Suspension Experts - Rebuilding Konis

[Honcho]

My search for a good used NSX-R suspension has now gone for almost 4 months and nothing has turned up. It is possible I might not find anything, so i need to consider other options. My budget is $1500, which is about what a nice used NSX-R set was going for last year. Here are my options as I see them. Any advice/comments would be welcome.

Option 1: Revalve current Koni Yellows to NSX-R spec and use OEM NSX-R springs.
Option 2: Purchase new Bilsteins and revalve to NSX-R spec and use OEM NSX-R springs.
Option 3: Purchase new Type-S suspension from Honda (I am concerned it will sit too high)
Option 4: Purchase used NSX-R (NA1 or NA2) suspension from Japan- anyone know if this is even possible or worthwhile? I am considering it because I’m sure there are a lot more used suspensions circulating over there than here in the US.
Option 5: Purchase entry-level coilovers (I am concerned about quality and I don’t need the adjustment options)

Assuming I go the rebuild and revalve route, does anyone have ACTUAL shock dyno data for the NSX-R suspension (not just the Honda published numbers)? I ask because GoldNSX went this route with his Bilsteins and advised the result was not the same as the OEM shocks. Also, I’m not interested in the KW V3 mostly because it is outside my budget (see above) and also because I have driven an actual NSX-R suspension back-to-back with my current Comptech/Koni and I am satisfied with the ride quality.

 

[BATMANs]

Last time I spoke to Koni they said that they can do some trick valving to emulate the KWs for $275 each

 

[RYU]

Honcho, I really like Option #2 but before I commit. A few questions if you don't mind.

1. Are the Koni shocks rebound adjustable?
2. I can't recall if you track your car or not.

I know you're expecting some of the suspension experts on here to chime in so Please Do gents!

 

[Mac Attack]

I propose Option 6:

Wait until NSXPO is in your area relatively soon and then proceed to ride in as many NSX's as you can to get a sampling of all the choices.

As much thought and time you've spent on this, what's the harm waiting a bit more?

Dave

 

[BATMANs]

Honcho, I really like Option #2 but before I commit. A few questions if you don't mind.

1. Are the Koni shocks rebound adjustable?
2. I can't recall if you track your car or not.

I know you're expecting some of the suspension experts on here to chime in so Please Do gents!

1. yes for just the yellow
2. Nope. just street racing

 

[Hrant]

Another alternative is the Comptech Pro which uses Koni shocks. I keep getting impressed with this suspension. With the cold weather we have had and progressively worse roads, I just adjusted the damper with one less stiff setting and it almost like an OEM ride now. For track, it would be 3 settings stiffer and done - no hassle with twenty marketing sales pitch adjustments.

 

[Honcho]

Last time I spoke to Koni they said that they can do some trick valving to emulate the KWs for $275 each

I have heard the same thing. But, I want to replicate the NSX-R, not the KW.

Honcho, I really like Option #2 but before I commit. A few questions if you don't mind.

1. Are the Koni shocks rebound adjustable?
2. I can't recall if you track your car or not.

I know you're expecting some of the suspension experts on here to chime in so Please Do gents!

1. Yes.
2. Yes. 80% street 20% track. Figure 5 track days per year at HPR, which incidentally is the track for 2012 NSXPO.

I have two concerns about the Bils. First, GoldNSX tried to match a set of Bils to the OEM Type-S. He used the published data and had them re-valved. He was dissapointed in the result, which was not accurate to the OEM. He eventually scrapped the project and went to KW, and then went back to Bils valved to KW specs based on actual dyno data. I don't want to repeat those mistakes. Second, I have heard the Bils high-pressure monotube design is not as durable as the low pressure twin-tube Koni. FWIW, the NSX-R is a low pressure twin-tube shock.

I propose Option 6:

Wait until NSXPO is in your area relatively soon and then proceed to ride in as many NSX's as you can to get a sampling of all the choices.

