NSX-R Suspension Question - Can it be modified?

[Nero Tenebre]

So I thought I would ask the suspension gurus out there about this- I have the 02 type R suspension (springs/showa dampers) and my question is: Is there a way to lower the rear?

The performance is fantastic but I am a little bothered by the high ride height in the back and the uneven fender gaps. My usage is mostly street, occasional track. I realize that the front springs are stiffer so that's why they were able to lower the front more and the rears are a bit softer and so they are longer to allow for more travel. I am just talking about lowering it 1/2"-1" in the rear and the idea I had was to swap out the rear springs for slightly shorter springs with the same or similar spring rates. That way I would still keep the showa damper with the external reservoir and the fast reacting performance it brings when I can live with a little less maximum travel.

Next question would be, does anyone know what I could replace them with to properly fit and match the rate. Or what other factors I should consider in attempting this? I realize that I will need an alignment but I don't think it will take me to the level of needing a camber kit.

 

[Nero Tenebre]

It's been a few days, no one has any input?

 

[docjohn]

the short answer (get it) is the shock length is matched to the spring height so replacing the springs for shorter ones would change the damping curve, but for street driving it may not be important; as to springs I'm sure that swift/eibach ect have whatever length you need.

 

[NSXDreamer2]

Get yourself a pair of big subs with a big box or couple of dead bodies in the trunk if you don't care about the performance and the dynamic balance of the R suspension...:biggrin:

I for once would suggest you sell the R suspension as they have very good resale value and nsx owners think highly of it. (i don't) and get a coilover like K Sports or Tein. or yellow Koni with ground control coil over.

on a more serious note, my cousin has the R suspension on for more than a few years, and the ride height is spot on and they don't have the rake you talk about. (which by the way, the rake is more preferable for nsx that has stiffer front springs, and that's how i set up the car with and more than a few reputable nsx shop/builders would suggest.)

 

[docjohn]

dreamer makes a great point.The R susp is likely not the susp for your needs,it will sell,and you can get an adjustable (coilover) system for cheaper.Some folks on prime are really likeing the BC setup.

 

[Nero Tenebre]

Well dont get me wrong guys- I love this suspension or I wouldn't bother asking how to modify it. Just bc I said I'm mostly street duty and this is the track forum doesnt mean I should get some soft coilovers for a more compliant ride and ability to customized ride height. I want my performance and have been unimpressed with coilovers while the R suspension has the firmness and lightning reflexes I am after. Just because I don't like the pre-set ride height and want to tailor it to my liking doesn't mean I want to put weight in the rear. If you look at my mods you will see I care a lot about performance and I have a very quick NA car with all the track essential non compliance stuff, chassis reinforcement, weight reduction, etc and have a balanced mod sheet. I am just looking for some knowledgable people to help me explore this option in depth. I am going to look into your earlier point Doc, if you can think of anything else please share! I bet if i did only 1/2" it would not have a large effect. Thanks to both for your input btw.

 

[HBui39]

well if you like how it feels, reducing rear shock travel and changing the suspension geometry is not ideal for performance. however, with linear springs, it is possible to cut them without ruining them... just be careful not to heat them up too much or you may change the properties of the metal.

 

[ANYTIME]

Well dont get me wrong guys- I love this suspension or I wouldn't bother asking how to modify it. Just bc I said I'm mostly street duty and this is the track forum doesnt mean I should get some soft coilovers for a more compliant ride and ability to customized ride height. I want my performance and have been unimpressed with coilovers while the R suspension has the firmness and lightning reflexes I am after. Just because I don't like the pre-set ride height and want to tailor it to my liking doesn't mean I want to put weight in the rear. If you look at my mods you will see I care a lot about performance and I have a very quick NA car with all the track essential non compliance stuff, chassis reinforcement, weight reduction, etc and have a balanced mod sheet. I am just looking for some knowledgable people to help me explore this option in depth. I am going to look into your earlier point Doc, if you can think of anything else please share! I bet if i did only 1/2" it would not have a large effect. Thanks to both for your input btw.

Maybe the weight reduction is making the car sit higher? Just a thought

 

[TURBO2GO]

The bottom line is that the NSX-R suspension sells for a lot of money, because people think that "OEM is best". If you do anything to it, it is no longer OEM and you will have a real hard time selling it. I just don't see the point. There is nothing about that you can't achieve the equal to ot better than with something else for the same price AND get your lower ride height. I just wouldn't modify it. I am with the other guys. Sell it.

