IRS went KABOOM !!!!!!!

[Ruckus46gt]

8.8 out of a 99-04 gt or mach 1 moser 31 spline axles, detriot true trac thats the way i would go. True tracs can take a beating. I used to launch on slicks at 6,300 on my little 2v. I know people pushing over 600 launchign from above 6k also with no issues

[BurnTire]

If you plan to run slicks your better off with a pre 99 housing. It will give you more wheel choices.

[Ruckus46gt]

If you plan to run slicks your better off with a pre 99 housing. It will give you more wheel choices.

if you dont mind me asking what more wheel choices will it let you ahve with a pre 99 housing? I've had 18x10.5s all the way down to 15x8s and 15x10's on my 00 mustang without modification

[BurnTire]

On a 28" slick you need a 7.0 Backspacing with a 99+ Housing. I know many people using a 6.5 inch backspacing that have to roll the fenders.

With a 98 and earlier you can use a 6.5 in back spacing.

This is not about street wheels it is about slicks and keeping the tires off the fenders on launch.

When I drop the IRS I will measure rotor to rotor and compare it the my 98 housing and see the difference. I have been told the IRS is the same width as a 98 housing.

[Ruckus46gt]

On a 28" slick you need a 7.0 Backspacing with a 99+ Housing. I know many people using a 6.5 inch backspacing that have to roll the fenders.

With a 98 and earlier you can use a 6.5 in back spacing.

This is not about street wheels it is about slicks and keeping the tires off the fenders on launch.

When I drop the IRS I will measure rotor to rotor and compare it the my 98 housing and see the difference. I have been told the IRS is the same width as a 98 housing.

how tall a tire is has nothing to do with backspacing. I ran 26"x11.5x15 et streets. Friend of mine ran 28x11.5x15's on his bullitt no rolling either.
a 15x10 prostar for a ford has a 6.5 backspacing..for a rear on a 99 up car or a 96-98 cobra
edit:
forgot to mention rolling the fenders is more of an issue with a lowered car no matter what year. Oh yea and a 6.0 backspacing will work on a 96-98 cobra and will sit flush but prostars dont come in a 6.0 backspacing

[BurnTire]

how tall a tire is has nothing to do with backspacing. I ran 26"x11.5x15 et streets. Friend of mine ran 28x11.5x15's on his bullitt no rolling either.
a 15x10 prostar for a ford has a 6.5 backspacing..for a rear on a 99 up car or a 96-98 cobra
edit:
forgot to mention rolling the fenders is more of an issue with a lowered car no matter what year. Oh yea and a 6.0 backspacing will work on a 96-98 cobra and will sit flush but prostars dont come in a 6.0 backspacing

What is this bullitt running is it pulling sub 1.5 60's and 10's?

Taller Tire = Closer to fender.

Faster Trap speed = More tire growth.

That is why a 6.5 backspacing can have issues on a 99+ Axle on 28" slicks on a serious drag racing mustang.

7.0 Backspacing moves the tire in a little more away from the fender lip, but your wheel choices are limited. Bogarts etc.

The 98 housing is 3/4 of an inch narrower per side so the tires are tucked in a little closer and the 6.5 backspacing works well with many wheel choices.


Again I am not talking about you average Joe pulling 1.7 60ft times running 11's.

I am talking about a 600+ RWHP car leaving at 6000 RPMs pulling a 1.3-1.4 60ft. Runs 9's and 10's.

I have a few buddies on Modular Fords that wish they would have done a narrower solid axle.

If you want it explained better talk to Dan.
He is the one that explained all the dimensions and backspacing to me.

[Ruckus46gt]

bullitts running 11.1@123 low 1.5 60's. I'm just leave it be no reason to go back and forth. Do know of a 10.1@1343+ twin turbo mustang gt(cobra motor with hp kit) running 28" tall tires and a mach 1 running 9.9@1345+ running 28" tires with no issues(vt 324 stroker, hp twin 57mm turbos).
edit: video...as you can tell lifted 2 times suspension is now done we will see what it does when the boost is moved up to 16psi
http://media.putfile.com/tt-mach

[Dan]

[Ruckus46gt]

nobody is saying that a pre 99 isnt narrow we all know it is. Only thing being debated on teh typical prostar 15x10 6.5 backspacing, 15x8 5.5 backspacing that a 28" tall tire will fit no issue with rubbing unless the car is lowered. I forgot though you only deal with race cars and pre 10's is slow. You have the worlds fastest 2.2 cobra etc yadda yadda. I/m not going to spend my days finding many pictures of machs, bullits , 99 up gts with 28" tall tires its no point you know everything
i bet you a think called adj control arms wouldnt change anything with fitment either would they

[wickedcobra]

WOW, So..................It looks like I only broke the girdle. All gearing and shafts look to intact. A new cover should fix it with a brace of course. The only question is weather I should still do a Solid rear. Oh and what year we use is not up for discussion HAHAHAHA.