Wheel hop questions-anyone have answers?

[Robb03]

Wheel hop pisses me off. It is cold and my snake acts like a rabbit. Does everyone have this problem in the cold, or just a select few like everything else? I have heard about Amazon's wheel hop kit. Does anyone have the stage 2 kit? Does it handle better? Is there a better one from Steeda or somewhere?
Next question, does anyone have different tires on, like the Nitto DR's. Anyone who has them, have hop with them on hard accel? I have read of a few people getting better traction with them, but would changing them solve the hopping issue? It didn't hop when it was warm in the summer, I could burn the damn things off if I wanted to. Any other options availible that I should investigate? I like the idea of a lowered car with adjustable shocks, espeically if it improves handling. I don't care if it is a stiffer ride, it isn't my daily driver. Any help would be great. Thanks!

 

[03DOHC]

If the weather cooperates I'm planning to install my HPH/AR anti-hop shocks this weekend.

 

[Robb03]

Are you doing just the stage 1, or changing the bushings and/or springs too? How long will the install take you think? Be sure to let me know how it goes!

 

[03DOHC]

Just the shocks for now.

If I had a lift and power tools not very long, but using hand tools on the ground and taking my time a couple hours.

 

[T3 Cobra]

Originally posted by 03DOHC
If the weather cooperates I'm planning to install my HPH/AR anti-hop shocks this weekend.

Are those the ones from JDM?

 

[Blackcobra]

Robb,

I asked a similar question a couple days ago, see:
http://www.svtperformance.com/forums/showthread.php?s=&threadid=26782

The short answer appears to be: there is no God (i.e., despite people taking time and effort to respond thoughtfully, no one really had answers/solutions re: kits, springs, or tires).

I'm going to try the AmazonRacing/HorsepowerByHermann set up since Hermann's shop is pretty near me and he has a great rep. I'll let you know. The kit is on-line at: http://www.amazonracing.com/page2(03cobra).html

P.S. The more I read tire threads, the more confused I get. The latest seems to be that DRs are simply great for the track but generally suck on the street unless you can get them hot. If this is basically true, then I'm staying with F1s and hoping the AR/HBH kit fixes the hop.

 

[08snake]

Originally posted by T3 Cobra
Are those the ones from JDM?

T3, that setup comes from Amazon Racing...

 

[Big Daddy]

The only thing that will totally eliminate the hop is either changing the geometry of the IRS or replacing it with a live axle. Kenny Brown has a solution they say will stop the hop by changing the geometry. Give them a call and see what you think. Hope this helps!

 

[T3 Cobra]

Originally posted by 03snake
T3, that setup comes from Amazon Racing...

I talked to Jim at JDM on Tuesday of this week and he informed me that they had the same rear shock setup??

 

[03DOHC]

Originally posted by T3 Cobra
I talked to Jim at JDM on Tuesday of this week and he informed me that they had the same rear shock setup??

The one I got came from Amazon Racing/Horsepower By Hermann.

 

[matt lankford]

jdm has tons of parts they dont have on their site, there test car is a vert and has gone 10.93 with no nos

 

[T3 Cobra]

Originally posted by matt lankford
jdm has tons of parts they dont have on their site, there test car is a vert and has gone 10.93 with no nos

When I spoke to Jim at JDM we spoke for about 30 minutes about wheel hop/tb/exhaust/headers etc etc. What a nice conversation that was. He also mentioned a plug in tuner for the 03 to be out shortly that will not require a chip?

Wish he was closer to me because my 03 would be there for many mods



:beer:

 

[03DOHC]

Originally posted by T3 Cobra
He also mentioned a plug in tuner for the 03 to be out shortly that will not require a chip?

I asked them about that in august. Click me. I hope it's soon.

On topic, I'll be doing the shocks on Sunday. Thanks Larry!:beer:

 

[Robb03]

Please keep me informed about the Amazon racing hop kit. I wanna know how it works on ya'lls cars. I probably will do the stage 2 kit if it is working to solve the problems on here. Thanks everyone

 

[03DOHC]

Originally posted by Robb03
Please keep me informed about the Amazon racing hop kit. I wanna know how it works on ya'lls cars. I probably will do the stage 2 kit if it is working to solve the problems on here. Thanks everyone

Will do. I'll bring my digital camera and take pics as I scrape my hands and bust my knuckles.

 

[ObieFox]

O3DOHC, What is the "NGS" you refer to in your old thread. I have not heard that term before.

Thanks,
Kevin

 

[03DOHC]

Originally posted by ObieFox
O3DOHC, What is the "NGS" you refer to in your old thread. I have not heard that term before.

Thanks,
Kevin

NGS is the New Generation Star Tester. Instead of a small rectangular box with a couple of buttons, the star tester, the NGS is more sophisiticated. It has a BIG knob and a couple of buttons. It allows you to interface with the car's computer.

