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View Full Version : Wheel Hop!!!


cobra2112
11-09-2004, 12:35 PM
I have recently installed some bolt on peformance stuff on my 04 cobra and very dissapointed in the wheel hop issue. Almost to the point where I don't enjoy the car anymore. I just installed the Kenny Brown stiffner bracket with poly bushings with almost no difference in wheel hop. I have read some articles describing some fixes but I see there is nobody has a true fix to this problem so far. I would like to hear form some people who have some exprience fixing this problem with cars running in the upper 400hp range. Thanks again for all your help guys. :thumbsup:

ORANGE CRUSH
11-09-2004, 03:53 PM
The combination I have is KB subs and KB alum Diff bushings. This has lowered my wheel hop considerably. Now, I am in the lower 400hp range with stock tires so I don't know how this would compare to yours. I have heard some get less wheel hop with stickyer tires like Nitto's.

I have also had a lack of input on this subject.

Firme
11-09-2004, 04:31 PM
from what I have seen, there are 4 variables that contribute to wheel hop.
-springs (too low of a rate and they are too soft and allow hop)
-dampners(too low of a rate and they allow up-down travel too easily
-bushings (rubber are not sturdy)
-play in the differential.

to remedy this... do the following

-intall lowering spring with a higher rate than stock... at least 650lb-700lb rate
-put on some decent shocks to help dampen the oscillation
-install Steeda Differential Bushing to keep the differential from having too much play in the IRS craddle (you might wanna check the 04's since they are rumored to have some urethane in the IRS)
-install Maximum Motorsport IRS bushings(Urethane, or find some delrin/aluminums if you are hard core) to keep IRS sturdy on the body(very time consuming, and I will leave this as the last step)
-install upper and lower control arm urethane bushings (Delrin for the hard core) (you might wanna check the 04's since they are rumored to have some urethane in the IRS)
-You can also replace the differential itself, as the stock one seems to pulse power from left to right, instead of providing even power to both sides constantly. If you Road race, you can get the T-2R (http://www.globalwest.net/torsen_traction_differential.htm) or get a good spool if you are hardcore drag racer


People have had luck eliminating wheel hop by doing only part of the things I mentioned. Do them in the order listed and stop when wheel hop is gone :) :thumbsup:

and as Orange Crush stated, subframe connectors are a must on any current mustang

smashedheadcat
11-09-2004, 05:11 PM
In my opinon, it's a complete waste of money on the IRS. The car was designed to have a solid axle in it, not the IRS. The IRS rides nice, but so do solid axle cars. To make the IRS work for you (reliably) you'll need some beefier half shafts (DSS Level 5's are about $1800), bushing kits are in the $350 range, stiffer springs are about $200-300, "wheel hop shocks" are about $400, and a dif brace is about $100. Add that up and you've got a helluva lot of money in that dang thing. Also, a stickier tire will help as well.

Now, you can get everything and I mean everything (a complete down to the bolt solid axle swap with your choice of gears, axles, diff unit, shocks, springs and control arms for around $4500 installed........ PROBLEM SOLVED!

(or at my powerlevel 400rwhp 370rwtq, a set of nitto 315/35 17's fixed mine)

kilroy
11-09-2004, 06:50 PM
I would like to hear form some people who have some exprience fixing this problem with cars running in the upper 400hp range. Thanks again for all your help guys. :thumbsup:My car wears new OEM F1s and should I stab it on the street it's spin city but on the track they'd wheel hop. Buying a set of BFG DRs solved the hop issue & I picked up a few tenths as a bonus. My IRS remains as delivered by FoMoCo.

InfamousSVT
11-09-2004, 08:08 PM
I've got the MM Full-Length Subs and H&R springs, so hopefully that'll help with some of my wheel hop! I'm getting it installed by the end of the week. If not considering purchasing a hard-launch kit?

cobrabitn
11-09-2004, 08:28 PM
Thanks Kilroy! You hit the nail on the head!