 

[Nero Tenebre]

I'm definitely not planning on cutting the springs, by modifying it I mean that I would swap in a different spring that was properly matched to it's settings. Taking the spring off the damper is reversible so it would not be a permanent modification. It may not be worth it in the end due to the complexity of suspension design, but I'd still like to understand more about its effects which will at least give me more knowledge.

 

[HBui39]

you can probably source a set of NSX-R springs somewhere to cut up. other spring options are simply going to be too soft in comparison. doing a custom one-off is simply cost prohibitive. there isn't even room to set the perch lower on the rear like a bilstein.

 

[nsxot1c]

I'm definitely not planning on cutting the springs, by modifying it I mean that I would swap in a different spring that was properly matched to it's settings. Taking the spring off the damper is reversible so it would not be a permanent modification. It may not be worth it in the end due to the complexity of suspension design, but I'd still like to understand more about its effects which will at least give me more knowledge.

I would definitely do this. Order up a set of aftermarket springs and even if you just use the rears to achieve the ride height you want, you could easily still swap them back later on and also sell all of the R suspension down the road with oem R springs. For as cheap as ~$300 you could achieve exactly what you're looking for and be able to not have to order an entirely new suspension system, and swap everything in.

Just swap in the rear springs and you'd be all set. I'd go with H+R if it were me, great performance springs. But Tein and a few others also sell springs. I'm quite sure with a little research you could find spring rates to match the R rear springs as well.

http://www.ebay.com/itm/H-R-LOWERIN...NSX&hash=item4d0027abc1&vxp=mtr#ht_2835wt_904

 

[TrustJDM]

according to Dali's site, H&R and OEM NSX-R is worlds apart on spring rates. I highly doubt they pair up well. Also the H&R slam the car so you will have a very odd look w/the rear slammed & the front lifted.

If you had coilovers then it's easier to mix/match spring rates. I would go with the suggestion to contact SWIFT as well and see what they have close to the NSX-R's rates. Perhaps something from another vehicle & have it cut to the ideal number of coils for the NSX assuming it is a linear spring.

http://www.daliracing.com/v666-5/catalog/suspension/more_springs_matrix.cfm

 

[Nero Tenebre]

Now we're getting somewhere!

 

[davidsk]

I seem to recall reading that the NA2R suspension was a progressive spring. I don't see how you can pull off what you're talking about doing unless you can find someplace that will make you a spring that has the ends made to fit the factory perch and hat. I'd say I'm another vote for going after a good coilover setup if the height bothers you that much. People seem more than willing to pay top dollar for the R suspensions.

 

[Tangoman]

On top of that, you're talking custom springs at this point.

Cutting down a spring might change the height, but it also changes the stiffness. So, the likelyhood of some spring maker finding something they already have that will give you the ride height you want and the stiffness you want while using the dampers you already have?

Yea, try again.

Coilovers is the way for you to go if the ride height bothers you. And you should ask the question - "why does my NSX-R suspension setup have uneven fender gaps front/rear?" I don't remember the NSX-R having this issue...

 

[Honcho]

I would not modify your NSX-R suspension. The problem with changing springs or cutting (eek!) springs is the NSX-R suspension was designed and fine-tuned as a system. Altering the characteristics of the spring rate and ride height will at best yield inconsistent handling and at worst create a downright dangerous car. After all, while we know the max spring rates, the R springs are progressive and we have no idea what the range is. Trying to guesstimate while seeking a perfect fender gap is not a good plan, since the damper curves are tuned to the OEM springs. Remember, changing ride height will affect camber and toe, which can have bad consequences on a rain-soaked highway on-ramp, for example.

If you are unhappy with the ride height, you should invest in a coilover setup that will permit height adjustment. You can sell your NSX-R for a good price and then go to a KW V3, which will give you the same performance as the R, but lets you adjust height to your preference. Or, for about $1,000 less you can go to the BCR system, which I have on my NSX. I ordered a custom setup with Swift springs specifically to replicate the balance and performance of the NSX-R. With the suspension aligned and set to NSX-R height, I cannot tell the difference between the BCR and NSX-R (having driven one), other than my BCR rides much better. In truth, the BCR probably will not last as long as the NSX-R, but it is much easier and cheaper to replace as parts wear out than the NSX-R.

My two cents.

