The Better Bilstein Ebay Coilover Thread
#1824
Spec Miata rates are 700/375 and I've run up to 450 in the rear. The low speed rebound was adequate for track and Auto x work, definitely not ideal but good enough to FTD regionally and have a good time on track.
Guys keep in mind that when looking at the stock spring rates you're looking at only half the spring. The bump stops were designed to be engaged pretty much anytime you're cornering. If you stick with anything below 600/350 then you should leave your bump stops full length. Once you get to 600/350 you can trim the bump stops down so it just keep the tire from hitting metal. I find the ride is better setup like this. This is of course my opinion and there's some wiggle room for personal preference.
Guys keep in mind that when looking at the stock spring rates you're looking at only half the spring. The bump stops were designed to be engaged pretty much anytime you're cornering. If you stick with anything below 600/350 then you should leave your bump stops full length. Once you get to 600/350 you can trim the bump stops down so it just keep the tire from hitting metal. I find the ride is better setup like this. This is of course my opinion and there's some wiggle room for personal preference.
#1825
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Rate choices are going to be a consideration of personal preference coupled with tire compound, ride height, and usage. A setup with one inch of travel before hitting the bumpstops will need a stronger spring than one with one and a half inches of travel. A slick will require more spring to keep off the bumpstops in a corner than a 300tw street tire. A street car will need more travel than a car driving on a very smooth track and can therefore use a softer spring and take advantage of the travel to generate a smoother ride. A car set up to drive on Sebring (bumpy as **** in the middle of big sweepers) will want more travel and compliance to maintain contact and keep from unsettling the car. Ditto tracks with curbs, if you like to be on them.
Bump travel can be gained with extended tophats, shorter bumpstops, or with ride height on the Bilsteins, or a combination of the three.
There are so many opinions because there are many physical setup variations, feel preferences, and driving usages represented in our population. Sway bar choice adds an additional variable to the mix.
There is no "right" answer because it is not one size fits all. Build something that starts somewhere in the middle of recommendations for your particular tire and usage then make adjustments if it doesn't feel right to you. Our cars are all balanced differently between NA and NB and every mod done to the car. A turbo and bigass intercooler weigh more up front than naturally aspirated. Stock NA seats are heavy as F. A/C or not? Stock battery or lightweight? Junk in the trunk? Extra frame bracing NA6/8/NB/MSM? Cage vs. rollbar? Fat girlfriend or meth *****? Everything changes the weight and balance.
Deciding to switch spring rates up or down? Sell the old ones here on the forum to the next guy building his DIY setup. Springs are cheap and reselling them is a snap.
Understeer/oversteer balance is a little off? Make sure you aren't running out of travel front or rear. Contacting the bumpstops or binding the springs on either end will ruin the balance in a corner. If not contacting the bumpstops, add or reduce swaybar diameter, use adjustable swaybar ends to tune, or go up or down on spring rate 25 or 50 lbs or whatever you wish to try. A little critical thought plus trial and error adjustments will get you there... wherever there happens to be for you.
Bump travel can be gained with extended tophats, shorter bumpstops, or with ride height on the Bilsteins, or a combination of the three.
There are so many opinions because there are many physical setup variations, feel preferences, and driving usages represented in our population. Sway bar choice adds an additional variable to the mix.
There is no "right" answer because it is not one size fits all. Build something that starts somewhere in the middle of recommendations for your particular tire and usage then make adjustments if it doesn't feel right to you. Our cars are all balanced differently between NA and NB and every mod done to the car. A turbo and bigass intercooler weigh more up front than naturally aspirated. Stock NA seats are heavy as F. A/C or not? Stock battery or lightweight? Junk in the trunk? Extra frame bracing NA6/8/NB/MSM? Cage vs. rollbar? Fat girlfriend or meth *****? Everything changes the weight and balance.
Deciding to switch spring rates up or down? Sell the old ones here on the forum to the next guy building his DIY setup. Springs are cheap and reselling them is a snap.
Understeer/oversteer balance is a little off? Make sure you aren't running out of travel front or rear. Contacting the bumpstops or binding the springs on either end will ruin the balance in a corner. If not contacting the bumpstops, add or reduce swaybar diameter, use adjustable swaybar ends to tune, or go up or down on spring rate 25 or 50 lbs or whatever you wish to try. A little critical thought plus trial and error adjustments will get you there... wherever there happens to be for you.
