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

[heinzboehmer]

Öhlins.

Not plug and play though. They aren't flat ride (though you can do the math and spec them with different springs through 3DM) and you need to mess with ride height adjustment a bit to get bump/droop travel into acceptable ranges.

[IamFODI]

Not plug and play though. They aren't flat ride (though you can do the math and spec them with different springs through 3DM) and you need to mess with ride height adjustment a bit to get bump/droop travel into acceptable ranges.

Fair enough.

[bigjae46]

So what would be a good option if I'm trying to keep it relatively close to stock? I'm just looking for a slightly lower ride height (less than 1") and less body roll. I only track a handful of times a year so I'm not ready to commit to a 5k MCS/JRZ setup, and it is a daily and canyon car as well. TCK S/A or koni yellows paired with dinan springs (I think this is ez flat ride?) are what currently what I've narrowed it down to from my research, but open to suggestions.

I have the TCK x2s with their 450lb springs in the front. My front ride height peaks at 13.75" from fender to the center of the wheel with -4.0 camber. I know if you run less camber then your ride height will change, forget which way. The adjusters are near the top, I can maybe squeeze another 1/4"? Not sure how close to stock that would be. I have a finger width gap between the tire and fender.

The rear is easy, I could probably be a half inch higher than stock.

[bavarian3]

Has anyone done this with JRZ's? I bought a set of RS Two's and am looking for some springs to complete the kit. Perhaps overthinking it but I'm wondering if there could be issues up front with such a soft spring if the damper is valved for a higher rate.

[Cronenberged]

Has anyone done this with JRZ's? I bought a set of RS Two's and am looking for some springs to complete the kit. Perhaps overthinking it but I'm wondering if there could be issues up front with such a soft spring if the damper is valved for a higher rate.

I mean Cobra built his off of Fox's with piggy backs, so yes. You just have to get them tuned for your application. I grasp it enough to understand the spring rates, but tuning a shock to your needs that's a whole different science and I paid FCM for this.

[cobra]

Has anyone done this with JRZ's? I bought a set of RS Two's and am looking for some springs to complete the kit. Perhaps overthinking it but I'm wondering if there could be issues up front with such a soft spring if the damper is valved for a higher rate.

I mean Cobra built his off of Fox's with piggy backs, so yes. You just have to get them tuned for your application. I grasp it enough to understand the spring rates, but tuning a shock to your needs that's a whole different science and I paid FCM for this.

You would probably need to revalve if you change the spring rate too much. There is some wiggle room with the adjuster but once you get out of that range you will not be properly matched anymore. In my experience with basic valving, a standard architecture, and single bi-directional shaft adjuster, you can go about +/- 10% in spring rate before it gets noticeably compromised.
That is, of course, assuming it was tuned properly in the first place.

[OldRanger]

Obioban I’m going to compare the Ohlins 628# rear to the TCK 700# rear paired with the Ohlins 400 fronts for on track duty with Intermediate drivers.

This Ohlins 628# stack (as set by RRT) measures to 6.5” inches and results in a 13” ride height. The TCK 700 stack is different. When the perch is fully lowered on the threads of the TCK ride height adjuster, this spring g has a 6.5” stack at the highest point of the coil, note that coil is not wound as flat at the top as the Ohlins.

I’m going to try these rear springs now.

I have a new GC front sway that I’m going to keep soft or medium soft. I have a square wheel setup with 265s and a -2.5 camber front -2.2 rear. On Tuesday I have an alignment and corner balance and asking for a bit more negative camber front.

Note: TCK springs do not pair well with the Ohlins plastic

[cobra]

Obioban I’m going to compare the Ohlins 628# rear to the TCK 700# rear paired with the Ohlins 400 fronts for on track duty with Intermediate drivers.

This Ohlins 628# stack (as set by RRT) measures to 6.5” inches and results in a 13” ride height. The TCK 700 stack is different. When the perch is fully lowered on the threads of the TCK ride height adjuster, this spring g has a 6.5” stack at the highest point of the coil, note that coil is not wound as flat at the top as the Ohlins.

I’m going to try these rear springs now.

I have a new GC front sway that I’m going to keep soft or medium soft. I have a square wheel setup with 265s and a -2.5 camber front -2.2 rear. On Tuesday I have an alignment and corner balance and asking for a bit more negative camber front.

Note: TCK springs do not pair well with the Ohlins plastic

How long are each of those springs out of curiosity?

[OldRanger]

How long are each of those springs out of curiosity?

Do you want me to measure the length of the material?

if just simply the vertical dimension:
- Ohlins are both 5 1/8”
- TCK one is 6”, one is 6 1/8”