I just finished the mod's on my 85 GT. I want to dump the 7.5 rear end for an 8.8 and am undecided on how strong I should build it. Without dyno testing the motor I'm guessing I have around 300 RWHP. The car also has the factory T5 trans. If I go with the 28 spline axle's I will save about $300 as I would still be able to use my stock one's. I've been told by a couple of seasoned racers that the 31 spline would be over-kill and to save the $300 to spend on something else. They say I just don't have the HP to justify the 31 spline. Also, because of the highway miles I drive would I be smarter to go with 3.55 gears or 3.73? Running the stock 2.73 now and spin the tires pretty easy

 

GO 31 SPLINES ,,28 ARE WEAK EVEN FOR A STOCK STANG..SAVING $300.00 ISNT WORTH YOUR LIFE,, IF YOU BREAK AN AXLE???

 

MAN has a point and you can not run the c-clips anywayz, go with teh 31 spline.

 

i still got c clips in mine but 31 splines is alot stronger...i didnt know at the time i was going to break into the nines....know i will need no c clips ,,i waste more dam money let me tell you ...............

 

Keep the 28 spline axles for now and go with the 3.73 gears. The difference in gas mileage is negligible between them and 3.55 and the 3.73's are a lot more fun to drive.
And NOS/MAN you really need to lose those C-clip axles and get the proper axle retention types before you have a big accident.

 

I KNOW A 9 IN IS IN THE WORKS SOON ,,IF I RUN MID 9S ARE BETTER ,,IAM JUST GOING TO LOOSEN MY ROCKERS,,AND PARK IT AND KEEP THE DIAL IN ON IT ,,,THAT WAY I WONT DRAG RACE IT EVERY WEEKEND AND HURT SOMETHING ON IT.....IT WILL REST FOR AWHILE ,,WHILE I REST I WHILE,,,,I CAN JUST SIT BACK AND THINK ABOUT WHAT IT RUN ,,LET IT SOAK IN ...YOU DO THAT ,,,LIKE DAM I CANT BELIVE IT ,,,

 

REST IS GOOD.