wheel hop

[little blackie]

what's up brothers and sisters - got a 22 "little blackie" -Tuned with intercooler and borla s type cat back - it's rad, but on occasion, I'm getting nasty wheel hop at the end of 1st gear. Anyone else?? Anyone have this with stock suspension but not with lowering springs? I'm contemplating installing the steeda springs and hoping this might help???? Any info is much appreciated

 

[TMac]

I hate to tell you this, but... You are in for some big problems with a single-bolt rear diff. The source of wheel hop is deflection of bushings throughout the suspension due to the windup of the rear differential under torque. This causes the tires to gain traction, lose traction, etc. That oscillation will lead to really, really bad things. Springs won't help, shocks won't help. If this has happened multiple times, I'd check into removing the rear diff bolt (horizontal from the subframe into the diff cover) and see if it's bent. If it's not, it soon will be.

 

[little blackie]

it has 2 bolts

 

[TMac]

You're lucky with the 2 bolt. However, that doesn't address the fact that there is enough deflection overall to give you wheel hop. And that's what you have to address.

You might have the only "unicorn" two bolt 2022 in history.

 

[F=MA]

https://fenfabrication.com/shop/explorer-st/fenfabrication-explorer-st-2020-hp-rear-toe-link/

 

[l1tech]

I hate to tell you this, but... You are in for some big problems with a single-bolt rear diff. The source of wheel hop is deflection of bushings throughout the suspension due to the windup of the rear differential under torque. This causes the tires to gain traction, lose traction, etc. That oscillation will lead to really, really bad things. Springs won't help, shocks won't help. If this has happened multiple times, I'd check into removing the rear diff bolt (horizontal from the subframe into the diff cover) and see if it's bent. If it's not, it soon will be.

While I agree with you on the 1 bolt issue I have to respectfully disagree with you on the cure. Springs and or shocks will most definitely help or cure this issue. While soft bushings can contribute to the wheel hop issue the main cause is poor control of the suspension which is a direct result of shock dampening and or spring rate. I have had multiple high and low horsepower vehicles both on and off road over the years that have had wheel hop and all were cured with proper springs and or shocks. If you can keep the tires on the ground wheel hop will be eliminated. We all know that the springs main purpose is to hold the vehicle up but it also plays a part in forcing the tires down to the ground. We also know that the main function of the shock is to control the rebound and compression of the spring. If you can tune those two things together you eliminate wheel hop. I once had an old 1983 Toyota truck that I built into an offroad vehicle. I removed the bed and built a flat bed for it because it was rusted beyond belief. After installing a 5 speed and a few modifications to the 22r that was under the hood the back end would hop horribly on pavement and while rock climbing if you lost traction. Nothing more than a custom set of springs completely cured that issue. My 68 Camaro also had this issue, not rock climbing obviously, after the 327 in it gained some respectable hp upgrades, nothing like a good mouse motor turning 7k, anyway.....after respringing the rear end it was able to put the power to the ground without issue. Same thing applies to my Can Am X3 and once again springs in conjunction with shock valving cured that 100%.

 

[TMac]

I get what you're trying to say, but "forcing the tires down to the ground" is not valid. There is the same amount of mass regardless of the spring rate. As far as "...the main cause is poor control of the suspension..." I completely agree, but you compare totally different vehicles as arguments.

There is a potential that springs and/or shocks can change the "attenuation" of the the oscillation. All that does is to change the frequency of the wheel hop, which may in fact apparently cure the issue under certain situations. It does not change the windup of the differential and other component deflection unless you're talking about solid axle leaf-spring cars like the 68 camaro, or the toyota you mentioned.

An IRS car with coil springs, like the ST, is an entirely different animal.

 

[blackdog]

I hate to tell you this, but... You are in for some big problems with a single-bolt rear diff. The source of wheel hop is deflection of bushings throughout the suspension due to the windup of the rear differential under torque. This causes the tires to gain traction, lose traction, etc. That oscillation will lead to really, really bad things. Springs won't help, shocks won't help. If this has happened multiple times, I'd check into removing the rear diff bolt (horizontal from the subframe into the diff cover) and see if it's bent. If it's not, it soon will be.

This right here, and nice simplified post TMAC. I have been working on and driving fast cars since the 60's, and wheel hop was a problem then, and it's a problem now. Simply stated wheel hop is caused by torsion to the rear axle. More grip and horsepower equals more wheel hop as the rear axle winds up and then releases due to INTERMITTENT traction. In my day most cars, if not all cars had horsepower to spare and tires that smoked. That's not the case today as traction is tamed. Ladder braces fixed the hop back then and I imagine there's a solution for the ST that stops the axle twisting. And remember that wheel hop is lost traction (wheels off ground, and higher ETs.

Wheel Hop - Causes, Effects and Cures - NASA Speed News Magazine

 

[bigcat1185]

Traction bars

 

[butt_yodel]

I hate to tell you this, but... You are in for some big problems with a single-bolt rear diff. The source of wheel hop is deflection of bushings throughout the suspension due to the windup of the rear differential under torque. This causes the tires to gain traction, lose traction, etc. That oscillation will lead to really, really bad things. Springs won't help, shocks won't help. If this has happened multiple times, I'd check into removing the rear diff bolt (horizontal from the subframe into the diff cover) and see if it's bent. If it's not, it soon will be.

My 1-bolt wheel hops a bunch. Have had an AWR brace on it since going to 93 E30 tune, might get this inspected next time I'm at the dealer. Think that brace does much to stop it from bending? I recall this being a highly debated topic.

 

[butt_yodel]

Saw these in the Facebook group this morning:

https://fenfabrication.com/shop/exp...B-Ig1oJQ8Xw1DmvewU3IOyyEbBFYT7wcjfvpMnkIBEVjw


May not be bad to try out.

 

[blackdog]

Traction bars

There are no leaf springs in this truck. Watch the video in the link I posted.

 

[UNBROKEN]

Traction bars

IRS

 

[blackdog]

what the hell is IRS?

 

[Cajun Heat]

what the hell is IRS?

Independent Rear Suspension.

 

[blackdog]

I thought so, but the acronyms used in some cases could mean anything.

I have sent a letter to BMS requesting information concerning wheel hop and the possibility they may have products in work or available for the ST. BMR is the finest suspension component company on the planet. The very reason untold numbers of pro drag racers and NASCAR drivers use their products.

BMR Suspension - Performance Suspension & Chassis Parts

 

[Cajun Heat]

I did too and below is their response.

We do not have plans for explorer parts at this time.



Thanks,

Glenn Cox

Late model specialist


P: 813.986.9302

F: 813.986.8055

 

[UNBROKEN]

The ID Speed diff brace and FenFab toe links will cure the hop. I used to be able to make mine shake the tires at will…now I can’t.

 

[butt_yodel]

The ID Speed diff brace and FenFab toe links will cure the hop. I used to be able to make mine shake the tires at will…now I can’t.

Ordered some of Brett's toe links. Any alignment needed after pulling out the OEM? I got alignment done recently for my H&Rs.

 

[UNBROKEN]

Ordered some of Brett's toe links. Any alignment needed after pulling out the OEM? I got alignment done recently for my H&Rs.

All I did was leave the weight on the car…backed up onto ramps. Scribed the eccentric and frame so I could put it back how it was then swapped the links and lined the scribe marks back up. Zero issues…the finer the scribe mark the more accurate you’ll be.