Coil Over Kit - Need Input

[JFWM3]

Guys,

I need some input. My car is summer driven on some pretty bad winter damaged roads, and I do some light tracking. The car is a 6MT FI E92 with some other mods and currently has a Ground Control EDC kit on it. I am looking to upgrade, and I am considering:
A. TCK
B. JRZ
C. Ohlins

I have a couple of considerations. I want to be able to drive my car and not lose the fillings in my teeth (I will go with lighter spring rates). I really don't want to routinely rebuild whatever kit I install. I want the tuning complexity to be realistic to my street/light tracking driving environment. I have intermediate training in open wheeled formula Van Dieman's, and recognize that despite the fact that we all believe we are "driving gods", my opinion is most people don't have the skill level to tune/track to the level of a DA kit


Couple questions.
1. Which kits require some form of rebuild at a prescribed frequency (ie. I think Ohlins has to be rebuilt every 20,000 miles)?

2. Which is more suitable street/light tracking - DA or SA?


I appreciate the input!

[jacobe92]

I'm currently running JRZ RS dampers w/ Ground Control components plus Swift Springs 450/700 spring rates. I think it's perfect for my application. A daily driver plus one weekend a mos of track. Recommend rebuild of dampers every 30,000 miles. My set up before this was a KW Clubsports which was very quiet like oem. Ground Controls are noisy "down side."

[tom @ eas]

Originally Posted by jacobe92

I'm currently running JRZ RS dampers w/ Ground Control components plus Swift Springs 450/700 spring rates. I think it's perfect for my application. A daily driver plus one weekend a mos of track. Recommend rebuild of dampers every 30,000 miles. My set up before this was a KW Clubsports which was very quiet like oem. Ground Controls are noisy "down side."

Completely agree. Hands down, you will not be disappointed with the JRZ RS-Pros.

Here's a recent install on a Frozen Red M3:







We are an authorized JRZ retailer, let me know if you have any questions on the systems and I will be glad to assist.

[aus]

Those are all awesome coils, but for what you do, just get some KW's with the lifetime warranty and be done with it. I've read some issue or another with most of the high end coils mentioned- never in a thread praising how awesome they are- maybe they've fixed all the issues by now, but KW's are proven and many kits have been sold, so issues should be fixed by now.

.

[PrimeBMW]

I would also recommend you consider MCS single adjustable. High quality damper that is not too complex to tune. They also have outstanding support. You just don't hear about them much because there are not many authorized dealers. I can provide one if you like.

[kchu221]

Originally Posted by jacobe92

I'm currently running JRZ RS dampers w/ Ground Control components plus Swift Springs 450/700 spring rates. I think it's perfect for my application. A daily driver plus one weekend a mos of track. Recommend rebuild of dampers every 30,000 miles. My set up before this was a KW Clubsports which was very quiet like oem. Ground Controls are noisy "down side."

im glad youre liking the JRZ brotha!! the OP missed out on a good sale...

[dogbone]

I'll chime in for JRZ too. I have RS Pro. You could do well with the single-adjustable RS1 and keep the price in a generally reasonable range. Remember, single adjustable doesn't mean you're only controlling one parameter. Single adjustable means you turn one knob, and JRZ has predetermined how both rebound and compression change, so the complexities of tuning are drastically reduced.

And JRZ is ABSOLUTELY OPPOSITE a stiff, bone jarring suspension when paired with proper springs. It's actually plush. I know that may sound silly, but it's true. Paired with appropriate springs (450-550 front, 650-750 rear), the car will be more comfortable than stock on the street, and then when you dial up the settings for track, it will be very capable.

[Exclusivs]

Great thread OP. In a similar situation myself. Running KWV3 on my car now. More then capable setup for the street and occasional track duty. Comfort is there, not one day have I missed EDC. Are KW Clubsport not on your list?

Originally Posted by jacobe92

I'm currently running JRZ RS dampers w/ Ground Control components plus Swift Springs 450/700 spring rates. I think it's perfect for my application. A daily driver plus one weekend a mos of track. Recommend rebuild of dampers every 30,000 miles. My set up before this was a KW Clubsports which was very quiet like oem. Ground Controls are noisy "down side."