#1826
Piggy backing off of what sixshooter said,I think a fair other variable to add into the mix is what bushing / material you are using. A bilstein setup with for example 550/350 rates on stock bushings will feel different than the same shock and spring combo on poly bushings with the sadfab bearings. or on delrin. The bushings act almost as a second spring to the mix like the bumpstops did.
#1827
Thanks for all the opinions guys, I actually ended up deciding to start with the 450/300 setup and going to go from there. I think it should feel pretty good for my uses, and it will probably not see autox/track more than once or twice a year if I'm lucky. I am swapping out for all poly control arm bushings at the same time, so the car should feel a hell of a lot tighter than 150k mile stock suspension and bushings.
#1828
Thanks for all the opinions guys, I actually ended up deciding to start with the 450/300 setup and going to go from there. I think it should feel pretty good for my uses, and it will probably not see autox/track more than once or twice a year if I'm lucky. I am swapping out for all poly control arm bushings at the same time, so the car should feel a hell of a lot tighter than 150k mile stock suspension and bushings.
#1829
#1830
So I have a 1999 Miata currently running stock power, I have installed garage star frame rails and fm sway bars and swapped in the msm bilsteins. I would like to convert it to coilovers like the ones in this thread and would like to know if this sounds correct for what I'm going for. I'd like to lower the car so there's not much wheel gap. The car is a daily but I do go to HPDE events every once in a while. Here is my current part list.
MSM Bilsteins
5x racing coilover sleeves and perches
QA1 7" 550 front
QA1 7" 350 rear
ridetech spring washers
Energy Suspension Coil Spring Isolators
Integra speedthane bump stops
Not sure about what extended top hats to go with, I know I need longer for MSM but how long? Could I do Maruha? Should I go with ISC?
MSM Bilsteins
5x racing coilover sleeves and perches
QA1 7" 550 front
QA1 7" 350 rear
ridetech spring washers
Energy Suspension Coil Spring Isolators
Integra speedthane bump stops
Not sure about what extended top hats to go with, I know I need longer for MSM but how long? Could I do Maruha? Should I go with ISC?
#1833
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If you stick with anything below 600/350 then you should leave your bump stops full length. Once you get to 600/350 you can trim the bump stops down so it just keep the tire from hitting metal. I find the ride is better setup like this. This is of course my opinion and there's some wiggle room for personal preference.
I was planning on just mocking up the shocks without springs with the car on jackstands, jacking up the wheels to see what contacts, and trim the bumpstops to engage (and stop wheel travel) before that. Is there a better approach to this?
#1834
We will put the car on a 4 post to see how much stroke is available before stops engage. On a performance setup, you want the car to be off the stops in straight line driving or gentle turns. Only just touching when near the limits of traction in turns. Most OEM setups have stops engaging almost immediately but those are tall, very progressive stops. For a performance setup on pavement, you will usually want a much shorter and stiffer stop that engages very late.
__________________
#1835
By this do you mean the bronze bearing conversion kit for poly bushings? This is the first I’ve heard of it to be honest, but I’m open to it. I don’t want to derail this thread as it does not 100% related, but is it really that big of a difference? And will it work with any brand poly bushings? I have a brand new prothane kit sitting in the boxes.
#1836
400/325 - damping configuration
I have question regarding to car behavior especially rear axle.
I am trying to find the best valving setup on 400/325 spring rates.
Springs are chosen according to natural freq. but to be honest I am not anymore convinced that it is balanced properly.
Shocks has been already revalved - fronts are for me clear 400 lbs provides with my current valving plenty of grip and amazing level of control, it is still comfortable and impacts are damped well.
Regarding to rears i have blue setup – which controls rear fairly, let ‘s say good.
Car is not flat enaught due to the rear. Probably it needs much more rebound damping but on the other hand I am sure that rear would be completely blocked with more rebound.
My question is if someone uses the same spring configuration ? 400/325 and share opinion. I know that it is subjective evaluation and someone can fell different.
– In my opinion 325 on the rear is too much ( high frequency which comes from 325 spring is annoying even if shock is optimized well )
I am still more convinced that 375/275 would be perfect, and above 300 or 325 on rear it does not work.
I am trying to find the best valving setup on 400/325 spring rates.
Springs are chosen according to natural freq. but to be honest I am not anymore convinced that it is balanced properly.
Shocks has been already revalved - fronts are for me clear 400 lbs provides with my current valving plenty of grip and amazing level of control, it is still comfortable and impacts are damped well.
Regarding to rears i have blue setup – which controls rear fairly, let ‘s say good.
