Suspension dilemma: KW or JRZ?

[kaiv]

A little background:

I've had an E36 on Bilstein PSS, E46 on KW V2, E90 on KW V3s.

The monotube Bilsteins were valved too stiff IMHO.

The KWs, I loved. They were smooth yet handled track work like a champ. I tracked my E46 for 3 years. Plus the V2s are 1 way so easy to adjust.

Then I moved on to an E90. I was so satisfied with KW that I got that again. V3s this time.

They were perfect on the E90. Super smooth ride and great on the track. Keep in mind the car doubles as my daily driver.

If anything I felt they were a little slow in quick transitions on a big car like that but I'm thinking I that could've probably been adjusted.

The other thing is adjusting this stuff is not exactly my forte. If you ask me on a 2 way setup there's one too many knob I like the simplicity of a 1 way setup. I like to drive rather than messing around and trying different settings that are independently adjustable yet affect each other o_O

Now I have an E92 and I'm looking for suspension.
I've narrowed it down to 3 choices:

A) KW Clubsport (the 2-way version).
A step up in track performance from the V3s I'm used to. I wonder how they ride though. I do care about my street comfort.

B) KW V3 with GC street plates. What I had in the E90. Loved it but again I wouldn't mind trying something new, something that's faster around a track!

C) The newer JRZ RS1. Not many reviews out there but they seem like great dampers. People kinda make it seem as if they are comfy as V3s yet as fast as Clubsports. Could that be true? I do like that they are 1 way adjustable for simplicity's sake. They are not cheap though compared to the KWs. I'm also concerned they might be stiff due to being monotube.

So there you have it. I would love to hear you guys' opinions, especially those who both track and daily their M3.

[STALKER]

Having used KW CS, Moton SS, Dinan Stage 1 with camber plates and now JRZ RS1.

The RS1s are superior to all of them as a dual purpose set up. You can search for my threads and read my reviews.

[zsapphire7]

Originally Posted by kaiv

A little background:

I've had an E36 on Bilstein PSS, E46 on KW V2, E90 on KW V3s.

The monotube Bilsteins were valved too stiff IMHO.

The KWs, I loved. They were smooth yet handled track work like a champ. I tracked my E46 for 3 years. Plus the V2s are 1 way so easy to adjust.

Then I moved on to an E90. I was so satisfied with KW that I got that again. V3s this time.

They were perfect on the E90. Super smooth ride and great on the track. Keep in mind the car doubles as my daily driver.

If anything I felt they were a little slow in quick transitions on a big car like that but I'm thinking I that could've probably been adjusted.

The other thing is adjusting this stuff is not exactly my forte. If you ask me on a 2 way setup there's one too many knob I like the simplicity of a 1 way setup. I like to drive rather than messing around and trying different settings that are independently adjustable yet affect each other o_O

Now I have an E92 and I'm looking for suspension.
I've narrowed it down to 3 choices:

A) KW Clubsport (the 2-way version).
A step up in track performance from the V3s I'm used to. I wonder how they ride though. I do care about my street comfort.

B) KW V3 with GC street plates. What I had in the E90. Loved it but again I wouldn't mind trying something new, something that's faster around a track!

C) The newer JRZ RS1. Not many reviews out there but they seem like great dampers. People kinda make it seem as if they are comfy as V3s yet as fast as Clubsports. Could that be true? I do like that they are 1 way adjustable for simplicity's sake. They are not cheap though compared to the KWs. I'm also concerned they might be stiff due to being monotube.

So there you have it. I would love to hear you guys' opinions, especially those who both track and daily their M3.

The stiffness is not determined by monotube vs twin tube but by the spring rates. You can always specify softer rates or comparable rates to that of the KWs and have JRZ valve the shocks specific for your springs rates! KW you get what they offer in terms of of the shelf rates.

[grussell]

Originally Posted by STALKER

Having used KW CS, Moton SS, Dinan Stage 1 with camber plates and now JRZ RS1.

The RS1s are superior to all of them as a dual purpose set up. You can search for my threads and read my reviews.

I currently have Dinan stage 1 with camber plates on a ZCP E92. Can you describe the pros and cons moving from this setup to the RS1's?

[ikarishinjikun]

I would first like to say I was in your same exact situation. I have an E90 and found it hard to decide what suspension to upgrade to. I previously had the Dinan Stage 3 kit matching the competition pack on my 2011 and found that to be sufficient for day-to-day commuting and the occasional track day. But once I began going to the track more often I realized a need to change the suspension.

