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Is Whitener (spelling) still around? What about the circle track guys who were doing this?
Actually yes he's still around. He was the only one I was able to get an answer from who actually didn't quote an arm and a leg. He doesn't have a 3 month wait list though so if i use his services I'm going to wait for next winter
I've been on my DIY billie setup for 3 years or so now, and I love them. They are great for the street and can handle the track pretty well, though I think at my power and grip levels I'm at the limits of the spring rates I chose (450f/300r). The car has FM sways front and rear. And ISC tophats front and rear. A pic for reference:
The setup was built with budget, performance, and comfort in mind. A cheap suspension that will eat up the 3/4 mi dirt road I live on, but still be able to handle the track.
Alignment specs are the supermiata dual duty specs, 125mm F ride height at the pinch, ~5mm or so of rake. FM sways on soft rear / middle front.
Now I have questions for the professionals. Clearly at ~220whp I should have more spring rate, but the billies simply won't properly handle much more spring rate, so I'm hesitant to try higher rates. Xidas are in the future, hopefully next year, but for this year I want to continue tracking the car as much as possible and optimize what I have.
My first question is, with these springrates, 220whp, and 15x9's / 225 rt660's should I be relying on the bump stops to affect my handling balance. Or, should I cut the bump stops to the shortest possible length so that parts don't contact and rely only on the springs?
Next, should I try to squeeze more spring rate out of this setup? I've thought about going to 550f 350r or similar, and see if the bilsteins can keep it under control enough.
I definitely want to remove some of the forward rake as well, as the rear end is giving me some stability issues, and always oversteers at the limit. I'd like to induce a bit more understeer out of the car, or at least get it more neutral. Here's a vid from one of the last events:
Since that event I actually softened the rear sway bar and it's a bit better, but it's still not perfect. I'm also going to try the race alignment settings instead of the dual duty ones this season when I get an alignment. I don't put enough street miles on the car to care about tire wear in that aspect, the track eats 90% of my tires as-is.
Edit: There's also a concern that my bushings, particularly those in the rear knuckles are shot. I had the car on the lift after the last event and it didn't look too happy. Thus I have Supermiata bushing kit going on the car right now. This post is just looking for a discussion of what other things I should change at the same time.
@Fireindc I think the racing gurus here are going to tell you less rear sway bar. My track/auto-x friends tell me all the time that I should go to a stock NA6/maybe NA8 rear bar for track days and drop a rear endlink completely for auto-x I'm at 500/325 rates on DIY Bilstiens on the tubular Racing Beat front and the small Racing Beat rear bar with around the same power you have (15ish psi on a custom TD04 soon to be an EFR6258) and the car is super playful (read slow) and easy to induce oversteer but not terminally to the point where it is scary. Take all my stuff with a grain of salt though because I suck and really am just going by what my much faster than me friends have said.
Here’s a caffeine fueled brain dump from toilet. Could belong there. ymmv.
Been running 750/450 for quite a while on my 6758 turbo car. Put the 450s on the back of our ChampCar for 800/450 on Penskes and went with 750/400 on my car with DIY stock valved NB Bilsteins in an attempt to control rear a bit better. This may be due to valving. Custom NB 1”f / 1.5r” rear ext top hats. See posts in here for using conduit to extend and weld. Use NB hardware and turn down large washer to fit in conduit. Keep conduit long in NB cup to center spring. No isolators, I don’t need them.
My car is used mostly for AX and some track days. Occasional street and even .75mi dirt road. Biggest RB front bar. Stock 95 rear bar disconnected. 15x9 w/ 245 Falken 660 or 225 Re71 grip levels.
I came from unknown lowering springs on Tokico blue shocks. I would describe the ride as awful before. Soft and always bottoming out on NA stops.
Going from that to 750/450 and 205 Re71s was night and day difference in handling and ride quality. It did not seem too stiff from what I was coming from.
Emilio has stated .60 to .65 ratio for F/R spring rate difference and I don’t see it followed much in here. Lots of 450/325 range and I wonder if ride quality would actually feel better with more front spring on those cars.
Thanks for the input. I spent some time looking at popular race setups and found that my car currently with FM front/rear bars has a FRC of 53%. I picked my spring rates based off the golden .60 to .65 ratio but didn't consider how much the sway bar setup was throwing that off. I guess that's what I get for throwing parts at my car without fully understanding what I was doing.
The top row is my current setup with FM front/rears and my 450/300 springs.
The middle row is with the stock 12mm rear sway bar. Much better, I should have ran the car like this (but never did).
The bottom row is a spring setup I'm considering trying and it mimics the FRC of some popular racing setups. It uses my FM front bar with a stock rear. I could also keep my 300r rate and bump the fronts to 550 to achieve a similar FRC without over springing the dampers as badly.
I feel like the car could really use some more spring rate, it makes a bit too much power (and squats) with 300 lb/in springs in the rear. These might be pushing it on stock valving but I might give them a shot for the season.
Input as always, appreciated. I'm in the middle of building a garage so I've gotta make the most out of this setup for now. Thanks!
Thanks for the feedback. I settled on 550 rate springs in the front, gonna keep the 300's in the rear. Ditching the FM sway bar for a supermiata unit (on order), which should put me right at a 61.5% FRC on the softer setting.