How I eliminated my wheelhop on my 1999 Cobra by Cobrabitn....

One day I went to the dragstrip with my new 1999 Rio Red Cobra. I was all excited and never ran on a real dragstrip before. My gut (big one) was wrenching with butterflies as I approached the lights. I waited with anticipation as I watched the yellow lights illuminate in a downward order with the final destination being the green one. As it hit the last yellow light, I let out on the clutch and on the green light I hit the gas, and I hit it hard. All of a sudden my docile Snake became like a professional basketball player dribbling a ball. The car shook with anger and shuddered like a dog that is sheding water after he just jumped in the ocean and came out to dry off. I had the dreaded wheel hop!

I was astounded and embarassed at the same time. Shocked and bewildered that my true champion could not and would not cut it on the track. After I let off the gas, the angry reptile settled down to a 14 plus second pass. Frustrated and hopeless, I drove it home with the thought I have to get this fixed. After some Internet research and advice from fellow snake owners, I did one thing at a time till I eliminated the hop. So here goes....

A) get some stiffer bushings. ( I recommend Steeda polyurethane bushings $45.00)

B) I lowered my car 1.5 inches with a set of KB lowering springs (Which I have for sale for any 99 owner)

Before I get to C, I will state that by doing these two things, my street wheel hop became a street spinout and burn rubber session. No basketball dribbling.

C) If you plan to take your IRS equipped Cobra to the dragstrip, invest in a set of drag radials or slicks on a spare set of rims. I did, and it was the best thing I ever did. The times on my 1999 went down .4 of a second just by changing to drag radials and after the car was lowered. Set your pressure to 16 - 18 lbs of air and you will be on your way without the dreaded hop.

At last weeks drag day, I didn't experience any wheel hop in my 04 Mystichrome. I will add that I launched in between 3500 and 4000 rpms and slipped the clutch a little. It was all go and no hop.

Try these two things and see if that will help you to love your Cobra again.

In my personal experience I did not need the following:

IRS brace
HD half shafts
Subframe connectors
bushing kits

While all of these can aid in the rigidity of your vehicle, they were not necessary for me. Also, try to remember that for every action there is a reaction. You stiffen this, you put stress on something else.

JMHO! :D

coleman
11-09-2004, 08:38 PM
I've heard that Nitto DRs help quite a bit.

cobrabitn
11-09-2004, 08:42 PM
By shear coincidence... my radials are Nittos! :clapping:

Coleman :chairshot: Cobrabitn

InfamousSVT
11-10-2004, 03:29 AM
A) get some stiffer bushings. ( I recommend Steeda polyurethane bushings $45.00)

B) I lowered my car 1.5 inches with a set of KB lowering springs (Which I have for sale for any 99 owner)

Ok so I should get the polyurethane subframe bushings? I've already got the H&R springs, MM C/C plates, and the MM full-length subs! That should take care of the wheel hop for the street and a set of DragRadials for the track, right? :rolleyes: Hopefully!

Haven't got anything installed yet, but do when you said that if you stiffen something here, you put stress on something else, so will the subs be a problem?

jack
11-10-2004, 09:48 AM
All i have is a pulley, air filter and programmer. The BFG's did the trick for me. Before i had wheel hop :bounce: on hard pulls(on the street). I would invest in a drag radial first and tune from there.

cobrabitn
11-10-2004, 09:06 PM
Subs are a good addition especially if you like to rotate tires a lot like I do. :D

cobra330
11-10-2004, 09:40 PM
Ok so I should get the polyurethane subframe bushings? I've already got the H&R springs, MM C/C plates, and the MM full-length subs! That should take care of the wheel hop for the street and a set of DragRadials for the track, right? :rolleyes: Hopefully!

Haven't got anything installed yet, but do when you said that if you stiffen something here, you put stress on something else, so will the subs be a problem?

