[AWC-F87]

Hey guys!

So I'm running KW v3s on my 2018 M2.

It's fairly low with -3+ degrees camber in the front. I'm running 18" RIA wheels.

I run the car hard on the track and in the canyons.

Idk why, but it's still rubbing pretty good on all 4 wheel Wells.

Also even with as much camber as I have in the front I corded the out side of a front tire on track this weekend.

To me the front feels too soft. I'm wondering if anyone has replaced the v3 front springs with something from swift?

I also wonder if the bump stop that came with my ground control plates that I did not install could be taller than the kw bump stop and thus prevent bottoming better?

I've messed with clicker settings and it didn't make a difference.

Really kinda at a loss.

I also REALLY don't like how the only way to adjust height is by lessening the spring pre load. This is such a BS design. Height should be set independent from spring preload.

By being stuck to adjusting the height via spring preload I feel like lowering the car makes the shock sit lower in the stroke allowing for even less up travel and ultimately hitting the bump stop sooner.

Thoughts guys?

[FaRKle!]

The KW V3 kit doesn't have particularly stiff springs. The front is 226lbs/in and rear is 685lbs/in. Those numbers are only slightly higher than the stock spring rates (by less than 10%).

You can fit stiffer springs no problem. KW uses 60mm perches, so for the front you can get an OE to 60mm ID spring adapter (like millway makes), and in the rear you can just drop in any 8" long 60mm ID standard coilover spring.

One thing you need to be careful of for the front is making sure you have enough travel before spring bind. On springs <350lbs/in you typically see the springs with the OE top mount ID and then 60mm on bottom. Above that the mfgs usually include standard coilover springs. This is because you need enough stroke/travel to avoid coil bind.

KW does make a stiffer front spring with the same format as your existing spring. It's PN 60210190 and comes from their F83 V3 kit. That spring is 265lbs/in. I'm running those springs on my Fat Cat Motorsports re-worked B14 struts on my F31. With 8" standard coilover springs I could get the spring to fully bind under some sharp and hard hits.

Playing with your damper settings won't affect total roll. Springs and swaybars affect that. You can also consider going to a larger front bar, since about half (or slightly more) of the front roll resistance is dictated by the front bar. In contrast, varying the rear bar is a poor way to try and control roll there since its contribution is only about 10% to roll stiffness.

Also, you're not changing the preload of the spring at all when you adjust the height unless the damper is at full extension/droop.

[AWC-F87]

Originally Posted by FaRKle!

The KW V3 kit doesn't have particularly stiff springs. The front is 226lbs/in and rear is 685lbs/in. Those numbers are only slightly higher than the stock spring rates (by less than 10%).

You can fit stiffer springs no problem. KW uses 60mm perches, so for the front you can get an OE to 60mm ID spring adapter (like millway makes), and in the rear you can just drop in any 8" long 60mm ID standard coilover spring.

One thing you need to be careful of for the front is making sure you have enough travel before spring bind. On springs <350lbs/in you typically see the springs with the OE top mount ID and then 60mm on bottom. Above that the mfgs usually include standard coilover springs. This is because you need enough stroke/travel to avoid coil bind.

KW does make a stiffer front spring with the same format as your existing spring. It's PN 60210190 and comes from their F83 V3 kit. That spring is 265lbs/in. I'm running those springs on my Fat Cat Motorsports re-worked B14 struts on my F31. With 8" standard coilover springs I could get the spring to fully bind under some sharp and hard hits.

Playing with your damper settings won't affect total roll. Springs and swaybars affect that. You can also consider going to a larger front bar, since about half (or slightly more) of the front roll resistance is dictated by the front bar. In contrast, varying the rear bar is a poor way to try and control roll there since its contribution is only about 10% to roll stiffness.

Also, you're not changing the preload of the spring at all when you adjust the height unless the damper is at full extension/droop.

I really appreciate this information. I think I will order up a sway bar and end links, might also try to get the KW stiffer springs that you suggested.

at want point with a straight spring. not the cone OE style do I need to worry about binding. can you elaborate a little more for me about the stroke and binding. I would really appreciate this because id like to order the correct springs in one shot lol

I have ground control camber plates and would need to order a different top spring bushing if I run a straight spring. do you think the stiffer KW ones you suggested with a 30mm sway bar will be stiff enough?

looking at pictures of my car from willow springs this weekend you can see it has a lot of body roll.

[AWC-F87]

Also theoretically, if I went to a straight 60mm spring in the front would I want a slightly longer spring to maintain the usable stroke? I'm noticing in swifts charts that the longer the spring height is the more usable stroke there is. I'm guessing this will help prevent binding

[FaRKle!]

Originally Posted by AWC-F87

at want point with a straight spring. not the cone OE style do I need to worry about binding. can you elaborate a little more for me about the stroke and binding. I would really appreciate this because id like to order the correct springs in one shot lol

I have ground control camber plates and would need to order a different top spring bushing if I run a straight spring. do you think the stiffer KW ones you suggested with a 30mm sway bar will be stiff enough?

looking at pictures of my car from willow springs this weekend you can see it has a lot of body roll.

Originally Posted by AWC-F87

Also theoretically, if I went to a straight 60mm spring in the front would I want a slightly longer spring to maintain the usable stroke? I'm noticing in swifts charts that the longer the spring height is the more usable stroke there is. I'm guessing this will help prevent binding

Above 350lbs/in is pretty safe to go with a standard coilover spring (or straight as you call it). I used 60mm to 2.5"/65mm adapters so I could run 2.5" coilover springs since they have a bit more stroke before bind than 60mm ones.

I'm not sure how little body roll you're aiming for so I can't really say what will be "stiff enough" for you. You're right that you want the longest spring that you can fit (and which allows you to lower to your target height) so you have the most stroke. You can also see how much free damper travel you have before your bump stops engage since that will add extra support against coil bind.

Also, your KW coilover kit has flat ride (rear frequency higher than front, promotes chassis settling and smoother ride). Going to a front spring 250lbs/in or greater will change that to pitch unless you make your rear springs stiffer too.

If you're going to go to a stiffer sway bar anyways, why not just try that first before changing springs since it's easy to swap on these chassis?

[AWC-F87]

Originally Posted by FaRKle!

Above 350lbs/in is pretty safe to go with a standard coilover spring (or straight as you call it). I used 60mm to 2.5"/65mm adapters so I could run 2.5" coilover springs since they have a bit more stroke before bind than 60mm ones.

I'm not sure how little body roll you're aiming for so I can't really say what will be "stiff enough" for you. You're right that you want the longest spring that you can fit (and which allows you to lower to your target height) so you have the most stroke. You can also see how much free damper travel you have before your bump stops engage since that will add extra support against coil bind.

Also, your KW coilover kit has flat ride (rear frequency higher than front, promotes chassis settling and smoother ride). Going to a front spring 250lbs/in or greater will change that to pitch unless you make your rear springs stiffer too.

If you're going to go to a stiffer sway bar anyways, why not just try that first before changing springs since it's easy to swap on these chassis?

I appreciate your information as well!

I definitely agree the 30mm bar is an easy place to start.

The only reason I'm considering a slightly stiffer front spring is because under long sweeping turns if there's bumps in the track or canyon road the car will run the fender well on the outside front tire. I think the bar will help with body roll (which I'm definitely seeing in photos of the car on track) but springs may help stiffen the out side wheel a bit to prevent it from compressing so high up

[AWC-F87]

Spoke with KW USA Today. Man they are knuckleheads. If you track the car it voids the v3 warranty lol

[juicy]

Maybe try to increase the camber a little bit and check the toe.

[AWC-F87]

Originally Posted by juicy

Maybe try to increase the camber a little bit and check the toe.

I'm running over -3 front camber and proper toe. That was the first go to thing we tried

[AWC-F87]

I spoke with swift today. Leonard was extremely helpful. He also seemed very confident that the car was very under sprung for aggressive track driving.
We will be trying a linear spring and seeing if that helps.

Along with slightly increasing the ride height to gain more tire clearance in the fender Wells