COILOVERS

[TANTO]

Street driven 92 (except when NSXPO comes to Mid-Ohio – please come back!!) Currently with Eibachs, stock shocks/bars/Daves rear beam/toes. Down under 2700lbs now and no complaints whatsoever but pondering unsprung weight/total weight reduction/improved handling with coilovers - KW3’s/Ohlins/JRZ. I see lots of great user experience on this site(thanks to all), but there has been some mention of noise/rattling/squealing with these units and wondering where this is coming from? Of course I understand compromises are required for performance. Considering the cost of these units plus the set-up, just want to know what to expect. And perhaps I could mitigate these noises with custom spring interface absorbers? Do helper spring set-ups have significant drawbacks on the street? Thinking I’m looking to get stiffness something like the OE “S”set up while maintaining my current 1 3/8” lower ride height and drop weight if sensible. Thanks!

 

[Honcho]

Street driven 92 (except when NSXPO comes to Mid-Ohio – please come back!!) Currently with Eibachs, stock shocks/bars/Daves rear beam/toes. Down under 2700lbs now and no complaints whatsoever but pondering unsprung weight/total weight reduction/improved handling with coilovers - KW3’s/Ohlins/JRZ. I see lots of great user experience on this site(thanks to all), but there has been some mention of noise/rattling/squealing with these units and wondering where this is coming from? Of course I understand compromises are required for performance. Considering the cost of these units plus the set-up, just want to know what to expect. And perhaps I could mitigate these noises with custom spring interface absorbers? Do helper spring set-ups have significant drawbacks on the street? Thinking I’m looking to get stiffness something like the OE “S”set up while maintaining my current 1 3/8” lower ride height and drop weight if sensible. Thanks!

All of the listed coils will deliver what you're after. I'd also add the MCS to the list- I love mine. Most of the squeaks from coilovers come from the use of spehrical ball top mounts, which are a race car setup using a nylon or metal ball sleeve to connect the shock to the body. Like any spherical bushing, they eventually start squeaking. Because race car. The KW, JRZ and the MCS can use adapters that fit the coilover springs and use the factory rubber bushings (read quiet). I got these from SOS. I'm not sure about the Ohlins.

My MCS uses a 8kg/6kg Swift 60mm spring setup with helpers, which is the spring rate of the NA1 NSX-R and S-Zero. They are silent. Any of these companies can set up the valving to work with the Type-S rates, which I believe are 6kg/5kg.



I've heard that the KW springs are noisy. Don't know about JRZ or Ohlins

 

[docjohn]

The long stroke ohlins are quiet like oem.

 

[TANTO]

Thanks guys, still studying the great legacy posts and will certainly use bushings up top (although those adjustable JRZ top mounts are SO sexy). Register MCS and LS Ohlins quiet- KW questionable. These helper spring set-ups are new to me and I was worried about those helper springs bottoming out every few seconds under load and making a slight impact noise. We old guys get a little testy about needing "helpers" he-he (pharma joke deleted). Stuntman comments about ride height/oversteer/front end loading under braking got my attention as well as Honcho's "driving style" valving. I remember a great test article where Mario/Danny Sullivan/others thrashed the car. Mario gave it a surprising compliment of "if you ask more of the NSX -it will give you more", Danny (who was a huge P-car guy) said something to the effect of "he would double" the front spring rate". Sounds like we may just have to run a stiff front end and live with it. Will likely get back with yous for proper shock/spring length down the road. So many expensive decisions (argh!). As a bit of an audiophile you may be familiar with the WAF (wife acceptance factor) that is always an important variable in our equation-he-he. Larry

 

[mwagner10702]

Don't overthink the coilover solution. Unless you track your car, most of the major players will have an out-of-the-box solution that will work. If you track your car, then IMO, MCS is the only solution.

There are two types of secondary springs, Helper and Tender.

Helper Springs:

In simplest terms, a helper spring is a short, very thin, flat wire spring that sits above or below the main spring. The main purpose of the helper is to keep the main spring engaged with its upper and lower seat at all times through full suspension travel. When the damper is fully extended, the main spring can unload completely and become free floating. When the spring is free floating it unseats from its locating rings.