That the set up I was thinking of going with on my 04...Let me know how you like that set up when you get it installed...This is one of the next areas I will be addressing...

InfamousSVT
11-13-2004, 04:51 PM
That the set up I was thinking of going with on my 04...Let me know how you like that set up when you get it installed...This is one of the next areas I will be addressing...
I'll let you know, I should be getting everything installed sometime next week! Probably Mon. - Tues.

speederdoc
11-14-2004, 01:20 AM
My wheelhop is the worst when accelarating hard from a stop and turning, such as any turn from a stoplight. Before I bought the car, I envisioned a sort of power oversteer Viper-like spinout might be my biggest worry with that scenario.

Instead, it is a horrible bouncing and occasional scary loud THUMP. so I don't do that anymore, just kind of baby it around the turn. I'm gonna have to look into the options above.

Twice Bitten
11-15-2004, 11:17 PM
Delrin bushings help :thumbsup:

InfamousSVT
11-24-2004, 01:53 AM
That the set up I was thinking of going with on my 04...Let me know how you like that set up when you get it installed...This is one of the next areas I will be addressing...
Mike,

I finally got my car back today (Tuesday), from getting everything put on! I got the MM full-subs, MM C/C plates, Steeda Differential bushings and rear subframe bushings, with HR springs! Gotta say I'm very impressed and happy with the set-up:thumbsup:! It was a bit rainy here the past few days, but I let her rip a few times and absolutely no wheel hop!! The ride is better than stock and I feel so much more sure footed about what to expect from the car when I hammer the gas. I also put a set of 10.5 in the rear with some 315's! In my opinion it looks sweet as hell, the Steeda Rear Sub-frame bushings include a low profile bolt to help with clearance for wider tires and I have no rubbing and no wheel hop! I had to put a small 1/4 spacer in, but that don't bother me much, still rides great!:thumbsup: :thumbsup: :bounce:

Hope this helps in your search for your right set-up!

-J

NewFoundPower
11-24-2004, 09:31 AM
Post some pics when you can. I wanna check it out.


-D-

InfamousSVT
11-24-2004, 06:06 PM
Post some pics when you can. I wanna check it out.


-D-
It's been rainy for the past few days, but I hope to get around to getting some pics this weekend! I'll keep you all posted!:thumbsup:

kilroy
11-24-2004, 08:47 PM
I also put a set of 10.5 in the rear with some 315's!~the Steeda Rear Sub-frame bushings include a low profile bolt to help with clearance for wider tires and I have no rubbing ~I had to put a small 1/4 spacer in, but that don't bother me much, still rides great!
-J Would the tire still rub without the use of .25" spacers? :scratch:AFS 10.5 wheel?

InfamousSVT
11-24-2004, 09:35 PM
I'm not really sure, the bolt from the Rear Sub-frame is the only thing that will hit the tire, everything else is out of the way! I installed the Steeda bushings which include a low profile bolt to replace the stock bolt which is about a 1/4" shorter! I put the H&R Springs on it, which lowered the car approximately 1.5" which made the rear move down, which in-turn causes the bolt to be inbetween the rim! I can look through the rim stars and see the bolt! The only way it would have contact is if you were to hit a major bump and cause the rear-end to jump up and hit it!!

Also, it depends what kind of tire you are running, cause some tires run wider than others! I'm running the Goodyear Eagle F1 GS-D3, but I beleive the Nitto's run a little bit smaller, if you have considered those!

I'll be posting some pics of everything over the weekend so come Monday you can view them! You will probably have a better understanding of what I'm talking about with some pictures to see!:thumbsup:

Hope all this rambling has helped in some way or another!

93KingCobra
11-25-2004, 12:51 AM
From my personal experiance I have had wheel-hop also and all I did to correct it was get some Nitto DR and lowered my car with H&R's SS.. I have not had many problems after that if I do have some coming out of the box than I just push the clutch in and let it the RPM come up to stop it....Oh and LET OFF THE GAS it will save your rear end.

kilroy
11-25-2004, 01:30 AM
As I said before, a set of DRs cured all my wheel hop blues. OK to stiffen the IRS up, but not a necessity, IMO.

