Need help with wheel hop

DrRobert · 02-15-2015, 11:12 PM

I modded my suspension to my satisfaction before touching the engine. Got a custom remote tune from PTF and all was well. Added a new ER FMIC and CP and then the car developed wheel hop. By that I mean that with hard launches for 0-60 or 1/4 mile runs, or with hard acceleration from low-moderate speed, the rear wheels lose grip and hop sideways once or twice before planting and accelerating. Last week I added the Pure stage 1 turbo and am currently working with PTF on retuning.

Here is my suspension/drivetrain:
335i N55 sport package 6AT
Michelin PSS 225 front/255 rear on stock 18" rims
BMWPS springs and bumpstops
Koni Yellows
Dinan rear upper shock mounts
E93 M3 front sway bar
M3 front control arms, rear guide rods and wishbones, subframe bushings
Quaife LSD

So I hear the Defiv diff lockdown kit solves wheel hop but causes an audible whine that I think I'd probably find annoying. One guy installed delrin diff bushings and got the whine but still had wheel hop. Any other fixes for this? This car is my DD and I really don't want to increase NVH. I'm considering switching to stickier tires, however I still have lots of miles left on the PSSs so would not want to do that unless I was reasonably sure it would solve the problem.

Thanks,
Robert

chris82 · 02-16-2015, 08:21 AM

Quote:

Originally Posted by DrRobert

I modded my suspension to my satisfaction before touching the engine. Got a custom remote tune from PTF and all was well. Added a new ER FMIC and CP and then the car developed wheel hop. By that I mean that with hard launches for 0-60 or 1/4 mile runs, or with hard acceleration from low-moderate speed, the rear wheels lose grip and hop sideways once or twice before planting and accelerating. Last week I added the Pure stage 1 turbo and am currently working with PTF on retuning.

Here is my suspension/drivetrain:
335i N55 sport package 6AT
Michelin PSS 225 front/255 rear on stock 18" rims
BMWPS springs and bumpstops
Koni Yellows
Dinan rear upper shock mounts
E93 M3 front sway bar
M3 front control arms, rear guide rods and wishbones, subframe bushings
Quaife LSD

So I hear the Defiv diff lockdown kit solves wheel hop but causes an audible whine that I think I'd probably find annoying. One guy installed delrin diff bushings and got the whine but still had wheel hop. Any other fixes for this? This car is my DD and I really don't want to increase NVH. I'm considering switching to stickier tires, however I still have lots of miles left on the PSSs so would not want to do that unless I was reasonably sure it would solve the problem.

Thanks,
Robert

You mean it's hopping when it goes over a bump? Looks like you have all the good stuff that normally solves the wheel hop issue. Depending on the power you're putting down, you might want to research the solid aluminum subframe bushings.

DrRobert · 02-16-2015, 09:33 AM

No, it is hopping on a perfectly smooth road on hard launch or large, rapid acceleration like when passing.

Blaster400 · 02-16-2015, 09:56 AM

You need a differential lockdown kit. That will solve your wheel hop problem.

Blaster400 · 02-16-2015, 10:00 AM

I have a Quaife and DEFIV lockdown kit with minimal NVH. Totally solved my wheel hop issue. Here is another choice that is cheaper. http://***********ions.com/products/...e-for-e9x-335i

AndrewLakes · 02-16-2015, 11:51 AM

Reduce your rear shock rebound damping?

DrRobert · 02-16-2015, 11:54 AM

Quote:

Originally Posted by AndrewV

Reduce your rear shock rebound damping?

Yeah, I was wondering about that. Currently the Konis are set at 3/4 turn from soft in the rear and 1-1/4 turns in front.

AndrewLakes · 02-16-2015, 12:04 PM

Quote:

Originally Posted by DrRobert

Yeah, I was wondering about that. Currently the Konis are set at 3/4 turn from soft in the rear and 1-1/4 turns in front.

Huh, I have mine at 2 turns from soft in the rear (3 turns total IIRC to get to max) and 1.75/3 in front. But, no LSD for me.

Maybe increase rebound then? It seems to me that too little rebound is just as bad as too much for max grip. I think it's typical to have more shock damping in the rear than the front for these cars.

raceyBMW · 02-16-2015, 12:28 PM

Adjusting damping rate might help, but you will still likely need the lockdown kit. I also get wheel hop on a hard launch with sticky tires, but haven't done the lockdown yet.

