View Full Version : 03 irs

09-12-2007, 07:43 PM
I have an 03 cobra with the stock irs rearend, Im making 500hp with 472lb torque. I like from time to time to run my car at the memphis motorsports part on test and tune night and my problem is wheel hop, and alot of it. Ive been told the only way to fix my problem is to go to an 8.8 rearend, well ive recently gotten some information on a grip box package from Maximum motorsports for about 900 bucks that they say will stop the hop and allow me to launch the car at 3 to 4000 rpm and hook. Anybody heard of this or have a suggestion on what I can do to stop my hop and hook? Thanks inadvance folks!

09-12-2007, 08:27 PM
Delrin bushings for everything in the rear, stiffer springs if you are still on stock ones, full length subframes, irs differential brace, and drag bags. Go to Maximum motorsports for everything except the bags ... go to Laurel Mountain Mustang for those ... $60.00 per pair and air up to 3-8 lbs of air.

09-12-2007, 09:32 PM
Thanks alot ! It would seem im on the right track thanks for the advice puzzle13.

Big T
09-12-2007, 11:19 PM
I've heard the bags help alot. I'm going to get some soon.

09-13-2007, 08:01 AM
You did not mention if you are running street tires or D/R's or if you have a aftermarket clutch installed. The reason I say this is because I have been reading about this alot lately on svtperformance.com and alot of people suggest using D/R's which will help alot. The other is if you have a spec 3+ clutch or a clutch just like it then it is either on or off with very little slip. Alot of people are going with the spec2+ that is less agressive and have no wheel hop at all. Again this is all from reading and hope this has helped out some.:thumbsup:

09-13-2007, 09:05 AM
Puzzle gave you some great advice...I did springs, bushings, KB matrix subframe system and D/R's...this got rid of my hop (really just spun more than hopped)...you can swap out to a straight axle if you want, but the ride quality is no where near the IRS :thumbsup:

09-13-2007, 11:00 AM
Straight Axle!!!

09-13-2007, 02:00 PM
I have Nitto DR's, MM FLSFC's, MM Coilovers with the performance street settings and Bilstein sports shocks and struts valved to their numbers, MM tie-rod ends, MM subframe brace, the right size bolts in the rear subframe and ac427cobra's(off svtperformance) complete rear bushing kit, and so far I haven't had a probably with wheelhop. It really improved the handling but you will pay for it in ride comfort. Its not harsh, but I wouldn't want to take a long road trip in it either. You'll be worn out by the time you get there. :thumbsup:

09-13-2007, 06:06 PM
Thanks for all the suggestions, I am running sumitomo street radials 315's 10.5 wide and the clutch is aftermarket but I dont know it the imput shaft has been changed out or not so if i do run drag radials im going to run mt street et but not before i find out about the input shaft. Main thing is money the irs is in the car and may as well be used, so best thing is to make it work, but the entire thing is stock so alot of work seems to need to be done. anymore suggestions are more then welcome and thanks again.

09-13-2007, 10:19 PM
puzzle do you know how easy or difficult the bags are to install??

09-14-2007, 07:56 AM
real easy! Just take off the tire, scrunch up the bag really well just like the directions say and with the careful help of a screwdriver it takes just a few minutes. The harder part is attaching the lines as there is not much room for your fingers to work, and then deciding how your are going to run the air lines. My kit did not include a tee, but I purchased one for a buck and teed mine inside the trunk. I had to drill 2 holes, but it is all but invisible.