how is the best way to tell if you have gears in your car already and also my car has 245 45 17's will 275 40 17 drag tires fit and lastly i was thinking of doing the PI swap but somone told me my pistions wont last due to the milage about 90,000 to 100,000 not sure because the clutch was changed before i got it and now odmeter dose not work and advice on any subject would be greatly apreciated

 

1. you can count the teeth on the gears them selves, tell us the mph at in a certiune gear going a certine speed.

2.270/40/17 can fit on 17x8 wheels which i am asuming you have so yes.

3. you can do the swap that wont make the pistons die.

 

i was trying to find the gear ratio with out tearing the rear end apart and it wont tear anything to do the head swap?

 

Go drive around and give us your MPH and your RPMs at a certain speed in X gear. Report back.

 

or jack up the back of your car, put a piece of tape on your driveshaft, spin your rear tire exactly one rev and count how many times your driveshaft spins, that's what gears you have, example, 3 3/4 times, you have 3:73's 4 and a little 4:10's, etc..

 

nice thanks guys ill try that

 

not exactly the most accutet way.

easyer way go and drive the car at 40mph in 4th gear tell us the Rpms and i will tell you the gears you have.

 

headswap is fine even for high mileage. Your bottom end will thank you for a freshening though. Stay with Hypereutectic pistons and stock-ish rods and it won't cost that much. Make sure to have the block gone through and honed where needed.

275/45/17 is not ideal for a 17x8 but it's ok. You won't get the sidewall strength you'd have if you mounted them on 17x9 (the correct wheel size for 275's) but it might help your times since the sidewalls will flex instead of letting the tires spin quite as easily.

Your 96GT came with 3.27's IIRC. The tape on the driveshaft method is the most accurate way you can go without making any assumptions about the accuracy of your non-functional instrument array. Since your odo doesn't work, I'll assume your speedo doesn't either. Use the tape method and you'll be fine.

 

wow thank so much guys that is alot of great info i get back with my findings as soon as i get a chance

 

alright guys in 4th gear @40mph i am at about 2100 rpm

 

That looks like 4.10's to me. If so, then stick with those. I have 4.10's as well and that's what my RPM's about sit at with those settings.