No thread jack - Can you chime in on KW Clubsport vs your JRZ setup

[JFWM3]

Originally Posted by kchu221

im glad youre liking the JRZ brotha!! the OP missed out on a good sale...

I don't know, you were just so hard to deal with, that I walked away!

Kidding, and yeah I will admit, maybe I missed out on one!

[JFWM3]

Originally Posted by dogbone

I'll chime in for JRZ too. I have RS Pro. You could do well with the single-adjustable RS1 and keep the price in a generally reasonable range. Remember, single adjustable doesn't mean you're only controlling one parameter. Single adjustable means you turn one knob, and JRZ has predetermined how both rebound and compression change, so the complexities of tuning are drastically reduced.

And JRZ is ABSOLUTELY OPPOSITE a stiff, bone jarring suspension when paired with proper springs. It's actually plush. I know that may sound silly, but it's true. Paired with appropriate springs (450-550 front, 650-750 rear), the car will be more comfortable than stock on the street, and then when you dial up the settings for track, it will be very capable.

I am starting to like the idea of a SA kit more and more.

[bigjae1976]

First, the adjustment knobs have very little to do with actual comfort and should be used for that purpose. The quality of the damper and using properly matched springs are the key to a comfortable but high performing coil over.

With that said, I have the TCK d/a on my E46 and I have touched the adjustments twice. I do drive it on the street occasionally and it is surprisingly comfortable and quite capable on the track.

Not saying that the TCKs are better than the JRZ or Ohlins but as far as lap times go...I'll put my TCKs against them any day of the week. The one thing I like is TC Kline does the R&D and setup on the actual car it is going on, you know its good right out of the box.

If you want comfort...I've never ridden in a KW equipped car that I thought was comfortable. They all have been hard and/or bouncy. Their competition coilover on the E46 M3 gave me back pain. I'm not a fan.

I think MCS would be another one to look at that seems to be gaining popularity.

[kchu221]

Originally Posted by JFWM3

I don't know, you were just so hard to deal with, that I walked away!

Kidding, and yeah I will admit, maybe I missed out on one!

hahah bro i was willing to work with you till the end and gave you a bombass deal....

[dogbone]

Originally Posted by bigjae1976

First, the adjustment knobs have very little to do with actual comfort and should be used for that purpose. The quality of the damper and using properly matched springs are the key to a comfortable but high performing coil over.

With that said, I have the TCK d/a on my E46 and I have touched the adjustments twice. I do drive it on the street occasionally and it is surprisingly comfortable and quite capable on the track.

Not saying that the TCKs are better than the JRZ or Ohlins but as far as lap times go...I'll put my TCKs against them any day of the week. The one thing I like is TC Kline does the R&D and setup on the actual car it is going on, you know its good right out of the box.

If you want comfort...I've never ridden in a KW equipped car that I thought was comfortable. They all have been hard and/or bouncy. Their competition coilover on the E46 M3 gave me back pain. I'm not a fan.

I think MCS would be another one to look at that seems to be gaining popularity.

hmmmm......respectfully, I have to disagree with the statement that the adjustment knobs have "very little to do with actual comfort".....at least in JRZ's case. In JRZ-land, the adjustment knobs affect the attitude of the car quite a bit-----especially the rebound setting. When you chill out the rebound setting on JRZ, the whole car mellows out, meaning that it goes with the flow of the street and isn't jittery at all. As I mentioned before, the car can be mellower and more plush than with the stock suspension-----something that you would not necessarily expect from a track-capable suspension. However, when you start dialing the rebound up----and there are 22 clicks of rebound adjustment on RS Pro----the car starts to react to every little nuance in the road surface, and on the street, where the surface sucks in LA, the car gets quite jittery. It's not pleasant to drive the car on the street with the rebound setting in "attack" mode. And I'd even argue that there are very few tracks that are smooth enough where you can drive the car properly with rebound turned most of the way up.

