[doughboy]

In my experience, wheel hop is when you are only just breaking traction -i.e not giving it enough beans to really overwhelm the grip and snap the wheels round quickly.

As described, due to flexing & oscillations in the drive and suspension this allows the tyre to grip/slip/grip/slip at quite a low frequency giving the unpleasant bounce/hop etc.

If you want to spin up smoothly then give it more gas & more aggressive clutch engagement to swiftly break traction and get a higher tyre-to-tarmac spin speed which will prevent "re-grip" and hop.

Give it more welly in other words... it is kinder to your car than stressful wheel hop.

[3tekcorps]

Originally Posted by doughboy

In my experience, wheel hop is when you are only just breaking traction -i.e not giving it enough beans to really overwhelm the grip and snap the wheels round quickly.

As described, due to flexing & oscillations in the drive and suspension this allows the tyre to grip/slip/grip/slip at quite a low frequency giving the unpleasant bounce/hop etc.

If you want to spin up smoothly then give it more gas & more aggressive clutch engagement to swiftly break traction and get a higher tyre-to-tarmac spin speed which will prevent "re-grip" and hop.

Give it more welly in other words... it is kinder to your car than stressful wheel hop.

I was wondering if that was part of it. I was barely out of break-in and still not feeling like I should flog the car. Now I feel like I should save the tires a bit.

Adulting is so boring sometimes.

[Proctor750]

Good news. Someone else noticed this shortcoming:

[Poochie]

Originally Posted by Proctor750

Good news. Someone else noticed this shortcoming:

Nice find!!!

[Proctor750]

Originally Posted by Poochie

Nice find!!!

My buddy from Zakspeed found them - He does a lot of custom fab and track prep for BMW's (used to crew with bimmerworld). Always finds stuff like this or makes it. He is in Louisville, KY.

I will definitely get them

[Poochie]

Originally Posted by Proctor750

My buddy from Zakspeed found them - He does a lot of custom fab and track prep for BMW's (used to crew with bimmerworld). Always finds stuff like this or makes it. He is in Louisville, KY.

I will definitely get them

That's impressive that some folks can reverse-engineer a vehicle down to its frame and improve upon on it..

Did he say if it made a discernible improvement to the wheel hop issue ?

[Commanderwiggin]

Link to company?

And how did this improve the dynamics?

[Proctor750]

Originally Posted by Poochie

That's impressive that some folks can reverse-engineer a vehicle down to its frame and improve upon on it..

Did he say if it made a discernible improvement to the wheel hop issue ?

Not sure - I haven't ordered it yet and he only recently stumbled on it when we were thinking of a solution.

You should see some of the tricks we did with the E30 subframe

Originally Posted by Commanderwiggin

Link to company?

And how did this improve the dynamics?

https://www.kmpdrivetrain.com/produc...4-bushing-set/


There is the bushing set for the front bracket and then a rear machined piece which attaches to the diff cover and allows for a second mount.

Any high HP or track driven car should have a twin mounting for the differential. The solid bushings help with flex. Ideally you only want your tires to have the ability to flex, everything else messes with geometry let alone breaking something. With the diff It's more to help keep everything solid but won't net you anything with geometry- read about the single ear diff mounts of yesteryear...

[Proctor750]

Got rid of the giant rubber thrust arm bushings. Front feels nice. Had to swap hardware out - not sure why it came with stainless for an aluminum part...

Also: Check out the bottom of the caliper

Gave the Porsche ducts a shot, 4 bucks a pop and they clipped right in after trimming a tab. No clue if it will help with anything.

[doughboy]

Nice, is the new bushing an off-the-shelf part or did you have it made up for you?

[Proctor750]

Originally Posted by doughboy

Nice, is the new bushing an off-the-shelf part or did you have it made up for you?

There are several offerings out there, I think synchro driveworks was one of the first to do these style awhile ago.
This one is from bimmerworld and is isolated OEM style. Should outlast the OE rubber many times over. The front feels a bit nicer on the road as well.

[Pete H]

Hmmm...little brakes and better pads for me I think. How many miles did it take to pick up those score marks on the caliper?

[Proctor750]

Originally Posted by Pete H

Hmmm...little brakes and better pads for me I think. How many miles did it take to pick up those score marks on the caliper?

Hard to say as I had 1200 on it in europe before getting to take a wheel off back here in the states. It was there the first time I looked so at most 1200 miles. It has close to 5k on it now.

[Pete H]

Thanks for the info, following the AP big brake threads with interest, that really is running very tight.

[Diogo AMS]

i have zero wheel hop, did all the diff bushings, rear arms and a good alignment

[Proctor750]

I also unplugged the little exhaust valve connectors. Wrapped them in a little glove finger then zipped them up to the nearest loom (finger opening facing down).

[doughboy]

Won't that make the valves stay always shut?

[Proctor750]

Originally Posted by doughboy

Won't that make the valves stay always shut?

I believe the actuation is shut under power. Based on how it sounds they are wide open. Probably have a soft code but who cares. It's still louder on start up but I believe that is just mapping since there is nothing connected to either valve now.

[DriverDaily]

Originally Posted by Poochie

The missing part is a vibration damper.. I guess they assume the hard-core M2C didn't need it or maybe they're just being cheap.. :

It does look like you can purchase another one and just add it, if you please..

Does anyone have the part number for this "Vibration Damper"? It doesn't seem to be in RealOEM

I'd like to combine OEM polyurethane bushings with Turner's dual rear diff mount and these vibration dampers.

[doughboy]

Originally Posted by Proctor750

I believe the actuation is shut under power. Based on how it sounds they are wide open. Probably have a soft code but who cares. It's still louder on start up but I believe that is just mapping since there is nothing connected to either valve now.

....thread resurrection...

The valves are powered into either position and stay there. So you need to remove power when the valves are in the position you require.

Better to remove the valve motor fuses in the trunk, no error code and no messing about under the car. Open the valves then remove the fuses, they stay open forever.

[doughboy]

Originally Posted by DriverDaily

Does anyone have the part number for this "Vibration Damper"? It doesn't seem to be in RealOEM

I'd like to combine OEM polyurethane bushings with Turner's dual rear diff mount and these vibration dampers.

I think that kind of small mass vibration damper is more for higher frequency vibrations / NVH than very low frequency more violent transmission hops.

I've noticed when hooning out of junctions etc and sliding / spinning the wheels that they only "hop" when driving with MDM on (no spin at all with MDM off). If you switch DTC OFF completely it just spins smoothly to the limiter, smoke aplenty.

I think the MDM mode is cutting throttle / power (as it is meant to do to keep things in trim) and this means the tyres start to judder / hop as they partially grip. This seems to make sense, if you do it with MDM on in low grip situations (wet, dusty) it spins just fine.

Guaranteed the smooth spinning, smoke billowing, opposite lock slides you see online are with DTC fully off always.

[richard in NC]

Originally Posted by doughboy

I think the MDM mode is cutting throttle / power (as it is meant to do to keep things in trim) and this means the tyres start to judder / hop as they partially grip. This seems to make sense, if you do it with MDM on in low grip situations (wet, dusty) it spins just fine.

Guaranteed the smooth spinning, smoke billowing, opposite lock slides you see online are with DTC fully off always.

I agree with this. I've experienced the shutter/wheel hop rarely but I believe only in MDM mode. Always moderately hard 1st gear launches (I have the M-DCT). I just played all day on a skid pad, intending for full DSC off. I was occasionally in MDM mode, mostly unintentionally and I believe that's when I experience the wheel hop, but it felt like a jerky throttle, exactly as if the computer was cutting power intermittently. No vibration damper would solve that.