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Need some guidance on suspension set ups

How are you adjusting the ride height? Do you raise the threaded spring perch or the lower threaded body? Can you take your wheel off and take a picture of your damper to show where your spring perch heights are?
I can later on. The spring is set to 4mm of preload as seen on BC YouTube video. Height is adjusted from the shock body.

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BC on full stiff? How could you expect that to work well. It will be highly overdamped. I get that you're doing it in an attempt to solve another problem but it will add a new problem in doing so.

And, in my view, ridding in a car with KW makes one realize that there is room for improvement in the OEM dampers.
Right now my settings are 25. 5 away from full stiff. I have gone through just about every setting on these coil overs and ever single setting is bouncy. I like 25 though, as it seems to be the least bouncy. Oem replacements should arrive soon.
 
Is this the BC video you followed for setting the preload?

https://www.youtube.com/watch?v=HlqOA35NmAw

*This is a POOR method. You really need to measure the height from the top of the spring perch to the bottom of the spring perch and make sure the right and left sides are even -before fine tuning on a set of scales to corner balance the car. The method above can lead to significant differences right to left because the 'snug' setting is extremely subjective and could be 2-3 turns different from side to side. I'm surprised BC posted this video. The NSX scales very well and i've had crossweights withing 0.2% by setting the right and left sides the same length, and 2-3 turn differences could easily swing the cross weights beyond 0.2%


For the NSX, BC's appear to have very little total shock travel which can bottom out in both compression as well as rebound (droop travel, shock extension). It also appears the BC coilovers do not have that much rebound travel or a helper/'tender' spring.

If you're maxed out in adjustment to raise the ride height with the lower collar, you can raise the spring perch even higher (adding preload) to raise the ride height of the car. This does 'pre-loads' the spring, so if you have a 10Kg spring (560lb-in) and raise the spring perch 1/4", you'll actually raise the car ~3/8" (due to the car's motion ratio) and add ~140lbs to the initial seat pressure of the spring.

To simplify: raising the front 1/4" at the spring perch will raise the car more than 1/4", make the initial ride slightly stiffer, and reduce droop travel which may hurt ride quality over big bumps. But if you're bottoming out, it may improve the compression side of the stroke.

I think the main issue you have is that you're running 18/19" wheels (which hurts ride quality) with a lower quality shock, with very little shock travel (which REALLY hurts ride quality). All of these compounding on top of eachother is not a good thing.

KW's and many other coilover brands have a proper amount of droop travel, they run helper/tender springs, and do not suffer from bottoming out in compression or droop travel. Keep in mind that OEM suspensions have a TON of droop travel -which is important for ride quality, especially with softer springs.

Be aware that lowering springs with not enough increase in spring rate could lead to bottoming out the shock in to the bump stop (which is REALLY bad for ride quality). I've driven far more cars with lowering springs that rode worse because they bottomed out in the bump rubber than ones that were engineered properly with enough spring rate to keep them out of the bump rubber.

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[MENTION=16531]stuntman[/MENTION], yes that is the video. I think your post has some excellent info for people here including myself. This is my first adjustable coil over set. My previous Hondas I would just buy a tokico shock/spring combo and be done... The coil overs are a whole other animal for me. I have spoke to BC on numerous occasions but never get anywhere. They just think I need a longer threaded shock. Which are only 100 dollars a peice, but I doubt it will resolve everything. In hindsight, the BC coil overs can be set to ride ok. What they do piss poorly is rebound. It's like stretching a rubber band then letting go abruptly. Also, they are extremely squeaky and create tons of noise prior to warm up in my opinion. Unfortunately my 18/19 wheel set up is staying put. I love it too much... I honestly believe I can have a nice wheel set up without all these issues. I once had it prior to Oem shocks blowing out. Sure it will not be as fast as a 17/8 set up I agree. I might try to add more preload as you suggested just to try it out. Much thanks for the information! I was so close to buying KW, but after dealing with adjustable coil overs, it is kind of something I do not wish to do.
Also, I am not sure what you mean by droop travel, could you please explain?
Thanks!
 
I am at the highest ride height available on the BC up front which is already way lower than the Oem set up even at highest height. These things are built for extreme lowering.It took me about a year to figure out how not to bottom out/have my tire hit the fender. Even at full stiffness if I hit a dip in the road at high speed, you could hear the tire whack the fender. Same thing on my new wider tire set up but I have it pretty much dialed in so that tire/fender rubbing is minimal and only at extreme driving. I have some smashed up fenders from using BC coils.
The difference now is, running full stiffness on my Nitto tires was dreadful but running full stiffness on the Michelin is completely different and comfortable.
I remember when I bolted on th BC coil overs the shock was so much shorter than Oem that I had to adjust the tie rods just to get the car to drive. The drivers side wheel went left and the passenger side went right. Soon after that, the front sway bar shifted and made contact with other parts and some rear ball joints got knocked loose. Luckily the nuts on the ball joints are held on by pins! Also the Oem sway bar carved channels into my type r lower chassis bar.
Just some of the many many reasons I am going back to Oem.