I've tracked my fair share at this point (≈60 days). I have a document on my phone dedicated to suspension settings for each track that I go to. Each track has different settings. For instance, Buttonwillow is a humpy bumpy berm hopping nightmare for the suspension, but Laguna Seca is the smoothest thing your car will see as far as tracks go in CA, and they put those nasty huge, car-ruining bumps at the apexes of the corners at Laguna to keep you from cutting corners. If you have an adjustable suspension, running the same suspension settings at these two tracks would be the incorrect way to go. When you're on a rough track attacking berms, you need to dial the rebound back---slow it down, otherwise you bounce off of those features, and that's not going to do you any favors. But at Laguna Seca, where it's super smooth, you want that car to be nice and tight and reactive to every little thing because nothing big comes up there that will make the car hop. Remember, the suspension's job is to keep your tire in contact with the road surface. The more your tire is bouncing off of things, the less control you will have and the less fast you will go. So, you have to take into consideration what kind of road surface you're driving on, and then adjust from there.

At the end of the day, there are plenty of good suspensions out there for the E9x M3. Ultimately, driver ability is what determines lap times. Saying that "my suspension produces good lap times" is fine and true to a point, but there are so many other factors involved. Honestly, if someone just wants fast lap times, just stick Hankook TD and a big wing on any M3, and it will FLY with those two additions. Suspension would help in that case too.

[bigjae1976]

Originally Posted by dogbone

hmmmm......respectfully, I have to disagree with the statement that the adjustment knobs have "very little to do with actual comfort".....at least in JRZ's case. In JRZ-land, the adjustment knobs affect the attitude of the car quite a bit-----especially the rebound setting. When you chill out the rebound setting on JRZ, the whole car mellows out, meaning that it goes with the flow of the street and isn't jittery at all. As I mentioned before, the car can be mellower and more plush than with the stock suspension-----something that you would not necessarily expect from a track-capable suspension. However, when you start dialing the rebound up----and there are 22 clicks of rebound adjustment on RS Pro----the car starts to react to every little nuance in the road surface, and on the street, where the surface sucks in LA, the car gets quite jittery. It's not pleasant to drive the car on the street with the rebound setting in "attack" mode. And I'd even argue that there are very few tracks that are smooth enough where you can drive the car properly with rebound turned most of the way up.

I've tracked my fair share at this point (≈60 days). I have a document on my phone dedicated to suspension settings for each track that I go to. Each track has different settings. For instance, Buttonwillow is a humpy bumpy berm hopping nightmare for the suspension, but Laguna Seca is the smoothest thing your car will see as far as tracks go in CA, and they put those nasty huge, car-ruining bumps at the apexes of the corners at Laguna to keep you from cutting corners. If you have an adjustable suspension, running the same suspension settings at these two tracks would be the incorrect way to go. When you're on a rough track attacking berms, you need to dial the rebound back---slow it down, otherwise you bounce off of those features, and that's not going to do you any favors. But at Laguna Seca, where it's super smooth, you want that car to be nice and tight and reactive to every little thing because nothing big comes up there that will make the car hop. Remember, the suspension's job is to keep your tire in contact with the road surface. The more your tire is bouncing off of things, the less control you will have and the less fast you will go. So, you have to take into consideration what kind of road surface you're driving on, and then adjust from there.

At the end of the day, there are plenty of good suspensions out there for the E9x M3. Ultimately, driver ability is what determines lap times. Saying that "my suspension produces good lap times" is fine and true to a point, but there are so many other factors involved. Honestly, if someone just wants fast lap times, just stick Hankook TD and a big wing on any M3, and it will FLY with those two additions. Suspension would help in that case too.

There is a range of adjustability that helps to fine tune. But the reason why you have had such good results is that you have springs that are properly matched to your damper. What a coilover like a JRZ does is allow higher spring rates than the TCK setup with pretty good koni struts. If you ran much stiffer springs and ran the adjustment down to the min or slowest adjustment the car would bounce your head off the roof.

The adjustments on the damper are NOT for comfort. Adjustments are for adjusting the speed of the shock. Turning it "down" is slowing the reaction of the shock which follows your observation of not following every bump and mouse turd in the road. The result might be more comfort but you're not going to run 1000lb springs on the front and expect it to ever be comfortable. Turn it "up" speeds up the reaction to put more weight on the tire and also reduce body roll (less weight transfer) resulting in more grip (probably not the best explanation).

