2 03 Cobras go down to broken half shafts!

[HIGH ROLLER]

Went to the track yesterday for the Miloc Invitation at Stanton and there was 3 03 Cobras there including myself,most of the day was cold and driving into a strong headwind.For some reason traction was not there today like usual and we all had wheel hop problems on every pass:cuss: I watched the silver 03 car take off and you could see the car hopping badly then his half shaft broke just after the starting line.Then the mineral grey 03 came up later and the same exact problem happened to him! I had severe wheel hop also but short shifted into 2nd immediately just after the 60ft. mark to keep from breaking mine.This is the first i have heard anyone breaking a half shaft on the 03 Cobras. I already have subframes but was thinking about putting the FR500 IRS Brace on with the Steeda IRS Bushings to help control wheel hop my Cobra. Any input on this would be helpful for everyone that has wheelhop problems.

Matt

 

[Steve B]

I believe we already have a brace - similar to the FR500 brace - installed from the factory.

 

[JB]

yes, there's a tubular crossbrace there that's part of the IRS subframe

 

[HIGH ROLLER]

I am aware of the brace for the 03 Cobra,just wondering if the FR500 or the PHP IRS brace might be designed better or stronger.

 

[46stang]

a friend of mine with a z06 was getting alot of wheel hop on his vette so he purchased some et streets. He told me that the softer sidewall on the et streets absorbs more of the imperfections in the track and it eliminated his wheel hop problem! he also said wheel hop is much harder on drivetrain parts then slicks, do to the axle being shocked from the rapid loading/unloading of the tire.
I noticed if the track is half way prepped my car will hardly hop at all,but if it isn't prepped i have gotten some real bad hop! I will be saving up for some slicks and see how that goes!
Leon

 

[JB]

Originally posted by HIGH ROLLER
I am aware of the brace for the 03 Cobra,just wondering if the FR500 or the PHP IRS brace might be designed better or stronger.

yeah, I hear ya...I was just confirming Steve's comment

you guys are really pushing these things with consistent, hard launches and those of us who haven't had the opportunity to start testing the limits of ours cars owe a lot to you all :beer:

I'm wondering if something else will fit with the OEM one?....Paul's doesn't list it on their '03 page. I can't get under my car now to see if ours is welded or bolted in place

edit: its bolted

 

[matt lankford]

PAUL HELPED DESIGN THE ONE THAT CAME OEM

 

[i8u]

Did this happen on the factory tires?

 

[NetworkingGuru]

Guys,

From what I have read and researched in my quest to eliminate my wheel hop, wheel hop is caused by traction, not lack thereof. Apparently, the tires grip, which causes the weight to shift, which causes a change in the geometry. This change causes a windup in the suspension, usually in the "rubber-band-like" stock bushings, which causes the tire to hop. I have read that this is MUCH more damaging to the suspension than any other kind of launch, due to the forces imposed by the IRS repeatedly being shocked into and out of traction. My first mods to combat this problem (unless someone informs me differently) will be to replace the bushings and add lowering springs. The lowering springs supposedly change the geometry allowing less wind up. We shall see....

 

[jtfx6552]

I disagree, good traction, no hop. I have gotten many 1.8X 60 fts with no hop.

On nights when trac prep was bad, had to let out because of hop.

Also the IRS drag strip expert Joe Lynch, says the more traction, the less hop.

JT

 

[03 Red Cobra]

Again, did this happen with the stock street tires?

 

[HIGH ROLLER]

I believe the silver one was on street tires and the mineral grey was using a drag radial.I have to agree with JT when the track is prepped properly wheel hop should be very minimal,and when the track is not prepped as well that is when we will experience more wheel hop.

 

[sn8k]

Originally posted by jtfx6552
Also the IRS drag strip expert Joe Lynch, says the more traction, the less hop.JT

Yes, and he also alludes to the fact that with the IRS, it's not a matter if you'll break the halfshafts - it's a matter of when. I think there is going to be a fair amount of swaps to the 8.8 live axle among the drag racers here.

 

[mds370]

I also got to witness an 03 break a pass side halfshaft at E-town this weekend. He was on drag radials, had mad wheel hop during his burnout. I watched him launch ,heard a bang.He managed to roll out about 30ft before realizing there was a problem.

 

[AV8R]

Try Pauls High Performance IRS Brace

 

[Mac03Cobra]

Bottom line, if you start to get wheel hop, you better get the hell off the gas. It won't get any better by staying in it or adding power. You will break something.

Depending on the RPM I leave the line, I will sometimes get HOP, others times no. But I do know, once it starts hopping, let off the gas and chaulk up a bad run. Save your car.

The hop starts when the tires lose traction, then they get it back quickly. If you torch the tires and get them spinning fast enough, it won't hop even as you start to hook up as long as you have some speed going.

IRS hates to wound up and released quickly. Even a straight axle will hop, but because of the weight of the whole assembly being one piece on both sides, it will tolerate this a little better. Not only is wheel hop hard on half shafts and the rear end, it's murder on transmissions and clutches.

I feel for the folks that broke their shafts. Next time they need to cut their losses and get off the gas.

Slicks help by not losing traction off the line. Try launching at a little less RPM and it will help keep the wheel hop down. I launch at just about 1600 to 1800.

 

[highmiles]

When the halfshaft breaks, does it hurt anything else? I was just wondering if it shoots pieces all over the place and destroys other parts of the car. Does it seize the drivetrain or lock the engine up.

I haven't seen a halfshaft break, so I am not sure what happens.

Are the 03s that broke going be covered under warranty?

Thanks.

 

[COBRA90GT]

Originally posted by Mac03Cobra
Bottom line, if you start to get wheel hop, you better get the hell off the gas. It won't get any better by staying in it or adding power. You will break something.....

....But I do know, once it starts hopping, let off the gas and chaulk up a bad run. Save your car.....

I 2nd that....saving the car is important, unless you have some $$$ to burn on parts...

:beer:

 

[sn8k]

Originally posted by XSTANG
sn8k
How hard is it to make a pic like in your signature?
I would love to do that with mine

Easy - send me a few pics of your car & I'll design you one tomorrow. [email protected]

 

[08snake]

Originally posted by highmiles
Are the 03s that broke going be covered under warranty?

Thanks.

I can't imagine a dealer not knowing your were drag racing if you show up with broken half-shafts.