Suspension Rebound/Bound Setup & Height Setup - Honda Prelude Forum

KraserK · 05-13-2010, 08:06 PM

I need some information slash ideas on how I should set my car up. For Racing/DD/ Mix of both.

Because alot of things can be diffrent like the spring stiffness height rebound/bound setup etc etc the list goes on. Does anyone know what a great setup would be?

I have BC coilovers the BR type on my car from the 4th gen.

Spring rate is 10/5 (10kg front and 5kg rear) Our cars weigh a **** load in the front so it was quite obvious to go with that setup.

At the moment my height in the front from the centre wheel hub to the guard I think is 330mm and in the back 335mm.

So 330/335mm (Not too low or too high it is kind of perfect I don't want rubbing)

My suspension stiffness or rebound/bound settings are

15/20 from 0 being stiffer and 32 being softer. The front is stiffer than the back.

So what I am asking is

What is your preffered setup for performance/racing?

What is your preffered setup for daily driving?

What is your preffered setup for dd and racing?

And one more question to make my suspension last longer is it better to leave the rebound/bound settings on a hard setting like 10 or on a softer setting like 20?

Cheers everybody!

Kronn 98SH · 05-13-2010, 08:22 PM

From everything I've read, you want the shocks to be stiffer in the rear.

KraserK · 05-13-2010, 08:28 PM

Quote:

Originally Posted by Kronn 98SH

From everything I've read, you want the shocks to be stiffer in the rear.

Hmmm at the moment I have the settings at 15 front and 20 rear so it is softer in the rear. Any reason why it should be stiffer in the rear instead of softer? Reason why I have it less stiff than the front is because the suspension has more travel.

I just realised I missed this

For my

X/Y X = front Y = rear

DD Settings 15/20 - Same height
Performance 8/10 - Same height
Both 15/15 - Same height

Kronn 98SH · 05-13-2010, 08:33 PM

I believe the reason has something to do with the rear being lighter. 62/38

I'd ask this question over on Honda-Tech. They have some real suspension experts over there.

KraserK · 05-13-2010, 08:41 PM

Quote:

Originally Posted by Kronn 98SH

I believe the reason has something to do with the rear being lighter. 62/38

I'd ask this question over on Honda-Tech. They have some real suspension experts over there.

Thanks Kronn definitely correct

spin_r_g · 05-13-2010, 10:47 PM

Majority of prelude track/autoxers prefer to equal spring rates f/r or even higher rear spring rates and a stiffer rear shock setting to help with the preludes understeer. My setup is pretty mild I run 450lb fronts 375lb rears. I have koni's with the rear at almost max and my fronts 3/4. I also have a rear sway bar. But the difference is very noticeable.

I don't have settings for each situtation. Once I hit the track I set it and once I found what worked for me I left it there and I drive on it daily. It's a little uncomfortable at first but you'll get used to it. Unless you have something like Tein edfc where you can change it on the fly I don't think it's worth adjusting it all time.

Artifex · 05-13-2010, 11:47 PM

Quote:

Originally Posted by Kronn 98SH

I believe the reason has something to do with the rear being lighter. 62/38

I'd ask this question over on Honda-Tech. They have some real suspension experts over there.

Or I could just give him the right answer.

Here's the deal:

Once you have a spring rate, that part is obviously not adjustable. 10k/5k is not a good choice IMHO, because the front is way too stiff compared to the rear. It really should be about 60/40 for neutrality. If you want to get something else to fine-tune the suspension, my belief is that adjustable sway bars are much better to use for tuning understeer/oversteer. Springs/struts should be chosen according to intended usage of the car.

I don't know what the wheel rate is for the Prelude (I knew a long time ago, but I forgot). My suspicion is that 10k is way high for a street car. I think most track cars don't go that high. Honda people tend to way overspring their cars anyways, which is a shame.

The problem is that there is an optimal spring rate. Too soft and the car rolls too much, and is hard to control. Too hard, and the car won't maintain traction over bumps. The right rate should be selected according to usage. DD usage should not choose more than ~2x over the stock rate (for most cars).

When people talk about adjusting their coilover, you are talking about adjusting compression/rebound on the damper. For dampers, there is one right setting, and one right setting only. There should be no "adjustment" depending on what you do. I'm completely serious about this. For some reason, people have got it into their heads that the damping needs to be adjusted for this or that. Not true. Damping is designed to compensate for the natural frequency of the car, which is a strong function of your spring rate. Quality dampers you should buy as matched to whatever spring you choose.