Helper springs are very common on many coilover setups and have no effect on the overall spring rate.

Tender Springs:

A tender spring is a stiffer spring than a helper spring and does not fully compress at ride height but acts as part of a dual rate spring system. Under low loads, such as normal road driving, the tender spring is used to provide a softer spring rate than if only the main spring was used. Upon compression such as cornering situations, the tender spring closes up becoming inactive, allowing the main spring rate to take over and increase the cornering stiffness of the vehicle and provide a more firm, stable cornering platform.

 

[docjohn]

I can't wait for spring...

 

[TANTO]

Is there generally a plastic/rubber piece where the main springs meet the helper/tenders to keep things lined up and quiet? Would these come from swift? or from the supplier that would do the valving. I don't think i will have trusted local folks and will likely end up buying scales and doing the set-up myself. Love those MSC green anodized adjustment. TIA

 

[mwagner10702]

Is there generally a plastic/rubber piece where the main springs meet the helper/tenders to keep things lined up and quiet? Would these come from swift? or from the supplier that would do the valving. I don't think i will have trusted local folks and will likely end up buying scales and doing the set-up myself. Love those MSC green anodized adjustment. TIA

What you are referring to is a stacked spring adapter. These are available from a variety of sources including the spring manufacturer.



This example is from Swift, which BTW makes a great coil spring. Probably my choice over Hyperco or Eibach (I've used all three).

 

[stuntman]

Pretty much every "helper" or "tender" spring is fully compressed at ride height. "Tender" spring rates are almost never high enough to not be coil bound at ride height.

 

[Arkaid]

KW's aren't inherently noisy unless you introduce something into the system between the spring and the top mount, i.e. an air cup or the like. The KWs come out of the box with their own adapter between the helper and the main spring already, so it's a fully plug and play system with the OE top mount which is nice, and the rates are 6kg/6kg out of the box. No more noisy than MCS or Ohlins and certainly quieter than my JRZs with the pillow ball top mounts were.

You don't want a softer spring rate of front - too soft of a spring rate up front relative to the rear could induce the car into a more oversteer-prone nature. Unless of course that's your thing, and one which I always found interesting about the JDM coilover setups (Tein, Aragosta etc.) - maybe our Japanese owner contingent likes to go sideways more than we US owners do

I like the KWs because of the R&D input that went into them - the V3's on the NSX are the best KW system I've driven on. For the price I still think it's the mid-tier coilover to beat.

 

[stuntman]

The KW V5 is a top tier contender with some aspects that best most of the competition.

 

[mwagner10702]

The KW V5 is a top tier contender with some aspects that best most of the competition.

They do look compelling. Not sure they are the right solution for a street driven car.

New in! KW V5 coilovers for the Honda NSX and Acura NSX

In contrast to common mono-tube or twin-tube dampers, we trust in our Solid Piston technology for the KW V5 coilover kit for the modern Honda NSX / Acura NSX. This way, our damper hydraulic is able…

blog-int.kwautomotive.net

$6,499

 

[stuntman]

They do look compelling. Not sure they are the right solution for a street driven car.

$6,499

The "right" solution for a street driven car will be different for each individual person. For some, stock suspension is the best solution. When it comes to high quality, premium coilovers, the V5 has an incredible ride, and delivers performance, technology, and 4-way damping adjustment for similar or a lower cost than many of its 3-way competitors. There's not many NSX dampers out there with solid piston technology.

 

[TANTO]

Appears we have at least three top shock folks (MCS/KW/OHLIN). I'm a little bummed in that helpers/tenders are needed - assuming to be able to use off the shelf race springs which is certainly an understandable necessity for the track. I'm thinking Ideally (for the sake of simplicity/noise) a vendor would have custom springs wound for the application which would not need tenders. 20 years ago you could get someone like Eibach to make springs to your spec for not that much cash - oh well times change and matching those "home made" springs to the valving is likely asking for big trouble. So swift race springs it is 8/6 - 6/6 -6/5 and i'll have to mull over the shocks and hats perhaps selecting by ease of getting to the adjusters. Those V5's are gorgeous. Regarding suppliers - that would be Sakebomb only for the Ohlins - how about most knowledgable suppliers for MSC and KW? Don't care about installers. Thanks guys!