I'm running the highest spring rate that my TCKs are designed to handle and the car gets bouncy at the lower end of my adjustment range. But I don't see too many people running higher spring rates that still have street legal cars.

[jacobe92]

Originally Posted by Exclusivs

Great thread OP. In a similar situation myself. Running KWV3 on my car now. More then capable setup for the street and occasional track duty. Comfort is there, not one day have I missed EDC. Are KW Clubsport not on your list?

No thread jack - Can you chime in on KW Clubsport vs your JRZ setup

I've only had my JRZ RS 450/700 at the track twice and one thing I've noticed that it's more sensitive compared to my previous KW CS 500/800. Ex. My last track date at Buttonwillow, toward the end of the day the rear the tires were starting to slide more than usual, so what I did was lower my compression one click down (-1) and it stopped and in IMO would have taken two to three clicks in the same direction w/ my CS. Again, that's just my opinion.

[JEllis]

OP,

If your mainly street with light track... go with KW CSs. I have had a lot of different coilovers over the rears. JRZ, Ohlin and Moton make a great product but then you have to decide on a make of springs, spring rate and camber plates. KW CSs have everything for you in a nice package. Its an easy way to upgrade to a full suspension setup with streetable camber plates (not noisy) without having to do much thinking. I am in love with my CSs.

I have TCK SAs on my E36... another great and inexpensive option but, again, you need to pick your springs rates and then camber plates. Most aftermarket camber plates are fully solid which brings some more noise into the cabin.

My two cents

[dogbone]

Originally Posted by bigjae1976

There is a range of adjustability that helps to fine tune. But the reason why you have had such good results is that you have springs that are properly matched to your damper. What a coilover like a JRZ does is allow higher spring rates than the TCK setup with pretty good koni struts. If you ran much stiffer springs and ran the adjustment down to the min or slowest adjustment the car would bounce your head off the roof.

The adjustments on the damper are NOT for comfort. Adjustments are for adjusting the speed of the shock. Turning it "down" is slowing the reaction of the shock which follows your observation of not following every bump and mouse turd in the road. The result might be more comfort but you're not going to run 1000lb springs on the front and expect it to ever be comfortable. Turn it "up" speeds up the reaction to put more weight on the tire and also reduce body roll (less weight transfer) resulting in more grip (probably not the best explanation).

Yes, of course, I am not saying that JRZ makes their damper to be a plushed-out pimp car. And let's be realistic----no one with a street car is going to run a 1000lb spring in the front. I hope there isn't a shop in the world that would recommend that. The point is that assuming a proper spring setup, the JRZ has a very wide range of adjustment, and the net result is that it can make the car very comfortable on the street, and still very track capable----something that jacobe92 seems to have just confirmed in his last post.

And it's worth noting, that the range of workable springs on the JRZ is pretty wide---meaning there's not only one recommended spring setup. I do not have aero on my car, but I do have a blower. I have experimented with three spring setups: 450/650, 600/650 and 600/800 (current). All of them work just fine, but require different damper settings. (fwiw, I think the ideal setup for an NA M3 with JRZ is 550/750. A blower adds more weight in the front plus the weight is even more accentuated because it charges into corners faster and has more nose dive while braking. Aero would require more spring rate to resist the additional downforce.) Plus, I have a nitrogen rig and have experimented with different nitrogen psi's in the remote JRZ canisters. I have found that I like higher psi's in the canisters. Factory default is 200 psi. I seem to like 300. (JRZ allows 100-350 psi. The nitrogen is in a bladder that presses against the oil, so the higher the psi of nitrogen, the more pre-set resistance the oil has against the road surface features. For me, the car feels like it's going roll less with a higher psi.)

I have enjoyed experimenting with my suspension setup. It's been a long road of learning for me. And by no means do I think I have it all figured out. But I'd guess I've experimented more than most. And the experimenting will continue when/if the car gets aero someday.

Regarding what JEllis mentioned, my friend recently bought a JRZ setup from EAS. It came with everything needed in the box---JRZ-brand camber plates, Eibach springs with rates recommended by JRZ (but you could request your own spring rates), and all other necessary bits and pieces.