Debating between the KW CS and JRZ, I chose JRZ and I can say the ride of the car has changed dramatically compared to what I had before, in a good way. Unfortunately, I can not comment on the RS1 as I have the RS-Pro, I hope my opinion and review below helps you.

Daily Driving: The car behaves pretty much like the stock suspension. I soaks up bumps pretty well in the city (San Francisco) are is not horribly bouncy. My settings for the street are 7 click on the bump and 4 on the rebound on every corner. Freeway driving is smooth but there will be some increase in the noise due to the Vorshlag camber plates.

Track Driving: I was able to test the car out a couple weekends ago at Sears Point for the first time. On the track is where this suspension shines the most. With my settings for street driving the vehicle handled pretty well and when loading in the corners (3 and 3a comes to mind) but some increases in the bump could be done to improve handling. The rebound setting was good at 4 but minor tweaks could be made.

Overall Opinion: JRZ makes an excellent damper for both street and track driving, but tuning is crucial. JRZ also provides excellent support since there was a snag during the installation process they were prompt with their replies and willing to assist in any way possible.

Pros: Excellent damper for both street and track, Easy to adjust (because of the external reservoir), Excellent customer support

Cons: Race damper (i.e. troubleshooting is necessary, this is a race part), quick disconnects need to be ordered on both front and rear for ease of installation, slight increase in noise from the camber plates, extension for rear bump adjustment should be pre-ordered

I hope my opinion on the JRZ assists you in some way.

Thanks.

[kaiv]

Originally Posted by STALKER

Having used KW CS, Moton SS, Dinan Stage 1 with camber plates and now JRZ RS1.

The RS1s are superior to all of them as a dual purpose set up. You can search for my threads and read my reviews.

I actually read your thread with great interest! Thank you!

It looks like we use our cars the same way (dd+ track) + you have experience with the KWs too so I definitely took your observations into account.

A friend of mine who has lots of track experience on different setups told me that the RS1 is the superior setup (technology) but that the good old 2way clubsport is the better/faster setup once everything is dialed in. I suppose it's easy to mess up the setup and have a not so stellar experience with the Clubsports.

Either way I haven't made my mind but I'm just not sure if I want to shell out all the extra cash for the RS1. Clubsports can be found for 2800ish new.

Decisions decisions!

Originally Posted by zsapphire7

The stiffness is not determined by monotube vs twin tube but by the spring rates. You can always specify softer rates or comparable rates to that of the KWs and have JRZ valve the shocks specific for your springs rates! KW you get what they offer in terms of of the shelf rates.

I was under the impression that -all other things equal- the monotube setup would be stiffer than its twin tube counter part. (Perhaps a useless statement though since spring rates would vary from a setup to another!)

[Martin_D]

JRZ without a question. Owned both, on numerous cars.

[PINHEAD]

skip the RS1 and just get the RS/RS Pro.
Ive had KW CS before and JRZ RS damper is just in another league.

[kaiv]

RS and RS pro are just way above my price range. I need to have $ leftover to buy tires and pads too!

So if I go with JRZ's offering it's RS1 or nothing.

Also can you guys expand a bit on your experience? It's a lot of coin to drop just based on someone saying " I had both and JRZ is much better"

[EDDYFIG]

I love my KW's V3

[xchosun1x]

hey kev...maybe a custom app kwv3 is a option that is both economical with performance

perhaps a stiffer spring ie hypercoil or swift, w kw v3 shocks, w camber plates?

hope that helps w anything

[klammer]

I am in an almost identical situation. Have been rocking the D Stg 3 for almost 2 years and IMHO it's the prefect compromise setup for price and performance. That being said... After falling in pretty deep tracking the car, feel the need for a change and have always felt handling is the way to go. With people spending 10-15 large on blowers, thinking the JRZ aren't that bad if that's the route you prefer, I do... To further the discussion what are the benefits of the certain JRZ lines...why would one pick one over the other?

[dawgdog]

I have AST suspension, first 5220 and now 4200. I have nothing but good things to say about the 4200 series. Comfortable on the street and dialed in on the track. I had some issues with the 5200 series and prefer the simplicity of two way without remote reservoirs. Whatever you get make sure the vendor has done the setup successfully and that you are not the beta tester! Harold at HP Autowerks put my 4200 kit together and no issues. My installer has put a lot of suspensions in e9xM3s and prefers the 4200 to others he has installed.