BC Racing are OK dampers. I'm a total elitist about dampers, so the stuff I think is good is out of almost everyone's budget, unless they are an elitist bastard like me. IMO, no damper under $2k is any good, except for Koni. Koni is ok, but they have uniformity issues unless they are all hand-matched by someone who knows what they are doing. This is to be expected for a sub-$2k damper though. BC Racing damping is not very good on the plots that I have seen, and they tend to be way overdamped (as well as oversprung). To their credit, they do supply a damper dyno, which is good.

Anyways, back to the point. You should drive the car out on the road, and pay very very close attention to what your suspension is doing. If the car oscillates too much, the damping is too low and must be increased. If the car feels stiff and takes a long time to get back to equilibrium, it's too high and needs to be turned down. You should continue this fine tuning over rough roads until you are satisfied. Once this is done, you never need to touch it again. When I bought my ASTs, it took a month of critical driving to get the damping levels where I wanted them.

KraserK · 05-14-2010, 05:03 AM

Quote:

Originally Posted by Artifex

Or I could just give him the right answer.

Here's the deal:

Once you have a spring rate, that part is obviously not adjustable. 10k/5k is not a good choice IMHO, because the front is way too stiff compared to the rear. It really should be about 60/40 for neutrality. If you want to get something else to fine-tune the suspension, my belief is that adjustable sway bars are much better to use for tuning understeer/oversteer. Springs/struts should be chosen according to intended usage of the car.

I don't know what the wheel rate is for the Prelude (I knew a long time ago, but I forgot). My suspicion is that 10k is way high for a street car. I think most track cars don't go that high. Honda people tend to way overspring their cars anyways, which is a shame.

The problem is that there is an optimal spring rate. Too soft and the car rolls too much, and is hard to control. Too hard, and the car won't maintain traction over bumps. The right rate should be selected according to usage. DD usage should not choose more than ~2x over the stock rate (for most cars).

When people talk about adjusting their coilover, you are talking about adjusting compression/rebound on the damper. For dampers, there is one right setting, and one right setting only. There should be no "adjustment" depending on what you do. I'm completely serious about this. For some reason, people have got it into their heads that the damping needs to be adjusted for this or that. Not true. Damping is designed to compensate for the natural frequency of the car, which is a strong function of your spring rate. Quality dampers you should buy as matched to whatever spring you choose.

BC Racing are OK dampers. I'm a total elitist about dampers, so the stuff I think is good is out of almost everyone's budget, unless they are an elitist bastard like me. IMO, no damper under $2k is any good, except for Koni. Koni is ok, but they have uniformity issues unless they are all hand-matched by someone who knows what they are doing. This is to be expected for a sub-$2k damper though. BC Racing damping is not very good on the plots that I have seen, and they tend to be way overdamped (as well as oversprung). To their credit, they do supply a damper dyno, which is good.

Anyways, back to the point. You should drive the car out on the road, and pay very very close attention to what your suspension is doing. If the car oscillates too much, the damping is too low and must be increased. If the car feels stiff and takes a long time to get back to equilibrium, it's too high and needs to be turned down. You should continue this fine tuning over rough roads until you are satisfied. Once this is done, you never need to touch it again. When I bought my ASTs, it took a month of critical driving to get the damping levels where I wanted them.

Thank you Artifex that is some very usefull information. I guess I know what I am after then! This will take a month for me and damn do I love spending time on the car! (I really do) Thank you I really appreciate it!

KraserK · 05-14-2010, 08:29 AM

Quote:

Originally Posted by spin_r_g

Majority of prelude track/autoxers prefer to equal spring rates f/r or even higher rear spring rates and a stiffer rear shock setting to help with the preludes understeer. My setup is pretty mild I run 450lb fronts 375lb rears. I have koni's with the rear at almost max and my fronts 3/4. I also have a rear sway bar. But the difference is very noticeable.

I don't have settings for each situtation. Once I hit the track I set it and once I found what worked for me I left it there and I drive on it daily. It's a little uncomfortable at first but you'll get used to it. Unless you have something like Tein edfc where you can change it on the fly I don't think it's worth adjusting it all time.

Thank you for that too.

I will definitely be getting into this I want the car to be perfect and of course I will not be thrashing my car for performance its just that if worse comes to worse and I really need to rely on my car for turning performance is there. So I have got this idea that because my spring rates are bad.

I will make the rears more harder than the front (Damper settings) and move on from there.