[bigjae1976]

Originally Posted by dogbone

The point is that assuming a proper spring setup, the JRZ has a very wide range of adjustment, and the net result is that it can make the car very comfortable on the street, and still very track capable----something that jacobe92 seems to have just confirmed in his last post.

That's not an assumption that I'd make seeing the stuff people do on other forums. Google "Raceland coil overs E46" and you'll see why I do not make that assumption when this question is asked. Luckily it seems you have been spared from seeing this painful revelation in the BMW internet community.

I think we both agree the most important part is you are starting with a properly matched set of springs.

Originally Posted by dogbone

And it's worth noting, that the range of workable springs on the JRZ is pretty wide---meaning there's not only one recommended spring setup.

That's what you get for the extra $1000 over the TC Klines and is what I see as the major advantage over KWs. You can get the springs you NEED for your intended application. TC Kline does offer a range of spring rates but its not super long.

Originally Posted by dogbone

I have enjoyed experimenting with my suspension setup. It's been a long road of learning for me. And by no means do I think I have it all figured out. But I'd guess I've experimented more than most. And the experimenting will continue when/if the car gets aero someday.

That's what I saw as the drawback and is why I went with the TC Klines. Didn't want to nor do I think I have the skill or patience to play around with the suspension.

But some people love tinkering and don't want a canned solution.

Great discussion

[dogbone]

Originally Posted by bigjae1976

That's not an assumption that I'd make seeing the stuff people do on other forums. Google "Raceland coil overs E46" and you'll see why I do not make that assumption when this question is asked. Luckily it seems you have been spared from seeing this painful revelation in the BMW internet community.

I think we both agree the most important part is you are starting with a properly matched set of springs.

Yeah, for anyone reading this who's considering what to do, it's good to chat with a respected shop and also talk to people at the track. This platform has been around long enough now that good advice is pretty easy to find.

Originally Posted by bigjae1976

That's what you get for the extra $1000 over the TC Klines and is what I see as the major advantage over KWs. You can get the springs you NEED for your intended application. TC Kline does offer a range of spring rates but its not super long.

That's what I saw as the drawback and is why I went with the TC Klines. Didn't want to nor do I think I have the skill or patience to play around with the suspension.

But some people love tinkering and don't want a canned solution.

Great discussion

Yup, good thread! I may like my JRZs, but I've always heard nice things about TC Kline products. fwiw, I've met TC Kline twice at Laguna Seca. He avidly pounds his white E90 M3 around that track with stock power, his brand suspension and Hoosier R6. He's a good driver and a nice guy! It's nice to see a guy who makes a product, and then actually pounds on it himself. Actually, the last time I saw him there, he had a long trailer that also fit a Porsche, so he was switching between the two cars. Cool dude.

[Yaw]

I would not be put off by Ohlins' 20k mile rebuild cycle. My Ohlins are 10k beyond that and have dynoed fine, have seen others above 50k miles do the same. Any damper will need seal replacement in time, lifetime warranty or not. For rough road ride I do not think they can be beat in this segment. Ohlins also dropped their price recently as well.

[Hujan]

Been reading a lot about the JRZ RS1 lately and it really sounds like the ideal setup for me as someone who is looking to do 6-12 track days a year but who daily drives the car as well. Frankly, I'm not sure I have the patience or desire for complexity and like the idea of a single adjustment knob.

The only thing that has me stumped are all the options with the JRZs. Fixed height vs. coil over, spring choice, etc. My head is spinning and I am curious how most people are setting theirs up. In particular:

• Are you going with fixed height or a coilover conversion?
• If fixed height, what influences the ride height of the car? Is it purely a function of the springs used?
• What springs are most people running with these? From what I've seen, it seems JRZ recommends Eibach springs. Any others worth considering?
• What camber plates are people running with their JRZs?
• Aside from the dampers, springs, and camber plates, are there any other accessories or parts needed to run these on an E92 M3?

[FazerBoy]

I've also been thinking about going with JRZ RS1s.

Two questions:

- Can I retain the stock ride height? My car is a daily driver with some track work and most of my driving is urban, with ramps, potholes etc so I would not want to lower the car.

- My car has the competition pack with EDC. Will fitting the RS1s cause any error codes to be thrown and if so how do I deal with this?

Cheers

Jack