Z4M suspension options that are NOT KW V3

[maupineda]

Originally Posted by grannyknot

I admittedly don't know a lot about suspension but I'm looking for something better than stock but still not too harsh, is that possible?
What do you guys think about the H&R setup that Turnermotorsport sells?
https://www.turnermotorsport.com/p-1...er-suspension/

H&R are valved very aggressively, plus the rates are also hi, they are very harsh out of the box. What makes them harsh is the gas pressure which is too high 40-60 pounds. So you need more than that to initiate damper travel and that is what translate to jittery motions.

[grannyknot]

Originally Posted by maupineda

H&R are valved very aggressively, plus the rates are also hi, they are very harsh out of the box. What makes them harsh is the gas pressure which is too high 40-60 pounds. So you need more than that to initiate damper travel and that is what translate to jittery motions.

Thanks, I talked to Turner and they said the progressive springs on the H&R kit are 20% firmer than stock.
Is there a way to adjust or modify the pressure in the shocks for a more compliant ride or can you recommend a different shock that would do the job?

[maupineda]

Originally Posted by grannyknot

Thanks, I talked to Turner and they said the progressive springs on the H&R kit are 20% firmer than stock.
Is there a way to adjust or modify the pressure in the shocks for a more compliant ride or can you recommend a different shock that would do the job?

There is a guy in Cali who does it but charges and arm and leg, I do not know TBH if other shops would do it. Is not rocket science but you need someone whi has a shock dyno and the spares to seal them up.

Btw, they quoted me 3k

[filtercoffee]

Tckline or ground control use Koni yellows which should be less harsh, if you can figure out how to use stock shock mounts I'd imagine that's the best you could do without going to a custom job

[Sergio19]

I believe a lot of the NVH in the front comes from the much stiffer FCAB and strut mounts. The Z4M FCAB is solid rubber vs the very soft oil filled standard bushing.

If you notice the KW V3 uses an E39 strut mount which has the entire spring and strut supported in a rubber bushing, like most other BMW models.

The Z4M and other M cars use a different strut mount style which hard mounts the spring to the chassis on a wide bearing and has minimal rubber in the centre for the shock. This is obviously more durable for heavy track loads but not as comfortable as the standard BMW strut mount style.

[3002 tii]

Originally Posted by filtercoffee

Tckline or ground control use Koni yellows which should be less harsh, if you can figure out how to use stock shock mounts I'd imagine that's the best you could do without going to a custom job

I’ll just add TCK and GC’s kits are both “custom valved” so slightly different from regular Koni Yellows. And in general, my experience has been Koni tend to be more comfortable (both Sport and FSD) while Bilstein (B6/8) were the worst for everyday driving, just really not practical for tri-state roads. And re H&R kits, anyone I know that’s used it never gave it glowing reviews in either the performance or ride quality categories. Progressive springs with no adjustability… it’s basically a cheap solution to get the exact preferred ride height.

It’s too bad Dinan never offered springs. I ran Dinan springs on my 135is with BMW Performance shocks and that was hands down the best street performance setup I owned.

[chris719]

Originally Posted by 3002 tii

I’ll just add TCK and GC’s kits are both “custom valved” so slightly different from regular Koni Yellows. And in general, my experience has been Koni tend to be more comfortable (both Sport and FSD) while Bilstein (B6/8) were the worst for everyday driving, just really not practical for tri-state roads. And re H&R kits, anyone I know that’s used it never gave it glowing reviews in either the performance or ride quality categories. Progressive springs with no adjustability… it’s basically a cheap solution to get the exact preferred ride height.

It’s too bad Dinan never offered springs. I ran Dinan springs on my 135is with BMW Performance shocks and that was hands down the best street performance setup I owned.

Do you really think B6 + stock springs and properly trimmed bump stops will be worse ride quality than stock? I'm kind of torn between this and KW V3, which just keeps getting more and more expensive.

[86Zed]

Originally Posted by chris719

Do you really think B6 + stock springs and properly trimmed bump stops will be worse ride quality than stock? I'm kind of torn between this and KW V3, which just keeps getting more and more expensive.

KW V3 is a great kit but honestly overkill for the average owners goals. Ground control makes a stellar coilover package, or you could simply go OEM plus with a strut/spring/bumpstop combination as suggested. If you don't plan to use the camber, ride height, or other adjustments, why pay for it?

[chris719]

Originally Posted by 86Zed

KW V3 is a great kit but honestly overkill for the average owners goals. Ground control makes a stellar coilover package, or you could simply go OEM plus with a strut/spring/bumpstop combination as suggested. If you don't plan to use the camber, ride height, or other adjustments, why pay for it?

I'm just trying to not end up with terrible ride quality. The GC kit is fine but it's not all that much cheaper than KW V3 with a discount. Also a lot of camber plates tend to be noisy so I was hoping to avoid them since this is a street car for me. I ended up grabbing the B6s and we'll see how it goes. Sucks that they raise the ride height. Unless I go with stock shocks, which I experienced new in 2008, there are compromises for every solution. I thought hard about the stock parts, but despite being comfortable they are kind of unsettled.

[mmm-five]

I know you ruled them out in your original post, but I've had Bilstein B16 PSS10 on for about 10 years and 40,000 road & track miles, and they've been great.

I crank them up for different tracks, and turn them down for road use.

[maupineda]

Originally Posted by chris719

I'm just trying to not end up with terrible ride quality. The GC kit is fine but it's not all that much cheaper than KW V3 with a discount. Also a lot of camber plates tend to be noisy so I was hoping to avoid them since this is a street car for me. I ended up grabbing the B6s and we'll see how it goes. Sucks that they raise the ride height. Unless I go with stock shocks, which I experienced new in 2008, there are compromises for every solution. I thought hard about the stock parts, but despite being comfortable they are kind of unsettled.

They raise it when new, after a while they settle. To put it in perspective I was at 610mm when new, and are now at 600 after 12k miles and 4 years. Is at a point where I can raise it a bit but 600 seems to work fine, i could raise it up to gain 5mm of travel but is splitting hairs.

[chris719]

Originally Posted by maupineda

The front B6 dampers have too long of a bump stop (70mm), the stock is about 44mm. so what I did is that i trimmed it to 40mm. this would retain the suspension travel same as stock, otherwise you would be riding on the bump stop much. That is why some people complain about a bumpy ride. the Bump stop is internal, so you need to open up, take it out, and cut.

Just fyi, I opened a new B6 for Z4M and the bump stop length was about 40-42mm

[maupineda]

They may have changed it. Good to hear. Mine were 60mm. Will post a pic.

[chris719]

Originally Posted by maupineda

They may have changed it. Good to hear. Mine were 60mm. Will post a pic.

Pic attached. It’s compressed very slightly by the calipers and was full of grease but it’s about 41.