I'll update here once I get the car together. It's going back together with the supermiata 836 poly bushing kit. The car will still be a bit undersprung, but I plan on switching to xida's next year if I can swing it.
I suspect that one of my FCM shocks is bad (40K miles). I have a quote to rebuild just a single shock at around $350.
Since I have all the bits to fit NA HD Bilstein shocks, I am considering purchasing (4) of them and just replacing the (4) shocks.
That would be 24-014885 and 24-014892.
NB1 @ 2500# ELBJ's
Front 425 #/in
Rear 275 #/in
Front pinch weld 5.500 (EDIT 23Jul22: Was a typo at 5.25)
Rear pinch weld 5.625
Front roll bar is Eibach 27mm solid (slightly less #/in than Racing beat 1.25" hollow)
Rear roll bar is Stock NB1
NB1 top hats all around (with the NA shocks, that gives me all the travel the suspension can stand without hitting arms on things)
I'm not unhappy with the set-up, except that the RR tends to hit bump stop on dips, which is why I suspect issues with it. I have not yet further evaluated the shock.
I am also willing to raise the car a bit.
Comments please.
Last edited by DNMakinson; 07-23-2022 at 05:29 PM.
I suspect that one of my FCM shocks is bad (40K miles). I have a quote to rebuild just a single shock at around $350.
Since I have all the bits to fit NA HD Bilstein shocks, I am considering purchasing (4) of them and just replacing the (4) shocks.
That would be 24-014885 and 24-014892.
NB1 @ 2500# ELBJ's
Front 425 #/in
Rear 275 #/in
Front pinch weld 5.25
Rear pinch weld 5.625
Front roll bar is Eibach 27mm solid (slightly less #/in than Racing beat 1.25" hollow)
Rear roll bar is Stock NB1
NB1 top hats all around (with the NA shocks, that gives me all the travel the suspension can stand without hitting arms on things)
I'm not unhappy with the set-up, except that the RR tends to hit bump stop on dips, which is why I suspect issues with it. I have not yet further evaluated the shock.
EDIT: If so, do you know the body lengths of the NB B6?
EDIT 2: Found such lengths from earlier posts.
EDIT 3: I finally realize that you answered my question directly... Thanks. That is the approach I will take.
Last edited by DNMakinson; 07-20-2022 at 04:58 PM.
EDIT: If so, do you know the body lengths of the NB B6?
EDIT 2: Found such lengths from earlier posts.
If you want to run 5"+ ride hight the stock NB HDs will work. My car with 500F 325R rates was perfect at that hight with properly sized bump stops and NB top hats. With 300+ TW tires those rates even worked enough at Auto-X and HPDEs. I have the hollow RB front bar and the smaller adjustable RB rear sway bar and I can't think of one time I ever bottomed out on a stop. I wasn't happy with this ride hight and am working on completely changing my setup with extended hats among other things but If you are happy with the hight the car is there is really no need to go to the shorter bodies.
With the shorter body NA B6s you will have to buy new bump stops and cut them down to prevent tire/suspension arm to body contact. If you want to stay at a higher ride hight all you will be doing with the NA Bilstiens is losing droop travel. If you want to go lower you can get the NA B6s OR extended top hats with the longer body NB set. With rates as low as you are running either set will work but I still think the NB set is better valved for them.
Well , been studying this thread for a while now , and the usual conclusion I got was “if I were to do it again , I would just have gone with the Xidas” , fair enough , I want to buy the Xidas,I really do , let’s do the math together.
Xidas 2450$
Shipping 215$
Sub-Total 2665$
Did you know the VAT here in Greece is 24% ? Oh yes
And the total is …. A whopping 3300$… Now I am sure I can’t afford a set of Xidas.
(I am not saying the price of Xidas is not reasonable , I just can’t afford to pay another 850$ just to get them.)
Let’s discuss options.. Consider that I want something brand new and my budget for now is close to 1500$ (shipping and VAT included)
Forget about the Teins , BC, Konis, Meinster etc etc
Feal’s cost me around 2000$ to get.
Xidas and fox are way out of my budget.
I am trying to avoid the DIY billies because of the factory valving , since there is no person here in Greece that actually knows how to revalve … and if I were to send them out every time I wanted to change the valving , I’d be better off buying the feals.
I feel like I have no options.
Has anyone tried the maruha ones ? They are close to my budget and I love the fact that maruha has parts specifically designed for the Miata.
Do I have any other option ?
You forgot the import fees and additional expenses such as custom clearance fees, plus the USD/EUR exchange rates that have gone to hell lately. Exactly what holds me back as well.
I do have a set of Maruhas that I have yet to install (bought used in Japan a while ago). My issue with them is that I want to run soft spring rates, at almost stock ride height, and need a lot of suspension travel. This is why I will probably go with custom-spec ASTs; I may let my Maruha go (located in Greece BTW). Feel free to PM me.
Shockworks was started by chassis engineers that used to work in the automotive manufacturing industry in Australia before it shut down. I believe mainly Ford, Toyota and Prodrive.
Both come very highly recommended within Australia. Shockworks has less information on their website, but don't let that put you off, they tailor their coilovers to your needs rather than offering different off the shelf options.
Not sure what the import duty would be like, but the weak Australian dollar may make it worthwhile.
02-24-2022, 10:16 PM
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