IRS hopping

Regan3521

Regan3521

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I wanted to know what is the best way to get my IRS to stop hopping, I have a 2003 Cobra drop top and I want to keep the IRS but I want it to hook up. This is my first IRS car and I’m not filmier with them too much. I dont want to put an SRA in if i can help it.
 
PWORLDSTANG

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Those bushings will work well, but I'd try some new tires first. A lot of guys who have wheel hop get rid of it with a good set of drag radials.

Based off your numbers you're pullied, so I'm just going to assume you're on street tires. I'd recommend getting the Nitto 555R drag radials. Those should get rid of most, if not all of your wheel hop. If you still have wheel hop after these tires, lots of guys have successfully eliminated wheel hop with the combination of drag radials, subfram connectors, and lowering springs.

My car has subframe connectors, lowering springs, and BFG drag radials. I don't have any wheel hop at all. The car will just spin before it hops.

However, before I added my BFG's, my car would hop like a ****in rabbit on Kumho street tires with subframes and lowering springs in first gear and sometimes second. Try some drag radials first, they should definitely work for you.
 
Regan3521

Regan3521

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She also has 4.10+ rear gears will that be an issue if i do any of these things. I also having a problem hopping bad in second too FYI.
 
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thomas91169

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wow, whoever decided to put 4.1's on a 03/04 cobra for anything but track use was smoking the good stuff. thats gonna hamper traction in 1st-3rd gear really no matter what.

Get a good set of drag radials under the car, and go from there. Tires alone will probably cut out 75% of your hop and traction issues, the other can be solved with springs/shocks and bushing kits.
 
BO TY KLR

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I have been lowered with H&R SS since the car was a month old. Never had any wheel hop. Stiffer spring rates will help. The verts have a softer rear spring than the coupes and my H&R are stiffer yet.
 
FromGTtoSVT

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get better springs, better tires and subframe connectors and it should take careof most of the hop problems you have

there are definitly more radical ways of putting an end to it like replacing bushings, but what I have listed above will work really well with out getting to deep into the IRS.
 
Blade Runner

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SLEEPERSTATUS said:
GOOD POINT IM RUNNING SOME CHEAP SUMITOMOS WHICH TEND TO SPIN EASILY LOL BUT NEXT TIME I WILL DEFINATLEY BUY SOME DR'S:beer:
Click to expand...

STOP YELLING, YOU'RE SCARING THE CHILDREN!!!!! LOL.......But seriously, I have the same damn problem with the rear-end hop. I just have to go through slightly different channels to correct it.
 
ac427cobra

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PWORLDSTANG said:
Those bushings will work well, but I'd try some new tires first. A lot of guys who have wheel hop get rid of it with a good set of drag radials.

Based off your numbers you're pullied, so I'm just going to assume you're on street tires. I'd recommend getting the Nitto 555R drag radials. Those should get rid of most, if not all of your wheel hop. If you still have wheel hop after these tires, lots of guys have successfully eliminated wheel hop with the combination of drag radials, subfram connectors, and lowering springs.

My car has subframe connectors, lowering springs, and BFG drag radials. I don't have any wheel hop at all. The car will just spin before it hops.

However, before I added my BFG's, my car would hop like a ****in rabbit on Kumho street tires with subframes and lowering springs in first gear and sometimes second. Try some drag radials first, they should definitely work for you.
Click to expand...

Eliminating wheel hop is only part of the equation. Sure it's a good thing to eliminate it but that is just the beginning. Tires, springs and shocks are a nice start but certainly are nowhere near the complete and total answer.

For instance, reducing or eliminating wheel hop will not protect your differential from leaking, cracking or breaking the rear cover. The differential needs to be stabilized and reinforced to prevent that.

Eliminating wheel hop is not addressing the severe range of motion the control arms are able to travel with the soft, compliant factory rubber bushings they are mounted in. As well as the subframe mounted to the chassis with rubber bushings. All of these areas are working against you when you try to apply a lot of power down.

I recently disassembled an IRS and made a pretty gruesome discovery. The differential housing had a considerable amount of play in it. So I captured it on video here:



Differential mounted rubber as delivered from the factory

Just some food for thought!

:thumbsup::coolman::beer:
 
03cobra#694

03cobra#694

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All I get is a pic no video from thishttp://fulltiltboogieracing.com/images/IRSDiffMounts.JPG
Am I missing something?
 
03cobra#694

03cobra#694

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ac427cobra said:
The control arms pretty much do the same thing in the factory rubber bushings. :eek: I just have not had a good opportunity to capture it yet.
Click to expand...

Do you think the more miles on the car,the worse it gets?Mines only hopped a few times,I have 15K on it.
 

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