 

[stuntman]

KW is KW. You don't have to deal with a middleman determining the dimensions or valving.

Helper/tender springs are almost never a cause of noise. I would not be turned off by them.

I would add JRI dampers from Ultimate Performance to that list. 2-way adjustable motorsports dampers:

ULTIMATE PERFORMANCE ACURA NSX COILOVER SHOCKS - Ultimate Performance

Ultimate Performance Acura NSX coilover shocks are double adjustable and tuned specifically for road racing and autocross competition.

upspeedshop.com

JRI was founded by Jeff Ryan, the guy who started Penske Racing Shocks and started his own damper company with new valve designs. JJ at UP is an amazing guy. Extremely knowledgeable and his support is first class. Support and knowledge is everything when it comes to buying motorsport dampers from a middleman (which is the only way for most of these dampers).

These are my FD RX-7 JRI (double-adjustable) Coilovers:

 

[mwagner10702]

. . . how about most knowledgable suppliers for MSC and KW? Don't care about installers.

If MCS is your end game then I would recommend you contact AR Motorsports. They are well versed in the MCS universe and use them on all their race cars. They installed a set of 2WR dampers on my NSX and supplied @Honcho with a set of 1WNR.

AR Motorsports

www.ar-motorsports.com

 

[Arkaid]

KW is KW. You don't have to deal with a middleman determining the dimensions or valving.

Helper/tender springs are almost never a cause of noise. I would not be turned off by them.

I would add JRI dampers from Ultimate Performance to that list. 2-way adjustable motorsports dampers:

ULTIMATE PERFORMANCE ACURA NSX COILOVER SHOCKS - Ultimate Performance

Ultimate Performance Acura NSX coilover shocks are double adjustable and tuned specifically for road racing and autocross competition.

upspeedshop.com

JRI was founded by Jeff Ryan, the guy who started Penske Racing Shocks and started his own damper company with new valve designs. JJ at UP is an amazing guy. Extremely knowledgeable and his support is first class. Support and knowledge is everything when it comes to buying motorsport dampers from a middleman (which is the only way for most of these dampers).

These are my FD RX-7 JRI (double-adjustable) Coilovers:

View attachment 196472

Those are sexy...dang!!

 

[TANTO]

From their website anyway It appears like you do have to go thru a dealer for KW (they list 93 US dealers!) As i do hear everyones great advice about working with folks who have done this valving/spring selection thing for this actual car, I'm wondering who might even have hands on knowledge yet? I assume the extensive V3 work they did will only "roughly" transfer to the V5. Or maybe they are all valved in Germany so the dealer really doesn't matter except for spring choice? I realize these V5 units are overkill/perhaps difficult to dial in for my mostly streeter as well as likely needing to keep those fancy "hard" top hats to get the benefit from that solid piston valve tech, but those alum bodies would likely save one at least a few oz's per/wheel he-he. And thanks for the UP tip, they look very nice also! Thanks!

 

[stuntman]

KW is engineered, tested, and valved in Germany by their engineers and with a 4-post "shaker rig". They develop the kit and then their dealer network will sell them to you. Very few dealers will offer a service to swap out the spring rates for you (which you can do yourself or your local shop who can install them), but pretty much none will change the valving.

I've worked with them on the V3 way back in the day and have given them feedback on their new 4-way adjustable "V5". The V5 is part of the "newer era" motorsports damper design, which has gone from a mono-tube damper to a twin-tube (Just like the Ohlins TTX and Multimatic DSSV dampers) with a solid piston.

My V5s were amazing out of the box and I have not strayed far from the baseline settings. I will make a thread with recommended settings for the V5 like I did for the V3 so people won't get lost and have a couple settings to try or stay close to, if they want to play with the shocks and dial it in for what they like.

When it comes to motorsport dampers like Ohlins, Penske/JRI, JRZ/Moton/MCS/AST, etc..., the fitment and performance will almost always comes down to who built the shock, determined the physical dimensions and valving. This is far more important than which company's valve design is theoretically better.

