Claude, not sure on your car with the 5.5 backspace. I am having the rear end cut down a little also. That will have an effect on what backspacing you will need.
My wheels have a rear spacing of
4.5", not 5.5"...I never planned on narrowing the stock 8.5" differential. Instead, I'd rather sell it complete (already has some Moser spool and axles) and replace it with a Ford 9" also with spool and axles and the correct bracketry to install some Baer or Aerospace disc brakes, but with
two (2) calipers to be able to launch with high boost without using the trans-brake ('cause trans-brakes are not allowed in some classes around where I live
If you want to use a "t-b", it's your choice, but they'll put you in a class in which you'll have to run against a bunch of dragsters with delay boxes and throttle strops, etc, no thanks, not for me :frown:...
Whew!...that's going to be lot to do at the same time...tubbing the car, changing the rear axle, getting new wheels and tires and dual caliper brakes!...
One last thing I noticed...You said you were going to use some 325-50-15 tires...Is there a reason why you didn't choose to use some 390-45-15's instead? I thought that if I'm going to tub the car to use big tires, I might as well go with HUGE ones!...:biggrin: These would need 12" wide rims though...
See link:
(c) 390/45R15
Thanks,
Claude. :wink: