I'm not willing to start modifying those- although I'd love a stick instead of the auto. I don't really care for higher top speed or better fuel mileage so a lower differential is not appealing. It's hard to spin the wheels as is so a LSD is not needed. Next is more air options but I don't want to change the exhaust then buy a new turbo which needs a new exhaust/downpipe. Seems like I should do those together. Got ideas about a cheap 3 inch exhaust? My downpipe as it sits now needs work. I don't want the "drone" which comes from straight pipe so I'm wondering what I should do about increasing the diameter and keeping the front muffler.