DrRobert · 02-16-2015, 12:35 PM

What about replacing the toe arms - would that help? I have the stock ones still.

Blaster400 · 02-16-2015, 12:53 PM

Quote:

Originally Posted by DrRobert

What about replacing the toe arms - would that help?

No.

DrRobert · 02-16-2015, 01:25 PM

Quote:

Originally Posted by Blaster400

No.

Can you elaborate why you think they would not help? I thought it was excessive toe in on hard acceleration that causes the deflection in the suspension that results in wheel hop. Wouldn't controlling toe better help limit that deflection and decrease wheel hop?

DrRobert · 02-16-2015, 03:34 PM

So far I've talked to two different well-respected indy shops and posted in two different forums on this message board about this problem, and have been advised to:
- get new tires
- get new toe arms
- get new differential bushings
- lock down the diff
- adjust rear shocks

Will probably start with adjusting the shocks since that is cheap, but if that doesn't fix it I'm not clear on what to try next.

DrRobert · 02-16-2015, 03:35 PM

Quote:

Originally Posted by raceyBMW

Adjusting damping rate might help, but you will still likely need the lockdown kit. I also get wheel hop on a hard launch with sticky tires, but haven't done the lockdown yet.

What mods do you have?

AndrewLakes · 02-16-2015, 04:03 PM

Quote:

Originally Posted by DrRobert

So far I've talked to two different well-respected indy shops and posted in two different forums on this message board about this problem, and have been advised to:
- get new tires
- get new toe arms
- get new differential bushings
- lock down the diff
- adjust rear shocks

Will probably start with adjusting the shocks since that is cheap, but if that doesn't fix it I'm not clear on what to try next.

You say the wheels hop sideways - is it always in one direction or both? (How is your rear alignment?)

DrRobert · 02-16-2015, 04:57 PM

Quote:

Originally Posted by AndrewV

You say the wheels hop sideways - is it always in one direction or both? (How is your rear alignment?)

Good question. I think it has only hopped to the left.

Here is my alignment from last Sept after I had the Konis installed, I don't think I've checked it since then. Should I?

AndrewLakes · 02-16-2015, 05:14 PM

Quote:

Originally Posted by DrRobert

Good question. I think it has only hopped to the left.

Here is my alignment from last Sept after I had the Konis installed, I don't think I've checked it since then. Should I?

The numbers they set to look good. I'd only check the alignment again if you did a suspension job on the rear, you HPDE, or hit lots of potholes.

DrRobert · 02-16-2015, 05:36 PM

Quote:

Originally Posted by AndrewV

The numbers they set to look good. I'd only check the alignment again if you did a suspension job on the rear, you HPDE, or hit lots of potholes.

Nope, none of the above since then. Thanks!

vwetish · 02-18-2015, 05:26 PM

Quote:

Originally Posted by DrRobert

Nope, none of the above since then. Thanks!

I can help offer you this unit. PM if interested

DrRobert · 02-18-2015, 06:09 PM

Is that the defiv lockdown kit?

vwetish · 02-18-2015, 06:34 PM

Quote:

Originally Posted by DrRobert

Is that the defiv lockdown kit?

No, it isn't.

DrRobert · 02-19-2015, 12:23 AM

Quote:

Originally Posted by vwetish

No, it isn't.

What is it then???

