Exactly how much will the 99 IRS handle?

It seems like the 03 & 04 just grips much better than my 99. Im workin with about 480rwhp now, what can i do to make my suspension comparable to the 03 & 04's.
If anyone has a 99 and would like to share a story with me about their suspension successes and errors, please feel free.
 
Well I don't own a Cobra but I might be able to offer some advice. The newer Cobra's use a higher duromater bushing in the mounts and arms,and that's what is actually "jumping" when the axle hops. There are companies out there that offer eurathane replacements that are supposed to quell the hop. I'd start with Energy Suspension and just keep looking from there.
 
Are you asking how much will they handle on the drag strip? If yes, not much more than you're putting to the rear wheels right now. Half shafts aren't that stong. I've talked to several 03 and 04 Cobra owners who have blow their rear axles apart at the track this year. I'd swap in a solid axle if you plan on putting much more power to the ground. IRS axles(all axles for that matter) make a BIG MESS and make people wait in the staging lanes for a long time when you blow them at the tree! :bang: :nono: :damnit: