e46 M3 suspension setup, or how to not downgrade your car with suspension mods

[Thoglan]

Hmm, seems like you’re right.

well, something is different and I forget what, it seems. Whatever it is, the result is that the US cars need the strut spacer and the euro cars don’t.

Yeah weird, Euro car here and with ohlins and GC street camber plates I sit at about 13.25" hub to fender with the right bump/droop without the use of the spacer. When using the spacer it put me further outside of the range. Not sure what else would be different in the geometry though.

[Obioban]

Euro and US m3s use the same kingpins.

Hmm, seems like you’re right.

well, something is different and I forget what, it seems. Whatever it is, the result is that the US cars need the strut spacer and the euro cars don’t.

[jet_dogg]

The strut spacer is the result of the setup being developed with european kingpins and US kingpins being different.

Euro and US m3s use the same kingpins.

[Tbonem3]

Ok so then it does seem that they engineered them for the taller/thicker stock mounts :/

Too bad stock mounts are as expensive as camber plates these days!

[Obioban]

Ah ok. I'm not up to speed on the ohlins and that spacer issue. I want as much travel as possible at a pretty low height of like 13.25" so maybe someone like me wouldn't even bother with the spacer.

Is the concern, without a spacer, that the car would sit too low with aftermarket plates?

Couldn't you just move the bottom perch upwards to compensate? Droop will be very short, I imagine.

The problem is that the Ohlins have very little total travel-- so to have them function properly, you pretty much MUST optimize ride height for bump/droop travel.

Without the strut spacers on a US spec car, you have to be lower than the suspension geometry is good for. Similarly any camber plate that increases bump travel too much does the same.

[Obioban]

There's a caveat on this with the Ohlins, isn't there? Hence the need for those 3DM spacers when you shorten the stack height with aftermarket camber plates. I was always under the impression that the R&T struts were designed specifically for stock top mounts, leading to the ride height issues without the strut spacers.

The strut spacer is the result of the setup being developed with european kingpins and US kingpins being different.

[Tbonem3]

Ah ok. I'm not up to speed on the ohlins and that spacer issue. I want as much travel as possible at a pretty low height of like 13.25" so maybe someone like me wouldn't even bother with the spacer.

Is the concern, without a spacer, that the car would sit too low with aftermarket plates?

Couldn't you just move the bottom perch upwards to compensate? Droop will be very short, I imagine.

[r4dr]

IMO, using stock mounts defeats a very useful feature of aftermarket coilovers/plates for us - reducing ride height for free through reduction of stack height in camber plates from GC, Vorshlag, TMS and probably others.

If you just want stock like height (14"+) then you'll have plenty of travel I suppose.

There's a caveat on this with the Ohlins, isn't there? Hence the need for those 3DM spacers when you shorten the stack height with aftermarket camber plates. I was always under the impression that the R&T struts were designed specifically for stock top mounts, leading to the ride height issues without the strut spacers.

[Tbonem3]

I should have said that it'll depend on strut. I have MCS and can run anything I want, bottom perch height-wise - plenty of adjustment. On my Bilstein b6 with GC conversion, 7" was 325lb so at 400lb, I would look for 6.25" like tck vvs or a 6" with extended travel like eibach's xt.

I run tck 400lb which is only in 60mm & it says 6.5" but really is 6.25" tall.

[mrgizmo04]

Do you know the rear spring rate for the Ohlins? I’m assuming the 400# F are for the R&Ts?

The last sentence of my post lists them at 628

Sent from my SM-G950U using Tapatalk

[lvm3sm46]

Rear is 630 for the R&T

[duracellttu]

FWIW, Ohlins comes with a 8" 400 front spring and that provides almost an inch drop with stock front mounts.

If you try running a 350 7" spring at 13.5 ride height, you will be almost at the very top of adjustment threads on the collar after preloading the spring appropriately (ride height and spring preload same adjuster).

I tried a 336 7" spring and could not get it to more than barely above 13.25 after maxing out the adjustment collar/preload. The tire rubbed.

Rears at 628 I believe are 6" long (they might be 5", ill need to check).

Sent from my SM-G950U using Tapatalk

Do you know the rear spring rate for the Ohlins? I’m assuming the 400# F are for the R&Ts?

[lvm3sm46]

Ive seen the Turner ones recommended here, https://www.turnermotorsport.com/p-3...s-pair/?pdk=Bw

[DropTopKingM3]

I’m about to have ohlins road and track installed on my car. I’m not sure if they came with front and rear endlinks. Would the Moog K6662 work with these ?
If not which ones are recommended?

[mrgizmo04]

FWIW, Ohlins comes with a 8" 400 front spring and that provides almost an inch drop with stock front mounts.

If you try running a 350 7" spring at 13.5 ride height, you will be almost at the very top of adjustment threads on the collar after preloading the spring appropriately (ride height and spring preload same adjuster).

I tried a 336 7" spring and could not get it to more than barely above 13.25 after maxing out the adjustment collar/preload. The tire rubbed.

Rears at 628 I believe are 6" long (they might be 5", ill need to check).

Sent from my SM-G950U using Tapatalk