[EAS]

Originally Posted by Martin_D

JRZ without a question. Owned both, on numerous cars.

+1.

Kaiv: Gabe just had a set of RS1's installed on his VF620 M3, we'll see if we can arrange a ride on the next track session.

[bigjae1976]

I think the main advantage of the JRZs is that you can customize the dampers and spring rates. If you don't want to F' with your car and change springs and settings...then the KWs might be the way to go. But KW is the only coilover setup in this price range that doesn't readily offer different spring rates. Or I am just not aware of it.

[lutfy]

Originally Posted by bigjae1976

I think the main advantage of the JRZs is that you can customize the dampers and spring rates. If you don't want to F' with your car and change springs and settings...then the KWs might be the way to go. But KW is the only coilover setup in this price range that doesn't readily offer different spring rates. Or I am just not aware of it.

You can change the spring rates on the KWV3s as well. I had my kit tweaked by RobiSpec (Robert Fuller, he is well known in the Evo/Sti community) on my Sti. I did like my shocks/setup for DD no complains.

If you are going custom, JRZ is a great product (have used that on my Euro E36 M3 track car). I got this because of service (plug and play, support) from James Clay and his team. You CANT go wrong, do it!

People in America only know KW with CS and V3s. However, KW also makes custom coilovers. We had one made, you get a spec sheet writing down everything from weight to tires you'll use and setup and send it to KW Europe and they custom make the kit using spec spring rates (per your input) and comes with camber plates. GREAT product, many 24 Hour Enduro cars (non factory race cars) run KW Competitions (double adjustable) including many BMWs. So dont underestimate that.

If in the US, I would get the JRZ because you will find more folks running a comp setup on the track and Bimmerworld is always out there somewhere to assist you (buy James some spicy food and he will take your car out and assist

Hope this helps.

Lutfy

[GTM_Challenge]

Originally Posted by klammer

I am in an almost identical situation. Have been rocking the D Stg 3 for almost 2 years and IMHO it's the prefect compromise setup for price and performance. That being said... After falling in pretty deep tracking the car, feel the need for a change and have always felt handling is the way to go. With people spending 10-15 large on blowers, thinking the JRZ aren't that bad if that's the route you prefer, I do... To further the discussion what are the benefits of the certain JRZ lines...why would one pick one over the other?

JRZ offers from 1 way up to 4 way race dampers. So depending on your needs, budget, and also you understanding of suspension tuning there is basically a solution out there for you. The 3 and 4 ways allow high or low speed rebound/bump adjustment

[TC Kline Racing]

Originally Posted by kaiv

A little background:

I've had an E36 on Bilstein PSS, E46 on KW V2, E90 on KW V3s.

The monotube Bilsteins were valved too stiff IMHO.

The KWs, I loved. They were smooth yet handled track work like a champ. I tracked my E46 for 3 years. Plus the V2s are 1 way so easy to adjust.

Then I moved on to an E90. I was so satisfied with KW that I got that again. V3s this time.

They were perfect on the E90. Super smooth ride and great on the track. Keep in mind the car doubles as my daily driver.

If anything I felt they were a little slow in quick transitions on a big car like that but I'm thinking I that could've probably been adjusted.

The other thing is adjusting this stuff is not exactly my forte. If you ask me on a 2 way setup there's one too many knob I like the simplicity of a 1 way setup. I like to drive rather than messing around and trying different settings that are independently adjustable yet affect each other o_O

Now I have an E92 and I'm looking for suspension.
I've narrowed it down to 3 choices:

A) KW Clubsport (the 2-way version).
A step up in track performance from the V3s I'm used to. I wonder how they ride though. I do care about my street comfort.

B) KW V3 with GC street plates. What I had in the E90. Loved it but again I wouldn't mind trying something new, something that's faster around a track!

C) The newer JRZ RS1. Not many reviews out there but they seem like great dampers. People kinda make it seem as if they are comfy as V3s yet as fast as Clubsports. Could that be true? I do like that they are 1 way adjustable for simplicity's sake. They are not cheap though compared to the KWs. I'm also concerned they might be stiff due to being monotube.

So there you have it. I would love to hear you guys' opinions, especially those who both track and daily their M3.