 

[Nero Tenebre]

Thanks for the input honcho- I thought you still had the R setup. I think your new setup may ride better bc it's slower to react though? The R setup is very bouncy but it's bc the external oil reservoir aids in fast response I believe. If the springs are progressive then that's a game changer and it looks like it's not worth messing with. As for substitutes I would like to hear more about your setup and the similarities. I was thinking JRZ coilovers, I have KW on my other car and they are nice but too soft.

 

[nsxot1c]

Thanks for the input honcho- I thought you still had the R setup. I think your new setup may ride better bc it's slower to react though? The R setup is very bouncy but it's bc the external oil reservoir aids in fast response I believe. If the springs are progressive then that's a game changer and it looks like it's not messing with. As for substitutes I would like to hear more about your setup and the similarities. I was thinking JRZ coilovers, I have KW on my other car and they are nice but too soft.

After more input I'd agree on this as well. Apparently matching the NSX-R spring rates seems difficult and therefore going with a coilover setup may be a better idea. This is why NSXPRIME is so great!!

 

[Hapa88]

however, with linear springs, it is possible to cut them without ruining them... just be careful not to heat them up too much or you may change the properties of the metal.

This is not true. Cutting the springs will increase the spring rate. This is because the "number of active coils" will decrease given the spring rate (k) equation:

spring rate = (modulus of spring steel X wire diameter^4)/(8 X number of active coils X mean coil diameter^3)

 

[Honcho]

Thanks for the input honcho- I thought you still had the R setup. I think your new setup may ride better bc it's slower to react though? The R setup is very bouncy but it's bc the external oil reservoir aids in fast response I believe. If the springs are progressive then that's a game changer and it looks like it's not messing with. As for substitutes I would like to hear more about your setup and the similarities. I was thinking JRZ coilovers, I have KW on my other car and they are nice but too soft.

My full review is here. An interesting anecdote from my research was an engineer from JRZ came into one of the BC discussions over on NASIOC and commented favorably on the design. He said that while they serve two different market spaces, the fundamental BC design was very good and he was impressed. He did comment that the shock valving would not be as refined as JRZ or other motorsports-level dampers, which would be a limiting factor for ultimate performance. The real world data bears that out, as the Type BR system is about 2 to 3 seconds slower per lap than a full-up triple adjustable race suspension.

As for comparisons to NSX-R, I find no difference in the "reactiveness" of the suspension. I have the 10kg/8kg kit designed to mimic the NSX-R balance. If anything, the BC/Swift combo feels more linear than the NSX-R I drove in transitions and more planted in cornering. With the dampers turned up to 25 F 20 R (0=soft 30= stiff) it handles like a go kart. I should be taking it to the track in a few weeks and will report back. Based on the damping profiles of both systems, my driving impressions, and the track data, I think the NSX-R will edge out the BCR at the top 10% of the performance envelope. The NSX-R valving is just better, period. For the rest of the 90%, the BCR is better. More comfortable, good performance, predictable sharp handling, and adjustability both in height and damping. If your car is a track rat, keep the NSX-R. If not, the BC is worth a look.

 

[NSXDreamer2]

since we are in the track forum, I can tell you it's big misconception of harsher suspension meant more heavy duty thus it will be great in glassy smooth road surface like a race track. (Above assumptions and beliefs are all wrong).

The very best suspension out there is the one providing the control and traction for your car while it still soaks up the impefections from road surface. The nsxR suspension is quite great on track, but they are not the best, especially street driving.

can you take a picture so we all can see what you meant regarding the ride height ?? as more than one member (including my cousin's nsx.) mentioning that nsx R suspension have an pretty even wheel gap between the front and back.

 

[Nero Tenebre]

I should be taking it to the track in a few weeks and will report back.

Thanks for all the info, let us know how it fares at the track.


Here are some photos- often get comments about the raked stance.

Old photo with OEM wheels:

DSCN1027 by Nero Tenebre, on Flickr

Then Tecno wheels:

[/url]
DSCN2337 by Nero Tenebre, on Flickrww.flickr.com/photos/70274025@N00/7690940168/]

[/url]
DSCN2323 by Nero Tenebre, on Flickr

IMG_4592 by Nero Tenebre, on Flickr


and currently with a slightly taller 275/35/19 rear tire:
[url=http://www.flickr.com/photos/70274025@N00/7667188168/]
P7140108 copy by Nero Tenebre, on Flickr

 

[Hapa88]

Do you have your front spare in? If so, might want to look at removing it, that might bring the front up a little..

 

[Nero Tenebre]

I did with the stock wheels in but since I got the bbk I took it out. I don't think it made a difference but it looked lower with the smaller front tire I think.