02-15-2015, 11:12 PM	#1
DrRobert Normal Person 147 Rep 862 Posts Drives: 2011 E90 335i Join Date: May 2014 Location: paradise iTrader: (0) Garage List 2011 E90 335i [0.00]	Need help with wheel hop I modded my suspension to my satisfaction before touching the engine. Got a custom remote tune from PTF and all was well. Added a new ER FMIC and CP and then the car developed wheel hop. By that I mean that with hard launches for 0-60 or 1/4 mile runs, or with hard acceleration from low-moderate speed, the rear wheels lose grip and hop sideways once or twice before planting and accelerating. Last week I added the Pure stage 1 turbo and am currently working with PTF on retuning. Here is my suspension/drivetrain: 335i N55 sport package 6AT Michelin PSS 225 front/255 rear on stock 18" rims BMWPS springs and bumpstops Koni Yellows Dinan rear upper shock mounts E93 M3 front sway bar M3 front control arms, rear guide rods and wishbones, subframe bushings Quaife LSD So I hear the Defiv diff lockdown kit solves wheel hop but causes an audible whine that I think I'd probably find annoying. One guy installed delrin diff bushings and got the whine but still had wheel hop. Any other fixes for this? This car is my DD and I really don't want to increase NVH. I'm considering switching to stickier tires, however I still have lots of miles left on the PSSs so would not want to do that unless I was reasonably sure it would solve the problem. Thanks, Robert
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02-16-2015, 09:33 AM	#3
DrRobert Normal Person 147 Rep 862 Posts Drives: 2011 E90 335i Join Date: May 2014 Location: paradise iTrader: (0) Garage List 2011 E90 335i [0.00]	No, it is hopping on a perfectly smooth road on hard launch or large, rapid acceleration like when passing.
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02-16-2015, 09:56 AM	#4
Blaster400 Captain 127 Rep 865 Posts Drives: BMW X3 35i, Porsche Macan S Join Date: Jul 2012 Location: Scottsdale AZ iTrader: (3) Garage List 2018 Porsche Macan S [0.00] 2012 BMW X3 35i [0.00]	You need a differential lockdown kit. That will solve your wheel hop problem. __________________ MOTIV 750 ST \| MOTIV PI \| 100% E85 \| Fuel-it Stage 4 LPFP \| MOTIV Boost Box + MHD Protune \| Quaife \| Öhlins \| Brembo \| Akrapovic
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02-16-2015, 10:00 AM	#5
Blaster400 Captain 127 Rep 865 Posts Drives: BMW X3 35i, Porsche Macan S Join Date: Jul 2012 Location: Scottsdale AZ iTrader: (3) Garage List 2018 Porsche Macan S [0.00] 2012 BMW X3 35i [0.00]	I have a Quaife and DEFIV lockdown kit with minimal NVH. Totally solved my wheel hop issue. Here is another choice that is cheaper. http://***********ions.com/products/...e-for-e9x-335i __________________ MOTIV 750 ST \| MOTIV PI \| 100% E85 \| Fuel-it Stage 4 LPFP \| MOTIV Boost Box + MHD Protune \| Quaife \| Öhlins \| Brembo \| Akrapovic
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02-16-2015, 11:51 AM	#6
AndrewLakes Custom User Title 16 Rep 131 Posts Drives: E90 335i Join Date: Jan 2014 Location: Alameda, CA iTrader: (0)	Reduce your rear shock rebound damping?
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02-16-2015, 12:28 PM	#9
raceyBMW king of the hills 92 Rep 2,915 Posts Drives: 2011 M3 w/ESS55, 2001 540i/6 Join Date: Dec 2006 Location: Arvada, CO iTrader: (1) Garage List 2001 BMW 540i/6 [8.17] 1994 530i [9.00] 2007 335i Coupe [8.37]	Adjusting damping rate might help, but you will still likely need the lockdown kit. I also get wheel hop on a hard launch with sticky tires, but haven't done the lockdown yet.
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02-16-2015, 12:35 PM	#10
DrRobert Normal Person 147 Rep 862 Posts Drives: 2011 E90 335i Join Date: May 2014 Location: paradise iTrader: (0) Garage List 2011 E90 335i [0.00]	What about replacing the toe arms - would that help? I have the stock ones still.
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02-16-2015, 03:34 PM	#13
DrRobert Normal Person 147 Rep 862 Posts Drives: 2011 E90 335i Join Date: May 2014 Location: paradise iTrader: (0) Garage List 2011 E90 335i [0.00]	So far I've talked to two different well-respected indy shops and posted in two different forums on this message board about this problem, and have been advised to: - get new tires - get new toe arms - get new differential bushings - lock down the diff - adjust rear shocks Will probably start with adjusting the shocks since that is cheap, but if that doesn't fix it I'm not clear on what to try next.
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02-18-2015, 06:09 PM	#20
DrRobert Normal Person 147 Rep 862 Posts Drives: 2011 E90 335i Join Date: May 2014 Location: paradise iTrader: (0) Garage List 2011 E90 335i [0.00]	Is that the defiv lockdown kit?
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