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

[dukeofchen]

🤣

Kdubski, completely reasonable question but much deeper and more complicated than it seems. Too many variables involved to just rank brands.

If you want over-generalized guidelines, here's a list in no particular order:

- Bilstein
- Öhlins
- Koni
- KW
- Dinan
- Swift
- H&R
- Eibach

Not everything from those brands is good value / worth buying. But pretty much everything ELSE is either super niche (i.e., if you're asking about value, probably useless for you) or cheap to the point of being a clear downgrade from stock. There are exceptions, but that's probably a good starting point.

Also, BC Racing is not one of the exceptions. They're firmly in the downgrade category, as is everything cheaper than them.

If you want more, post a thread, tell us about your goals and preferences, and we'll help you. Sound good?

Just an idea but it would be cool to have a repository similar to the wheel setup thread for suspensions – setup, application, alignment settings, etc. Given lots of members have progressed through multiple setups I think those points of comparison in particular would be valuable.

[IamFODI]

Any opinions on JRZ relative to the other dampers discussed?

Based on my zero in-person experience...

JRZ seems to get excellent reviews for performance; not so much for quality or longevity. Seems like a good option for a low-mile weekend car or track car.

[eacmen]

Any opinions on JRZ relative to the other dampers discussed?


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[IamFODI]

bro

🤣

Kdubski, completely reasonable question but much deeper and more complicated than it seems. Too many variables involved to just rank brands.

If you want over-generalized guidelines, here's a list in no particular order:

- Bilstein
- Öhlins
- Koni
- KW
- Dinan
- Swift
- H&R
- Eibach

Not everything from those brands is good value / worth buying. But pretty much everything ELSE is either super niche (i.e., if you're asking about value, probably useless for you) or cheap to the point of being a clear downgrade from stock. There are exceptions, but that's probably a good starting point.

Also, BC Racing is not one of the exceptions. They're firmly in the downgrade category, as is everything cheaper than them.

If you want more, post a thread, tell us about your goals and preferences, and we'll help you. Sound good?

[Tbonem3]

bro

[Kdubski]

Good info in here. Is there a resource on which suspension is best for our cars? Have seen a lot of brands mentioned throughout the years and want to see how they stack up against each other. But more importantly, interested in the best value.

[eacmen]

You taken any of their other courses? Would be interesting to hear your thoughts on the suspension tuning course and any others.

So far love the content. Makes all the concepts very approachable. Would recommend.


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[wahsm]

So I am going through the HP Academy suspension tuning course. And one of the first things they want you to measure is the vertical center of gravity. Has anyone measured this for our chassis yet? I imagine it would change slightly based on ride height and any weight savings mods performed. But curious if anyone has gone through that trouble already or not?

You taken any of their other courses? Would be interesting to hear your thoughts on the suspension tuning course and any others.

[eacmen]

So I am going through the HP Academy suspension tuning course. And one of the first things they want you to measure is the vertical center of gravity. Has anyone measured this for our chassis yet? I imagine it would change slightly based on ride height and any weight savings mods performed. But curious if anyone has gone through that trouble already or not?

[cobra]

It's difficult to apply a mileage number to when you should rebuild your shocks.

-If you drive in very dirty environments it will introduce more contaminants into the oil over time and reduce the time between rebuilds.
-If you drive over very rough roads that cause a high number of movement, it will cause them to heat up more which tends to oxidize things (seals, oil) faster, as well as fatigue the valving faster.

Personally I've taken apart old, high mileage shocks that looked clean inside and still performed fine. As well as relatively new shocks that were abused and they needed everything replaced.

Our M3's are not rally cars. I imagine with a quality shock you can go many thousands of miles without needing to touch them. I would only rebuild if there was something obvious (oil leaks, shaft play, noise, loss of damping)

[0-60motorsports]

37k miles street use which seems like a conservative estimate. My buddy put 40k miles on his before selling the car. Depending on your roads, it might be possible to run them almost as long as the stock rear dampers which usually give up at 75k miles. For some owners, that would be 7+ years before needing a rebuild.

Thats great! Thanks for chiming in with your experience.

[tlow98]

I have 65k miles on my Ohlins RnT on my E90 335d which is a 3700 lb car and they still perform extremely well, but will be revalving soon as I can really feel the wear on highways and difference in wear especially. One of them is slightly bent from bumping into a curb but still works fine.

They do provide a traction boost for sure, even with almost 600 wtq the car has predictable cornering with heavy throttle at high speeds. I originally had them on my 3200 lb E92 335i which was about 500 whp and noticed a big difference in traction and control vs the previous Bilstein B4s the car had. For a street car they are really badass, comfortable dampers even with stiff sidewalled sticky tires.

Ive always been curious with the DFV. Thanks for the reference points. Also, you really did some weight reduction with that 335i! Bet that was FUN at that power:weight.

[EthanolTurbo]

Does anyone know how long before rebuild is needed for DFV?

I have 65k miles on my Ohlins RnT on my E90 335d which is a 3700 lb car and they still perform extremely well, but will be revalving soon as I can really feel the wear on highways and difference in wear especially. One of them is slightly bent from bumping into a curb but still works fine.

They do provide a traction boost for sure, even with almost 600 wtq the car has predictable cornering with heavy throttle at high speeds. I originally had them on my 3200 lb E92 335i which was about 500 whp and noticed a big difference in traction and control vs the previous Bilstein B4s the car had. For a street car they are really badass, comfortable dampers even with stiff sidewalled sticky tires.

[Obioban]

I have almost 40k miles on my R&Ts, much of which was on very bad roads, and they’re fine. Can’t say how they compare to new but I’m in no hurry to have them rebuilt or anything.

I asked Barry at 3DM how much he would charge to rebuild mine. He, who has nothing but money to gain from doing the rebuild, said there was no point in doing it till 100,000 miles.

[IamFODI]

I have almost 40k miles on my R&Ts, much of which was on very bad roads, and they’re fine. Can’t say how they compare to new but I’m in no hurry to have them rebuilt or anything.