In most cases, there will be a separate shop or company or person that deals with a given manufacturer and will either order individual parts and assemble the dampers and then sell them to you as a customer, or will specify the valving and assembly lengths to the manufacturer, who will then build the shocks for them that they will then sell you. Most of these motorsport damper companies do not do their own development to offer a product for a given car.

So you need to ask "who is doing the development?" -It's the people/shops that sell these motorsport dampers. How many have they sold? How many customers track or race the NSX? -call of this is gained experience by a company offering Damper "X" for them to listen to feedback and complaints, to refine and "develop" the damper package that they sell. Pretty much any of these shops can build a damper for any car, once they get the dimensions of the stock shock, but dialing in the travels and dimensions to avoid tires hitting the inner fender liner, dialing in the damping for the best handling and ride quality for that platform has a learning curve and you don't want to be paying to be a guinea pig.

Eric Messley was the go-to NSX Penske guy. JJ Furillo does great work with JRI dampers (the company that was created after the head Penske damper designer left Penske) and makes JRI dampers for the NSX. I'm not sure who the current go-to shop is for JRZ/Moton/MCS for NSXs. I'm not sure what Nitron's background is with the NSX platform or who helped with that development.

The difference between unsprung weight of aluminum vs steel is insignificant. Noise from spherical bearing top hats will vary depending on the quality of bearings used by different shops, but many are quiet.

 

[RyanRA]

My V5s were amazing out of the box and I have not strayed far from the baseline settings. I will make a thread with recommended settings for the V5 like I did for the V3 so people won't get lost and have a couple settings to try or stay close to, if they want to play with the shocks and dial it in for what they like.

This, I like

 

[TANTO]

Fantastic post Stuntman! May have to violate your "pick the tires first" rule he-he as my current Falkens are likely an interim pick. Called KW main US office and Sakebomb CA. The KW guy Ron who said that he was the man on all US stuff was a little stiff (pun)asking me for part numbers (?) When I named dropped that Billy Johnson had been supportive of their products on our site - he didn’t know who Billy was (!) – must be a new hire/bean counter. Not a great call but I won’t hold that against KW Germany. I think we pretty much know everything regarding the V3’s already so that was not a real negative. Since I spoke of the alum bodies on the V5, I should say that a different KW dealer did state that the V5 units were slightly heavier than the V3 because of their more rugged race level superior valving – of course saving OZ’s at the expense of superior performance is silly. Spoke with Heath at SB CA who was well versed on their product. Stated they had sold over 150 sets of first gen NSX kits and that the car was “four posted” long ago at their CA lab which is the Ohlins factory west coast lab facility. They buy the bodies only from Ohlins and apparently make or source the valving parts and then assemble there. They can rebuild although he stated that on the street they should be good for 80k or so. Further stated 90% of their street sales were the “GT” 8/6 package. They do use Swift springs and say that the units valving would be good for going up or down 30% for a spring change, although he stated it unlikely that I would want to go down in rate. As expected he did not recommend using the OE top hats as they have not been specifically tested with their DFV technology. Post not meant as a comparison of these two units mentioned and no specific takeaway for me – I’ll close my eyes and pick one when I see the ice melting. I did find a KW dealer that does discount the KW’s, both V3 and V5 which would net around $2850 for the V3 and $5900 for the V5. No price break on the Ohlins at $4250. Which ever one - Get-em now before the “damper tariffs” kick in – he-he. Been re-reading a couple of VERY old (1980’s!) books that seem possibly still relevant(?) – ENGINEER TO WIN-Caroll Smith & HOW TO MAKE YOUR CAR HANDLE –Fred Puhn. Again “so” thanks for the “up-to date” posts of our members

 

[stuntman]

I'm sorry to hear you had a bad experience calling KW. Ron is just a phone tech. Next time ask for Chris Marion and he will get you squared away.

The KW V5 part number is: 30950022

Engineer to win and Tune to win are good books to have on the shelf. They're easy to read and his writing is entertaining. There's a good bit that's out dated but the fundamentals are what matters. Racecar Vehicle Dynamics by Miliken is far more complex but is the bible for the subject and good to have on the shelf.