As much thought and time you've spent on this, what's the harm waiting a bit more?

Dave

Dave I have already driven most of the options. I like the NSX-R. My issue now is one of access- I simply can't find a used one. In 2010-11, 4 nice low mile sets sold for less than $2k each. Now, nothing. :frown: That's why I'm asking about Japan. There have got to be dozens available used.

Another alternative is the Comptech Pro which uses Koni shocks. I keep getting impressed with this suspension. With the cold weather we have had and progressively worse roads, I just adjusted the damper with one less stiff setting and it almost like an OEM ride now. For track, it would be 3 settings stiffer and done - no hassle with twenty marketing sales pitch adjustments.

I have heard the Comptech Pro mounts clunk. Plus, I've never seen a Pro for any less than $2000. That's $500 over my budget. Mrs. Honcho will say HELL NO.

 

[RYU]

Just throwing this out there but perhaps SoS or Dali will let you rent the shocks just to dyno test them. I know that will likely put you over your budget but I see that as being a last resort option. It seems difficult to replicate the behavior of a shock without them.

I'll tell you though, if you're able to lock down the specs of a NSX-R shock set and it can be duplicated with a set of Konis or Bils you can probably spread out the cost of the R&D with a few other prime members who would be interested in a group buy.

 

[Scin]

My vote is for option #2, Bilstein makes an excellent shock.

I agree with avoiding cheap coilovers.

 

[Mac Attack]

Second, I have heard the Bils high-pressure monotube design is not as durable as the low pressure twin-tube Koni. FWIW, the NSX-R is a low pressure twin-tube shock.

FYI - Around the 2002 timeframe, Showa had a bunch of QC issues from an owner change or something like that. When I was researching these before I bought my setup, I found a few cases of the 2002+ NSX-R dampers failing. Just something for you to investigate on your own and be aware of.

Dave I have already driven most of the options. I like the NSX-R. My issue now is one of access- I simply can't find a used one. In 2010-11, 4 nice low mile sets sold for less than $2k each. Now, nothing. :frown: That's why I'm asking about Japan. There have got to be dozens available used.

From what I gather, you are methodical, do your research, and seem to prefer OEM over other aftermarket alternatives. In that case, and from what you've said above, I would wait until a set comes along. Otherwise, you'll probably always wish you had!

The NSX-R suspension isn't for everyone because of the stiffer ride. Maybe try tracking down some owners and ask if they'd consider selling. Or start frequenting the Japanese auctions.

Hope you can find a set :smile:

Dave

 

[angus]

My two choices for you would be:

A) #2 Bilstein is never a bad choice, it's on 4 of my own cars.

B) #5 - some of the stuff out there is actually very high quality these days, I have run (and still do) Megan and K-Sport without one single issue.

 

[Honcho]

Well, the consensus seems to be a custom Bilstein NSX-R suspension! Let’s just call it the “Hybrid”. That opens up a few questions:

1. I want to ensure the Hybrid sits exactly the same as NSX-R. Is the NSX-R spring on the top perch the same height as on the top perch of the Showa shock? In other words, are the top perches the same height and are the two shocks the same overall height from the center point of the lower bolt to the perch? My nightmare is putting the NSX-R springs on the Bils and having it look like a 4x4.

2. Shock tuning. Given GoldNSX’s experience trying to recreate OEM on the Bils, I want to make sure this is done right. I think it is more than just giving Bilstein the spring rates, isn’t it? I have some NSX-R shock data at 0.01, 0.05 and 0.3 m/s. Should I give them that too? Or, is it better to trust the shop’s expertise and say here’s my car, here’s my springs- make it work the best way possible? What data should I give to the shock builders?

3. Mounting hats. What 21-year old bits should I replace in here? Bump stops?

Thanks guys

 

[Hrant]

There is definitely a novelty/satisfaction in designing something to meet one's specific needs. I have fallen into that mental mindset several times just because I wanted to know, test, .... or didn't know!

Frankly, suspension is one area where I think by the time you do your R&D and consider all the time/costs and possible frustrations, you may realize that there are already quite attractive off the shelf solutions for you. As others noted, The NSX-R is jarring enough that it will help you pass kidney stones - but then again I assume you know this.

Yes the Comptech is a bit expensive - and there is a reason for that! They work and are as competitive as some of the other high end ones. Perhaps over your budget. But occasionally they show up for $1800. And since those are made to order, or if u are buying a used one, check or have the bearing upgraded to MIL spec-8 if the used ones are clunking; but not all do.

 

[Honcho]

Hrant I totally get where you're coming from, but if I wait for a Pro to turn up, I might as well wait for a NSX-R since they are equally rare in the marketplace. I think my best bet is to trust that Bilstein understands how to valve their own shocks correctly. I may just give them the spring rates and tell them to make it the best possible.

 

[angus]

I may just give them the spring rates and tell them to make it the best possible.

Will they do that? The last time I sent shocks in for re-valving at Bilstein, they wanted actual numbers, they do not want to do any figuring out, that way it's your problem I suppose.

 

[RYU]

How do the internal shock pressures come into play?

 

[Honcho]

Will they do that? The last time I sent shocks in for re-valving at Bilstein, they wanted actual numbers, they do not want to do any figuring out, that way it's your problem I suppose.

The guy I talked to said they just need the spring rates, but if I had shock dyno numbers for the NSX-R they could take that into account too. From further research, I've found that Bilstein performs a "rough" revalve:

From Fat Cat Motorsports:

Revalve/rebuild? Can accept a very low-mileage 06+ MX5 or 04+ RX-8 Bilstein HDs but prefer to start with brand-new. You achieve better performance and longevity if we revalve new HDs whether shock-only or as part of a complete coilover package. Revalve cost is $150 per shock and we shape the entire damping curve based on vehicle + passenger weights, driving style and your typical roads. Bilstein revalves are less refined than what we perform based on our modeling and detailed consulation process

This may explain why GoldNSX failed to replicate the Type-S feel in a Bilstein?

How do the internal shock pressures come into play?

A shock damper curve is not linear. Most shocks start out somewhat softer at low speeds and as the speed increases the damping increases. The trick to getting a Bilstein to feel like a NSX-R is to match the entire damper curve. Problem is, we only have NSX-R data at a few points along the curve. The rest is guesswork, unless someone puts their NSX-R shock on a dyno and publishes the results!

As luck would have it, I have a potential line on a NSX-R suspension. I'll let you guys know if it works out.

 

[Honcho]

Brief update. NSX-R went nowhere. Vance talked me into buying a Type-S instead lol.

 

[docjohn]

If it makes you feel any better ,at xpo you can get a ride on track with me and compare it to your type S.

 

[Honcho]

Uh oh ... just got off the phone with Tim at Acura and- cue doomsday music- THE ZANARDI SUSPENSION IS DISCONTINUED!!!

Tim even checked with Honda Japan, who checked with Showa and they said "We are done. There are no more." Great- my JDM quest is looking futile! What to do????????

 

[docjohn]

cold call some of the bigger dealers who moved nsx,esp a zanardi or two and see if they have a set of at least the springs.Imho the Z springs matched to the standard koni yellows was pretty good.

 

[stuntman]

Internal shock structure and design greatly influences or limits the damping characteristics of the shock. Therefore you might not be able to get a koni or bilstein to be valved like the nsxr.

 

[Honcho]

Billy can you PM me, your box is full.

 

[stuntman]

email me at: [email protected]


Billy

 

[Honcho]

Anyone know the stock rake for the NSX-R suspension? I am setting up my new coilovers using Billy's suggestion of making the coil heights the same L to R in order to get the right cross-weights, but I want to set the rake correctly as well. Spring rates are the same as NSX-R: 10kg/8kg. Sways are RM Racing solid 19.05 mm front and rear.