hey guys i am new to the irs on the cobras. i was wanting to know the differences between the 99/01 irs and the 03/04 irs? what makes one better then the other? thanks
irs question
- Thread starter saleen2002
- Start date
In 1999 the halfshafts on the IRS contained a 28 spline inner shaft. This is determined by the gear carrier inside the differential. The 28 spline halfshafts were the weakest halfshafts of all IRS years. In 2001 the halfshafts were beefed up slightly and the inner spline was updated from a 28 to a 31 spline. In 2003 the halfshafts were once again upgraded to a heavier unit but still retained the 31 spline inner. ALL halfshafts from ALL years retain the same 28 spline outer that goes through the hub in the rear knuckle.
The early 1999 and 2000 Cobra R models had knuckle cross axis joints that were pressed in and did not have a flange and retaining ring holding them in. These were all recalled and updated with the retaining ring style cross axis joints.
The biggest problem all IRS owners have is neglecting to keep the rear hub to halfshaft retaining nuts torqued to 240-250# on a REGULAR basis. The torque is required for bearing pre-load. This neglect leads to destroyed rear knuckle bearings and damaged rear hubs.
FWIW
:thumbsup::coolman::beer:
ok thanks. so would you pick up a 99 irs for 350 complete?
If I were you I would look for a 03/04. FYI, the gear ratio was also 3.27:1 in 99. The 03/04 cobra is 3.55:1. Also the 03/04 cobra has a stronger differential crossmember. Which ever one you choose make sure to talk to ac427cobra about his bushings.
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^+1 I would avoid the '99 unless you picked it up real cheap. The '03-'04 is a much better choice.
:thumbsup::coolman::beer:
ok so i am gonna pass on the 99 irs.....how much is is a good price for a 03/04 irs? any one selling one? thanks
You won't have to wait long. Just hang out here for a few days. Someone with a case of straight line fever will gladly trade the IRS out of his Cobra for you stick axle :nonono:
Thus slowly beginning the Cobra to Mustang GT conversion! ;-)
Search craislist in the S.F. bay area, type in "cobra mustang". There is a guy in Pacifica who has an 03/04 complete IRS assembly for sale. I can tell from the pics that is an 03/04 because of the pinion support design.
Good luck!
any one in the sf bay area looking to do a irs to sra trade?
pm sent!
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