Car is not flat enaught due to the rear. Probably it needs much more rebound damping but on the other hand I am sure that rear would be completely blocked with more rebound.
My question is if someone uses the same spring configuration ? 400/325 and share opinion. I know that it is subjective evaluation and someone can fell different.
– In my opinion 325 on the rear is too much ( high frequency which comes from 325 spring is annoying even if shock is optimized well )
I am still more convinced that 375/275 would be perfect, and above 300 or 325 on rear it does not work.
#1837
You got it backwards, you have way too little front spring......in my opinion. Your front to rear split is way too close, this will be fairly loose but a lot of that will depend on what bump stops your using since these rates are so light you're relying on them while cornering. You sorta alluded to "flat" ride, that horse **** Shaikh was peddling has produced a bunch of ill handling cars. Tune your spring rates for balance.
In my opinion the low speed damping of these shocks are good to much higher rates. The high speed isn't the best, that's where a revalve can really help refine these shocks into a non adjustable competitor to some pretty expensive shocks.
In my opinion the low speed damping of these shocks are good to much higher rates. The high speed isn't the best, that's where a revalve can really help refine these shocks into a non adjustable competitor to some pretty expensive shocks.
#1838
I suppose You are right it terms of split between front to rear. 400/325 it is to close I felt it.
On the other hand I do not feel that car requires to put 500 or 550 for front. Damping forces are matched properly, I am 90 % sure that abruptness on the rear comes from to high freq.
It terms of looseness – car is not to loose. I know that many guys on forum claims that those spring rates are loose, but I do not agree with this. Perhabs if You have slick tires with plenty of grip and car is prepared according to track spec . it can be loose.
I have opportunity to revalve shocks in all range that’s why for me spring is not as crucial thing to swap and swap, with softer rates I can still find agility and amazing control etc.
Bump stops are fixed as well.
I will wait for some comments, perhabs someone who has 325 on back with similar fronts has the same thoughts
On the other hand I do not feel that car requires to put 500 or 550 for front. Damping forces are matched properly, I am 90 % sure that abruptness on the rear comes from to high freq.
It terms of looseness – car is not to loose. I know that many guys on forum claims that those spring rates are loose, but I do not agree with this. Perhabs if You have slick tires with plenty of grip and car is prepared according to track spec . it can be loose.
I have opportunity to revalve shocks in all range that’s why for me spring is not as crucial thing to swap and swap, with softer rates I can still find agility and amazing control etc.
Bump stops are fixed as well.
I will wait for some comments, perhabs someone who has 325 on back with similar fronts has the same thoughts
#1839
I suppose You are right it terms of split between front to rear. 400/325 it is to close I felt it.
On the other hand I do not feel that car requires to put 500 or 550 for front. Damping forces are matched properly, I am 90 % sure that abruptness on the rear comes from to high freq.
It terms of looseness – car is not to loose. I know that many guys on forum claims that those spring rates are loose, but I do not agree with this. Perhabs if You have slick tires with plenty of grip and car is prepared according to track spec . it can be loose.
I have opportunity to revalve shocks in all range that’s why for me spring is not as crucial thing to swap and swap, with softer rates I can still find agility and amazing control etc.
Bump stops are fixed as well.
I will wait for some comments, perhabs someone who has 325 on back with similar fronts has the same thoughts
On the other hand I do not feel that car requires to put 500 or 550 for front. Damping forces are matched properly, I am 90 % sure that abruptness on the rear comes from to high freq.
It terms of looseness – car is not to loose. I know that many guys on forum claims that those spring rates are loose, but I do not agree with this. Perhabs if You have slick tires with plenty of grip and car is prepared according to track spec . it can be loose.
I have opportunity to revalve shocks in all range that’s why for me spring is not as crucial thing to swap and swap, with softer rates I can still find agility and amazing control etc.
Bump stops are fixed as well.
I will wait for some comments, perhabs someone who has 325 on back with similar fronts has the same thoughts
Last edited by tyhackman15; 03-19-2019 at 08:14 AM.
#1840
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Dif Tech pillowball mounts are on clearance and FR Sport.
1.5in: https://frsport.com/dif-10698-top-ha...-front-or-rear
2.0in: https://frsport.com/dif-10697-top-ha...-front-or-rear
1.5in: https://frsport.com/dif-10698-top-ha...-front-or-rear
2.0in: https://frsport.com/dif-10697-top-ha...-front-or-rear