You can buy the SOS NSX-R Chassis Bar Spacer Kit to help clear the rubbing. This might help.
 
Yes I am aware. Theoretically speaking it should not be needed though if staying oem front sway bar. Mine sure did need it though.
I took it off.
 
Droop is the extension of the shock. Jack up your BC equipped car and the wheels don't drop down much. Jack up a stock nsx (or any car) and the wheels will drop down a foot! -more droop travel. Good for keeping the tires on the ground for grip and ride quality. BCs have some of the least travel of any suspension out there. Bummer to hear one brand ruin the idea of coilovers for you.
 
Okay, another update:
I have the Oem shocks in my shopping cart and ready to buy. God damn they are expensive. Which makes KW variant 3 very close in terms of cost. I have also been reading up on the KW and most of the noises generated from them are usually from the control arm bushings. Which made me stop and reconsider. I will not have any height adjustability with the oem's. I think I might just try the KW. I had talked with shad about this a year ago and he said don't waste your money, buy the KW. So I think I will give it a go! If I do not like them, they will be snatched up on prime very quickly.
So who has the best price? I heard [MENTION=4034]Coz[/MENTION] can get them. Also, what are some recommended adjustment settings?
Also, do you need to reuse the Oem spring bushing? Or just the top hat and bushing.
 
Just the top hat and bushing.

Mountain - aggressive setting

TOP ADJUSTMENTS
F Rebound: 3 clicks from full stiff
R Rebound 5 clicks from full stiff

BOTTOM ADJUSTMENTS
F Compression: 2-clicks/sweeps from full stiff
R Compression: 4-clicks/sweeps from full stiff

Street – cruising

TOP ADJUSTMENTS
F Rebound: 9 clicks from full stiff
R Rebound 7 clicks from full stiff

BOTTOM ADJUSTMENT
F Compression: 2-clicks/sweeps from full stiff
R Compression: 4-clicks/sweeps from full stiff
 
^Excellent.
 
Just the top hat and bushing.

Mountain - aggressive setting

TOP ADJUSTMENTS
F Rebound: 3 clicks from full stiff
R Rebound 5 clicks from full stiff

BOTTOM ADJUSTMENTS
F Compression: 2-clicks/sweeps from full stiff
R Compression: 4-clicks/sweeps from full stiff

Street – cruising

TOP ADJUSTMENTS
F Rebound: 9 clicks from full stiff
R Rebound 7 clicks from full stiff

BOTTOM ADJUSTMENT
F Compression: 2-clicks/sweeps from full stiff
R Compression: 4-clicks/sweeps from full stiff

What spring rates do you recommend and what type of springs?
 
They come with 357 lb springs front and rear.
Any changes from there really depend on the rest of your suspension set up, sway bars, and how you intend to drive the car.
I currently run 857 fronts and 527 lb rears and track my car a bunch.

What spring rates do you recommend and what type of springs?
 
Okay, another update:
I have the Oem shocks in my shopping cart and ready to buy. God damn they are expensive. Which makes KW variant 3 very close in terms of cost. I have also been reading up on the KW and most of the noises generated from them are usually from the control arm bushings. Which made me stop and reconsider. I will not have any height adjustability with the oem's. I think I might just try the KW. I had talked with shad about this a year ago and he said don't waste your money, buy the KW. So I think I will give it a go! If I do not like them, they will be snatched up on prime very quickly.
So who has the best price? I heard [MENTION=4034]Coz[/MENTION] can get them. Also, what are some recommended adjustment settings?
Also, do you need to reuse the Oem spring bushing? Or just the top hat and bushing.

Coz is the man.

Like I said previously. Don't waste your time or effort on oem items. I know you've had some bad experiences in the past but don't be afraid. Don't be scared, haha.

Kw's are great, along with some others I may add but coz will be able to dial you in no problem, just listen to him.
 
I had a few other questions for you KW guys, maybe Coz or Stuntman could answer. Being that lowering is achieved by compressing the spring on the kW, doesn't that affect the stiffness of the spring? Also, let's say, you lower it until it cannot be lowered anymore, is the shock travel shortened? I just want to make sure that if I keep about 7/8" clearance on my front wheel that I will not hit the fender on high speed dips and manuvering. If I could have that, plus a excellent ride and performance, I think I will be pretty damn happy with them.
 
