ford4v429

A few weeks ago, took off one night and stepped on it a bitin first- car shuddered hard like wheelhop/but seemed faster...after getting home, happened to think'did you turn TCS off?'... well tonight roads were a bit wet, TCS was off and taking off it slipped a little bit- same shudder.

Now I'm wondering is it wheel hop? is it just the pirellis?

I noticed something else the other night when underneath- rt rear spring pad is pinched under the coil spring- thought 'i better fix that', but then it will likely need replaced as its crushed pretty bad- I wonder if spring offcenter of axle might cause some bushing compression contributing to wheelhop? heres a pic of the spring pad- might want to look at yours too...

anyone else out there getting 'wheelhop like' shudder? any suggestions? (will reseat the spring this weekend, gonna send the pic of that and my seamsealer gaps to ford along with the survey)

eighty6gt

Wet roads exasterbate wheelhop, and these cars are certainly subject to it.

I'm going to try and adress it with a set of LCA's. These have the johnny joint style bushings that may or may not adress the "tearing" problem people are having with control arms. I'll keep an eye on 'em.

http://www.hotpart.com/index.php?p=show&id=130

biznazion

Maybe it's my perception, but I think you can see some wheel hop in the latest running mustang commercial...

cop on my back

Huge problem with this car, you are not alone. It is very bad on wet roads, unless you really spin the crap out of the tires and then it subsides.

I am also getting some LCA's to try to help with this, but some here still have it with them installed.

Do a search on this, there has been a lot of talk about it.

nonsensez9

LCA's helped only a little on my car. trying an upper 3rd link in the spring. should'a gone that route to begin with, it's cheaper.

169stang

I have a Steeda upper third link and LCA's on ebay right now!
http://motors.search.ebay.com/_W0QQsassZ169stang

ford4v429

My 69 had severe wheelhop- I put a set of lakewood slapper bars on it, and it took care of it...maybe I'll find/fab some similar for the new one- maybe get them chromed and put some lakewood stickers on them so they'll match the 69

I think they look cool, and certainly prevent windup...without the harsh ride of urethane bushings...the bushings are such a close radius from axle centerline(compared to slapper snubber at the front control arm point) they'd need to be AWFULLY hard to compare to a set of bars 20" long...I just wanted to confirm it was wheelhop, as my older cars seemed to hop at a much lower frequency than this one...old mustang/camaro, severe, but only couple times a second, new mustang probably 5-10 hz...not as severe, but sure hard on the chassis.

Import-Slaya

The BMR nonadjustable (poly/poly bushings) LCA's cured it for me. A lot has to do with launch style I think. I tend to slip the clutch a lot and never had a bad problem, so the LCA's cleared it up 100% for me.

Do a search and you'll see others have had mixed results with the LCA's and needed the UCA to cure it. Keep in mind that a UCA without a pivot point (like the Metco) will hurt your handling as it will limit rear axle articulation. Not an issue for the drag strip, but definitely an issue elsewhere if you push it.

Fazm

I also noticed the wheel hop in the new mustang commercial. Thought they would have edited that out or something. Maybe most people dont notice.

169stang

I'm sure they know about it by now. I'm sure all the buzz has gotten back to someone.

ford4v429

questions...I saw the pivoting upper arm, but had to wonder...if upper arm is at an angle when axle tilts, shouldnt lower arms also???the stock lower arms appear flat, so would guess they twist to allow if rubber not enough, but the aftermarket tubulars ought to pinch lower arm bushings too wouldnt they?

RPM

After lowering my '06 I noticed wheel hop went away! I thought this strange 'cause most post that AFTER lowering is when they noticed wheel hop starting or getting worse. The real fix to to relocate instant center further forward.

nonsensez9

newb question... what is instant center and how does moving it forward help eliminate wheel hop? thanks.

169stang

First of all, wheel hop is due to the flexibility of the 3 pt. control arms-2 lower, 1 upper.
Ideally, you want your driveline perfectly straight when you stomp on the gas. When you get on the gas, the pinion/differential torque upwards. Tires rolling forward, the pinion (front of the differential where the driveshaft connects) turns upward. You want the pinion angle to be at 0 degrees when you launch. Sitting at a stand still, the pinion angle for the S197 is ideally -3 degrees. So...the pinion travels 3 degrees at launch. If the driveline isn't at 0 degrees at a launch, there's loss of power being put to the tires. Picture how much easier it is to turn a bolt with just a ratchet and a straight socket vs. a ratchet and a socket on a universal socket adapter torquing at an angle. It's easier with the straight socket.
Instant Center: The instant center is a virtual intersecting point of suspension links, including the angle of the control arms and the centerline of the contact patch.

SoFlaBoss

Ditto. However, the average viewer/consumer would never pick up on something like "wheel hop". Anyways, it just adds more action, which is what they want to depict.

stkdidy

no wheel hop here! BMR LCAs ftw

Import-Slaya

Correct. I think the degree of "binding" from the LCA's is fairly negligible, though. In effect it probably has a slight increase in the rear axle effective spring rate--not that it changes the actual springs, but the slight extra force required to compress/twist the poly bushings takes a little more effort.

My driving impressions from the poly/poly arms (other than fixing the wheel hop issue) are (1) the back end doesn't waggle as much in hard corners; and (2) there is slightly less understeer--this I attribute to probably effective increase in rear axle spring rate. In sum, only positive effects in both straight line launches and in the twisties. Right now I don't see a need to go to the spherical bearing ends.

I'll probably stick with the stock UCA for now until there is more feedback from the Metco version, or MaximumMotorsports releases their suspension parts for the S197.