This is an NGS.

 

[mustangtaz]

IRS Wheel Hop

I posted this on another forum, but it seems appropriate here.

There are three basic IRS systems used in the Cobra Mustang, each with its own set of problems. The 99-01 IRS was designed for a smooth ride and low NVH. To achieve this, soft bushing were used in the subframe and the control arms. Although it is natural for Cobra owners to do burnouts, this series of IRS was never designed to handle this type of use. Ford mandated that the car ride smoothly and so soft springs, dampers and bushings were used. The second type of IRS was installed in the 2000 Cobra R. It had very high durameter bushings in the control arms as well as a pinion brace, amoung several other durability and road racing modifications. Additionally, it was equipped with 750 lb/in springs and road racing valved shocks. Although a significant improvement over the "smooth ride" version that was in the 99-01 Cobras, it was not intended to be used for drag racing. The latest rendition found in the 03 Cobra was designed with handling in mind. The control arm bushing are higher durameter than the previous Cobras, although less than the Cobra R. The 600 lb/in springs and semi road racing valving do not make for great drag racing launches. Given the basic designs of these, depending on which version you have, there are a few things that can be done to improve the function of the IRS and eliminate the wheel hop.

First, if your Cobra does not have the pinion brace, add it. Although Paul's is a good unit, the Ford piece fits perfectly and is both cheap and strong. I would recommend the harder Maximum Motorsports or Steeda bushings. Second, replace the front IRS subframe bushings with a polyurethane or Delron material and a steel sleeve. Do not replace the rear bushings unless the car is a track car only. NVH and high speed gear noise will increase significantly when the rear subframe bushings are replaced. These bushings are the same as the pre '94 Mustang trailing arms, so if you have a set of the Energy Suspensions items, use them. When you replace these bushings, replace the mounting bolts with standard 14 mm bolts instead of the stepped 12 mm pieces. The stock 12 mm bolts allow the subframe to move and should be replaced.

If your car has a 99-01 IRS, you will need to upgrade the control arm bushings, as the stock units are very soft. If your car is a street car where listening to tunes is important, install the 03 Cobra pieces, else, install Delron with the metal sleeve. Also, the knuckles (uprights) are much stronger on the 03 unit. You will need a VIN number from a Cobra R to get the R units and a VIN number from an 03 Cobra to purchase the 03 control arms.

Next, fabricate a bracket from 3/16" x 4"x 4" Flat ASTM A108 steel that will be welded to the outside edge of the rear subframe mount bracket and extended up inside the wheel well to a point approximately 1.5" above the level of the trunk floor. Drill two 3/8" holes through the bracket and wheel well into the trunk area, approximately 0.75" above the trunk floor. Install grade 8 bolts, nylon insert nuts and W series, type B, washers. You will have to massage the plate to conform to the wheel well. This modification is very important to the elimination of wheel hop. The cantilever bracket that mounts the IRS subframe to the frame bends considerably under heavy throttle or cornering loads. Additionally, you should replace the shocks with AFCO 7" stroke, double-adjust stock car shocks. This will require the fabrication of a small bracket for the upper mount. These shocks are inexpensive and provide excellent frequency control. Finally, be sure to check the pinion nut and all the center section mounting bolts. These have been known to be loose with little or no mileage on the car.

One of the side benefits to these modifications is a significant improvement in steering compliance. The car actually becomes pretty neutral and the off-center compliance is much quicker. If cornering is important to you, slot the upper control arm mounts for the uprights approximately 3 mm inboard. Modify the cam bolts to allow negative camber settings. You should see approximately 1.2 - 1.3 degrees of negative camber with this modification, and a noticable improvement in corner transition.

William

 

[2F2F]

> I posted this on another forum, but it seems appropriate here.

I reposted your comments in this forum here: <http://www.svtperformance.com/forums/showthread.php?s=&threadid=26827&>. Excuse me for not giving you credit.

Mathis, William R. Mustang Performance Handbook: Engine and Drivetrain Modifications for Street, Drag Strip or Road Racing Use. H.P. Books, 1994.

 

[2F2F]

> ...if your Cobra does not have the pinion brace...

Does the pinion brace refer to the originally-equipped cross member #4?

> I would recommend the harder Maximum Motorsports...[pinion brace] bushings.

Just ask MM for their IRS pinion brace bushings I presume.

>...replace the front IRS subframe bushings...

MM mentioned that they did not have front IRS subframe bushings. Is there another way to refer to these bushings?

> ...rear subframe bushings...

MM mentioned that they did not have rear subframe bushings available for the '03. Should I be referring to the bushings for "the pre '94 Mustang trailing arms" instead?