MM IRS bushing Installed and Wheel Hop Still There...

[stangfan]

Granted... It dosen't seem as 'violent'. But, it's still there.

Anybody out there install the Steeda rear diff & MM IRS bushings and still have 'bad' wheel hop?

Could it be that it's a convertable? With Steeda 'Cobra Sport' springs? :shrug:

I'm just a little disappointed right now... I read all these posts about people installing the Steeda rear diff bushings & MM IRS bushings and there wheel hop is 'gone'?

All I ask for is the ability to enjoy 'all' this power that my motor's making :gt: I don't want to have to swap out the IRS for an 8.8 solid rear... The IRS is part of the reason I bought the Cobra...

I wander if some adjustable rear shocks (QA1) and some Nitto 555R's will help?

 

[03Steve]

QA1's will help. The red car in STL runs QA1's and the Steeda bushings. 1.4 60'.

 

[Cobra10thaniv]

Watch out for the steeda dif bushings sitting flat I noticed that on mine. They sat on the non machined flat and I could slip in a putty knife between the bushing and the pumkin flat.. Im sure thats not the only reason why your car might hop though just somthing that happened on mine. BTW mine hops

Have you thought about the upper and lower arm bushings?.

 

[stangfan]

Have you thought about the upper and lower arm bushings?.

Who makes them? I haven't seen them yet... At this point, I'm willing to try just about anything. Since I've installed the chip/pulley, I can't even go WOT in 2nd until about 5K withouth hopping. Even then, sometimes it'll hop.

The way I see it... I have 3 more options.

1)QA1's adjustable rear shocks
2)Some DR's for better traction
3)Swap out the IRS for a solid rear.. (I don't want to do this...)

 

[03DOHC]

Hmm, I haven't really had a problem with hop since the weather warmed up. Mine mostly hops when it's wet or cold outside.

I read about the rear subframe bolts being undersized. Maybe you can do a search on 14mm bolts. I think they have 12mm bolts in 14mm sleeves or something like that.

 

[Cobra10thaniv]

I thought I seen them in the MM cat. And there is anther catalog that has them I cant remember who they are, Just there stuff was pricy. If it comes to mind I will pm you.

 

[03Steve]

Bushings are foo foo. You need shocks. Solid is best though...

 

[Cobra10thaniv]

Originally posted by 03Steve
Bushings are foo foo. You need shocks. Solid is best though...

I have heard that about the shocks also. If you read about the posts where somone said they have fig out that the tire walks forward and hops kinda like a wiggle and hop going on after i lost it grip then walks forward again and all over.

Although I would bet the shocks keep the tire to the ground but the walking still happens. Dont this suck on a 40,000 car

 

[bborder]

I installed the IRS bushings when I had close to stock horsepower and they eliminated most of the wheel hop. However, now that I've added 100hp they don't seem as effective. Still a big improvement but not 100% cured. So, my next step is higher rate shocks to go with my coil overs. Hopefully some Cobra R shocks in the rear and Bilstein Race Struts in front should solve the problem.

 

[maoun]

i put coilovers (koni dual adjustable shocks) with 550 springs....griggs delrin bushings...mm bushings...SFC

and yes, still have wheelhop

i agree with brian (bborder)....on stock horse, they do good work....but not much more.

m.

 

[Cobra10thaniv]

Originally posted by stangfan
Who makes them? I haven't seen them yet... At this point, I'm willing to try just about anything. Since I've installed the chip/pulley, I can't even go WOT in 2nd until about 5K withouth hopping. Even then, sometimes it'll hop.

The way I see it... I have 3 more options.

1)QA1's adjustable rear shocks
2)Some DR's for better traction
3)Swap out the IRS for a solid rear.. (I don't want to do this...)

I think I found them for you, Look down under 99+ cobra IRS

http://www.griggsracing.com/gr40drag2.html

Delrin Rear Control Arm Bushings (IRS only) MCA 99 IND $ 379.95

If it works let me know or post it, makes sence though if those are soft. They all can make the suspension loose.

 

[Grover03]

My hop didn't go away until I went to the BFG's

Grover

 

[Sin]

Steeda stuff...you know Gus

 

[KiLLaBytE]

MM IRS Bushings and Kenny Brown IRS Brace are installed. Still have wheelhop. Going for MM full-length weld-on subframes soon, we'll see how they do.

 

[hockeypuck_74]

I've got the MM IRS Bushings and Nitto DRs. I've been thinking about the Griggs coilover. Maybe I'll just do the QA-1s.

 

[Cobra10thaniv]

I have seen some of the pics of the wider tires and they say they dont have hop once they went wider.

One major thing I noticed was on some not all but they are mounted on our 9" rim going as wide of tire as they could. Well the tire crown is so terribly.

I would bet they dont have hop cause there contact area isnt the same as our poor F1's heavy contact are is in center if tire.

Even though tire manufacture says it fits on a rim doesnt mean it optimal.

So with that in mind I seen crown tires on some of the Cobra cars now. I wounder if the same thing is going on? GO wider tires and that stops my wheel hop doesnt make much sence to me Just my .02 worth its only somthing to think about

 

[toofast4u]

I have one of the higher HP cars here and don't have any wheel hop. When you did the MM IRS assembly bushings did you replace the stock 12mm bolts with the correct 14mm bolts? The stock crush sleeves and the MM IRS crush sleeves are both for 14mm bolts not the 12 mm bolts the 03 Cobra comes with. The 99-01 Cobras did come with the correct 14mm bolts. These can be purchased at Ford for a 99-01 Cobra or through MM I think they only cost something like $10 for the pair with nuts. I did have some hop before I replaced my 12mm bolts and they do make a major difference.

I am also running 650# MM coil-over with 00R shocks, 555R 315s @ 26psi, and full length subframe connectors. I don't believe the coil-over and shocks are necessary to control the hop, but did my entire suspension at the same time so I can't quantify that. Now when I spin my tires they just go free like with my old 95 Cobra with a solid axle.

 

[hockeypuck_74]

I don't believe they changed the bolts, no.

 

[racerat]

The cold weather is back and so is my hop. Yesterday I wheelhopped so violently it shattered a foglight. :nonono:
I can't go WOT till halfway through 3rd gear.
I have the steeda bushings, MM bushings, couple rear springs and anti-hop shocks. BFG DR's didn't help, Nitto DR's didn't help. A solid rear is gonna help as soon as I break these halfshafts, which I fear won't be long.

 

[toofast4u]

The correct 14mm bolt part number is N811315S428 and it is a Ford part for this location and is available at Ford Dealerships.