Backspace to fit 12" rim on mini tub foxbody

[NightMare Fox]

33 will be fine for that power range, but at 1500, you will probably destroy the 33s and need to go to 35s. Also for the 12" with 6.5" bs, bring the 9" end all the way to the lower control arm mount. That distance may vary depending on the rear end, but it is likely around 2-2.5".

Ok maybe I should just go with the 35 than as I'm sure she will be turn up at some pointe building the motor to handle 1400-1500 never know where I might end up ..better safe than sorry

[Fryguy302]

Ok maybe I should just go with the 35 than as I'm sure she will be turn up at some pointe building the motor to handle 1400-1500 never know where I might end up ..better safe than sorry

Makes sense. On mine, I went through 31s, 33s, and now 35s.

[NightMare Fox]

Makes sense. On mine, I went through 31s, 33s, and now 35s.

nice not looking to keep replaceing lol....thanks again Raj

[Billydroveit]

ok so you guys are saying 2.5" total 1.25" per side shortened......with a 6.5 BS....here is my next question what spline 33? im doing a stroked LS lq4 6.0 and adding a 88mm turbo looking around the range of 1000HP thanks for any info

2.5 each side Liek Raj said it bring the end flange to the lower mounting point.

[NightMare Fox]

2.5 each side Liek Raj said it bring the end flange to the lower mounting point.

I do not see where Raj said to do 2.5" i am seeing 2-2.5" is about what is needed....Billy is your car mini tubbed? if so is that what you did 2.5" ????

[Billydroveit]

. That distance may vary depending on the rear end, but it is likely around 2-2.5".

My car is not mini tub, but i did my homework when i was looking at that route.

[Billydroveit]

SO if you measure where the flange is now, to the lower controll arm mounting point it ends up being 2.5 is usually the max you can take off and still be able to use the standard mounting point. Now take what a factory set up is with a 10" wheel and it needs a 6.5 backspace. So to add 2 more inches of rim will require a minimum 2" less axle length. Now factor in afermarket brakes are usually thicker than teh drum set up so you want to also compensate for that in the process and buy yourself as mush sidewall room you can since usually you lower the ride height at the same time which means you have to clear the bubble of the side wall at a wider point, thus using up that extra 1/2" over the 2" required just to clear the added rim width.

[NightMare Fox]

SO if you measure where the flange is now, to the lower controll arm mounting point it ends up being 2.5 is usually the max you can take off and still be able to use the standard mounting point. Now take what a factory set up is with a 10" wheel and it needs a 6.5 backspace. So to add 2 more inches of rim will require a minimum 2" less axle length. Now factor in afermarket brakes are usually thicker than teh drum set up so you want to also compensate for that in the process and buy yourself as mush sidewall room you can since usually you lower the ride height at the same time which means you have to clear the bubble of the side wall at a wider point, thus using up that extra 1/2" over the 2" required just to clear the added rim width.

ok great info there i apreciated it....thanks Billy