Just took the "Before Christ" suspension off the car today. Lol. No seriously, anyone reading this thread the BC are a bargain and a decent set up. They just weren't for me. I'm not what you call slender... They were definitely worth 995 dollars. They also have high resale appeal. I cannot count how many emails I got from buyers wanting them. I also measured the distance from the top hat to the spring perch on each shock. They were all 100% in spec. So I do not disagree the BC 4mm preload video is not a good way to measure preload, but it seemed to have worked in my situation.
Even after having them on the car for 2 years and about 5,000 miles they look brand spankin new. Just look at the pics! I will miss the all black coating. I am not fond of purple and chrome. But I do like yellow. On to the K-dub. Will report back once installed, corner balanced, and aligned.... Also thanks to everyone steering me in different directions and suggesting good taco spots!:biggrin:
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Coz is the man.

Like I said previously. Don't waste your time or effort on oem items. I know you've had some bad experiences in the past but don't be afraid. Don't be scared, haha.

Kw's are great, along with some others I may add but coz will be able to dial you in no problem, just listen to him.
I was scurrred and confused. But prime helped to get me through the horrors.:biggrin:
 

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I had a few other questions for you KW guys, maybe Coz or Stuntman could answer. Being that lowering is achieved by compressing the spring on the kW, doesn't that affect the stiffness of the spring? Also, let's say, you lower it until it cannot be lowered anymore, is the shock travel shortened? I just want to make sure that if I keep about 7/8" clearance on my front wheel that I will not hit the fender on high speed dips and manuvering. If I could have that, plus a excellent ride and performance, I think I will be pretty damn happy with them.

The springs should be linear so the rate should stay the same throughout. And yes, if you lower your car you'll run out of shock travel. Which means poor performance and likely a rough ride since you're more likely to be hitting the bump stops.
 
There are an awful lot of NSXs lowered on KWV3 out in the world.

My best proof of the quality of the dampers was taking my 76 year old dad on a 4hr road trip, and hearing him describe my car as very comfortable. I think you'll be happy or at least have good resources to make it how you want.

Anyway on to the technical stuff:
ccEeYFH.jpg
 
The springs should be linear so the rate should stay the same throughout. And yes, if you lower your car you'll run out of shock travel. Which means poor performance and likely a rough ride since you're more likely to be hitting the bump stops.
That is what I thought. Which I am glad to hear. I do not agree that shock lowering should be performed by simply shortening the shock body. That method allows full travel of the spring with a shortened ride height and is dangerous to say the least.

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There are an awful lot of NSXs lowered on KWV3 out in the world.

My best proof of the quality of the dampers was taking my 76 year old dad on a 4hr road trip, and hearing him describe my car as very comfortable. I think you'll be happy or at least have good resources to make it how you want.

Anyway on to the technical stuff:
ccEeYFH.jpg
Dude come on! I just made tacos last night!!! LOL!!
But I didn't smother them in nacho cheese. Damn you!
Hang on... Is that a pepperoni pizza being wrapped around a taco?? Where is this taco town???
 
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A car is suspended by the spring. You lower the car by lowering the spring perch height. You don't lower it by compressing the spring. KWs have helper springs and more rebound/droop travel so they still have a good amount of travel to not adversely affect ride quality at higher ride heights. Yes as you lower the car you lose compression/bump travel, but a properly designed damper will ha e the bump rubbers set so you have a decent amount of travel. Also raising the spring rate reduces the amount the suspension travels.

On another note, there's more thread on your BC's spring perch to raise the car more by preloading the spring more.
 
A car is suspended by the spring. You lower the car by lowering the spring perch height. You don't lower it by compressing the spring. KWs have helper springs and more rebound/droop travel so they still have a good amount of travel to not adversely affect ride quality at higher ride heights. Yes as you lower the car you lose compression/bump travel, but a properly designed damper will ha e the bump rubbers set so you have a decent amount of travel. Also raising the spring rate reduces the amount the suspension travels.

On another note, there's more thread on your BC's spring perch to raise the car more by preloading the spring more.
Cool, thanks for the info. I just picked up a set of KW from Coz. I'm excited to try em out. The BC went to e new owner at a great price.
 
Glad you got the kw. You'll love them and also supporting coz. He's a great guy!
Thanks. Coz made purchasing them easier with recommended set ups and leaps away from what some would call a fair price. I couldn't say no to that. I think he felt bad for me using anything else. :smile: A very cool guy indeed.
 
Got my KW today. Jeez [MENTION=4034]Coz[/MENTION] has the hook up. They just shipped out yesterday and they are already sitting on my bench!
Will get these babies slapped in this weekend. Coz, your a great member of the community! Mucho thanks.
 
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