A Little off topic, but I was very interested last year in a set of 10.5 AFS wheels until I learned the backspace issue necessitated the use of spacers. I have a friend who went that route & at 45-50 mph it shook so bad he thought he had a tire going down. He un-modded the same day.:what:

Post up the pics InfamousSVT when you can. I'm sure it looks awesome - I just hope you don't have the same experience my friend did with his spacers.

cobra2112
11-25-2004, 04:57 PM
How well do the Nitto DR perform in conditions other than straight line driving? Like cornering, rain etc.

cobra330
11-25-2004, 05:37 PM
Mike,

I finally got my car back today (Tuesday), from getting everything put on! I got the MM full-subs, MM C/C plates, Steeda Differential bushings and rear subframe bushings, with HR springs! Gotta say I'm very impressed and happy with the set-up:thumbsup:! It was a bit rainy here the past few days, but I let her rip a few times and absolutely no wheel hop!! The ride is better than stock and I feel so much more sure footed about what to expect from the car when I hammer the gas. I also put a set of 10.5 in the rear with some 315's! In my opinion it looks sweet as hell, the Steeda Rear Sub-frame bushings include a low profile bolt to help with clearance for wider tires and I have no rubbing and no wheel hop! I had to put a small 1/4 spacer in, but that don't bother me much, still rides great!:thumbsup: :thumbsup: :bounce:

Hope this helps in your search for your right set-up!

-J

Thanks Infamous SVT...I will be doing the MM full-subs, MM CC and H&R SS for sure...Now if I could just get work to cooperate so, I have the money that would be great!

Oh 1 question though..which part number did you use for the MM full subs? Thier website was not specific..so, I want to make sure I get the right ones...I assume they are the same for a convertible as the coupe....

InfamousSVT
11-25-2004, 06:57 PM
Thanks Infamous SVT...I will be doing the MM full-subs, MM CC and H&R SS for sure...Now if I could just get work to cooperate so, I have the money that would be great!

Oh 1 question though..which part number did you use for the MM full subs? Thier website was not specific..so, I want to make sure I get the right ones...I assume they are the same for a convertible as the coupe....
The part number I ordered was MMFL-3PC , and I do believe they are the same part number for the vert as the coupe! I got the powder coated, which is the part number I gave you! They are also available in bare steel, which you will have to paint (protect) later after install! Good luck!
If you're not sure before ordering, I'd send them an email. Great customer service!!:D

InfamousSVT
11-26-2004, 05:59 PM
=kilroy Post up the pics InfamousSVT when you can. I'm sure it looks awesome - I just hope you don't have the same experience my friend did with his spacers.
As you have requested here are some pics of the 315's on 10.5" rims!:thumbsup:

The Rear Sub-frame bolt that most people have problems hitting the rim/tire, has been replaced with the Steeda low-profile bolt that they supply with the Bushing kit they sell! You can view this in the last photo (bolt on the top left)!:) :)

kilroy
11-26-2004, 07:25 PM
The Rear Sub-frame bolt that most people have problems hitting the rim/tire, has been replaced with the Steeda low-profile bolt that they supply with the Bushing kit they sell! ~:) :) Way Cool, Jr.:cool: Looks nice! What in particular made you decide to use spacers? Did you try the combo without them initially, or no?

InfamousSVT
11-26-2004, 07:38 PM
Way Cool, Jr.:cool: Looks nice! What in particular made you decide to use spacers? Did you try the combo without them initially, or no?
I didn't try it without spacers, because my cousin (works at ford) said that the up and down movement with out the spacers would cause the rim to rub against the bolt. Which it wouldn't rub that much, but I just don't want to chance it!
It works great and can't even tell a difference in ride with the spacers. No longer shafts or anything required!:thumbsup: