Hello everyone.
I am about to get back to my rx7 project.
It is wide body 12A Turbo (aggresive street port)
It is dropped and has a camber plates
It will have turbo 2 trans (now stock)
I has custom compo-motive rims with mustang 5 bolt pattern. These are 16"Rims with 225 front and 245 rear width.
subframed 4 link.


i am trading extra rear end that i have-chevy 10 bolt,for mustang rear (8")with a shop that was many mustang rear options.

I know the width of fox body rear is good, bolt pattern is wrong (I need post fox 5 bolt)
I Know i want discs etc...(and i might have to buy new axles and brake kit aftermarket)

how about gearing???
i have done some research before, and i found that for my 12a turbo application 2.85 gear ratio would be good. 3.00 or higher would be good for srtip, but i want streetability
I know that there are calculators and equations to estimate gear vs, tire size ratio, but i am not too good in mathematics
Please help

 

well isn't the stock ratio of FBs 3.99 or something close to that. A 3.31 Would be good.

 

thanx, just remember almost nothing in my application is stock, so its not compatible to fb transaxle
note. I will be using MUSTANG 8.8 rear!

oopsss.. i just realized i did mean 2.8 or 3.0 gear ratio- that makes no sense at all...

i need more input, thanx guys

 

Typical 86-93 Mustang 8.8s came stock in a four lug with 28 spline axles, drum brakes and Ford's LSD called Trac-loc. 5 speed cars came with 2.73s; auto cars had 3.27s. An option for the 5 speed cars was 3.08s. The 94-98 cars used the same 8.8 housing as the earlier cars, but .75" longer per side axles to accomodate ABS exciter rings on the axles. These also came with 5-lug, 28 spline axles and two types of disc brakes: GT/v6 10.5" non vented and Cobra 11.65" vented; calipers are the same, but the Cobra caliper cage has a support bar that is not present on the GT/v6, and the pad thickness is different to accomodate the thicker Cobra disc. Available Ford gears are all the above plus 3.55s. 3.73s and 4.10s, etc. The s197 cars (05+) have a 3.31 gear option that fits the earlier housings (these 8.8 housings mount the suspension completely differently and are wider but the GT cars come stock with the 31 spline T-loc). The after market provides abundent gear ratios as well. If you need beefier axles, the Explorer came stock with a 31 spline T-loc which fits the mentioned housings and there are both Ford and after-market 31 spline axles (also 33 spline). If width is an issue, stay way from the 99+ 8.8s - the housings are wider than the earlier ones plus the axles are another .75" wider - so 1.5" wider per side than 86-93 8.8. The 5-lug bolt patern is 5x4.5. HTH

Edit: Just remembered the 99-04 Cobras came with IRS that mounts to the stock quadra link system used on the older cars (a popular upgrade to the ealier cars); if you have torque, go with the 03/04 Cobra versions which are beefier but will still break the stubs. Also, the s197 cars used a three-link suspension system with the upper mount ear cast into the housing.