Have you considered the TC Kline Racing suspension options? We do offer all of our suspensions with customized spring rates, lifetime warranty, and pride ourselves on a suspension that improves street comfort and track performance. Also we provide you with the shock and alignment settings for street and track

Just a thought If you would like to know more please let us know!

[JamesClay]

It isn't all about spring stiffness - the damper valving is a big component of comfort and handling. That gets talked about in the forums a lot to varying degrees of correctness. Number of adjustments is somewhat relevant among dampers in one product line, but just another item on the comparison list and by far not more important than the true capability of those adjustments.

Black on black, 2-door, V8 engine, 6-speed transmission, 18" wheels - I just described our E92 M3 magazine car...and a Toyota Tundra pickup truck in our parking lot. Its not about a spec sheet, its about what those specs really mean. Damper internals and design is one of the things I never really hear much about on the forums, past the tribes that are told to push monotube, which is really just a design philosophy and again, not superior to another depending on the execution. I think this aspect is a little harder for the average expert to post on because it take someone who has been inside multiple types of dampers, played with them to create different characteristics, and understands how that plays out in real life on the street or the racetrack.

The fact is that a JRZ or a lot of the premium high-end stuff is really pretty impressive inside - well, and outside. They are very rugged, precision machined parts (many of which are very complicated), and with high tolerances and very precisely assembled. This stuff really is a work of art that someone that enjoys mechanical design and precision would really appreciate - I know that as a guy with an engineering background, I admire what they are able to accomplish.

More production-line type dampers like a KW, Bilstein, etc just don't have the same approach. We have had dampers of this level apart as well and worked to make them perform as well as a premium race damper and they just don't. Precision aside, design is critical and goes way deeper than changing "monotube" or "twin-tube" - either of those works, but certainly there is elegance and simplicity in some designs versus others.

This is not a slight to the lower-cost, higher-production dampers that are not small-batch and hand-assembled - these cheaper dampers many times do a great job, fill a need in the market, and can be quite good parts. But no one that has been inside one of these, or riden in a car with them and experienced the range and ability of control, should be scratching their head about why a more expensive damper is better than the cheaper stuff.

And while you can hot-rod and revalve dampers, you just can't change the internal design. You can cover different spring rates with a cheaper damper by changing shim stacks or pistons, just like I could go outside and put Hoosiers on that Tundra pickup, but they aren't going to perform like their counterparts that were built from the ground up with a different goal and philosophy.

Feel free to contact me directly via phone or email to discuss further. For now, I'm off the forum and back to the projects we have going on here.

[rzm3]

Kevin, how often do you track and which run group are you in? This is very important to choosing the right suspension.

In the mean time, some food for thought...

1) As many have mentioned, ride quality is a function of spring rates and damping among other things. For spring rates one would consider on a dual purpose M3, I would say that damping will have a far greater impact than spring rates. (I've driven my car without rear dampers)

2) Don't read too much into the whole premium or non-premium marketing tag lines. Premium is a very vague/ambiguous term (and that's why it's used). Look into the specs and real results.

3) Compression and rebound do control some distinct characteristics of a suspension, and that's the value of 2-way all the way to 5-way dampers. I do agree that even 2-way may be too much at times, but my approach is always to have a pro driver drive your car to tune it in based on your set up, and then just leave it alone until you make a major change to the car.

4) KW Clubsport 2-way rides similar to ZCP 'Sport' mode, if not slightly stiffer. 2-way's compression knob adjusts low-speed compression only, so depending on where you live and track, the high-speed circuit, which is non-adjustable, could be too stiff. This is where the 3-way comes into play where you can independently adjust low- and high-speed compression for optimal ride quality. (But just as a reference, I've installed many and driven even more KW Clubsport 2-way equip'd M3s and don't remember meeting any owners who thought they were too stiff)

[STALKER]

Can find some reviews on the RS1 by our 1M friends here.
http://www.1addicts.com/forums/showthread.php?t=614496

[Porschefile]

I have KW CS and like them a lot, but I've always wondered what makes the JRZ better. I understand it is better built, but does that translate into an actual lap time improvement or is it just like "my rolex is better built than your watch" but it does the same thing.

Are JRZ/Moton/whatever actually faster than the track oriented KW's, and if so, is it a difference that a normal track driver can appreciate, as opposed to a .2 second benefit that only a handful of even experienced drivers can appreciate?