jj1000

Ok, let me see if I can pull these thoughts from my head and make a coherent paragraph.

I'm sitting here thinking about what to do with my suspension. I've pretty much decided on the Tein street advance that 949 sells, (these), but what I'm thinking now is about spring rates. I know the track guys run very high spring rates and that's where my question comes from.

Are race tracks smooth? Is it like cruising around on the most perfect patch of highway you can think of, or are there significant imperfections, ripples, bumps, patches that cause the car to shutter mid corner? I know you don't have to deal with the pot holes that are found all over the city I live in, but I dodge those like landmines anyhow. I figure cars are running high spring rates to control the power and grip, but how does that transfer over to a hard run down a twisty backroad?

I come from the jeep world, so my knowledge is based more on offroad performance, and generally slow speeds. We select a spring rate that is appropriate for the vehicle weight and then select shock valving to control the vehicle/axle movement. There are a lot of vehicles that are over sprung and under valved, where the guys are trying to control the axle with high spring rates instead of proper valving, but I also have a very large range of suspension travel, therefor it's more about keeping tires in contact with the terrain over a large distance.

That's why I ask if tracks are smooth. Are you worrying around keeping the tire planted over imperfections or is more about controlling the torque the tires place on the vehicle/suspension?

I'm going to stop for now and I hope your answers or questions about my thoughts here will lead me to clarity or at least allow me to more clearly explain where I'm going with this.

TL;DR? Should I get high spring rates, turn up the dampening and deal with the occasional kidney shaking hit on road, or shoot for a caddy ride?

concealer404

iTrader: (3)

Is it a street car or a track car?

hornetball

iTrader: (4)

COTA in Austin is SMOOOOOOTTTTTHHHHHH.

Hallett in your neck of the woods not so much.

You're on the right track (pun). Spring rates are there to keep body motions in check. You need to valve to the spring rate. Objective is a consistent contact patch. Size and shape of our optimum contact patch depends upon keeping the tire in contact with and relatively square to track surface. This leads to the desire for low body roll and camber so the outside tire is still square even when roll is present. Etc., etc.

jj1000

Street car, probable won't ever see a track. I might try autocross if my buddy ever comes through and does it with me, but mainly just a backroad toy

Interesting, I've always wondered how tracks differed.

So lets say I'm building my car for twisty roads, plenty of those in the hills around here.

Let's say I'm shooting for 240hp, running a torsen rear, on 300 treadwear tires (no Rcomps because daily driver). Would I be better suited to run the standard 7/6kg that 949 sells, or step up to the 8/6kg? They recommend 9/6kg for track use, I don't want to go that stiff. Edit to add: I have a 1.8 in the car, and plan to run a gt2560.

Now assuming I went 8/6kg I'll be in the very firm category for a street car, but will I see a notable improvement in control, or is there such a thing as too much spring?

I don't know how I'll feel about the HP when it comes time to rebuild the motor, but there's always the possibility (probability) that I'll put forged internals in it and want to step the power up, will I still have plenty of suspension to handle it, or will I also end up wanting to re-spring the coilovers?

All this and I haven't even addressed sway bars, from what I've gathered though, sways in a miata are more about balancing the car out once the suspension is sorted. Am I on the right track there?

Just a side note, I'm not afraid of spending money on a suspension, but that's not saying I'll put Xida's on the miata seeing how they cost more than the original purchase price. However, my jeeps suspension is nearing the purchase price of my miata, and now where near dialed in how I'd like.

What I do know is that I want to be the front car, not the rear.

thenuge26

iTrader: (2)

For a street car, I'd wait for the 949 Technas that should be coming out soon (read: Q2 2020). If your car will never see a track, who gives a **** how smooth tracks are? Get something that will be good on the bumps you will have to put up with.

For reference, I have 550/350 springs, and its pretty stiff. Stock are like 110/90. For a track car you would want 700/400 or higher.

jj1000

I like the tein's because they're rebuildable. Valves wear out, oil get's old, shocks get blown. I'd like to be able to ship them off and get fresh shocks back without having to buy new.

I ask about tracks becasue everyone seems to want a race car, because that's the pinnacle of performance, but not everyone races. However racing is were R&D happens and that translate over to those of us that like to drive our cars hard. I'm just curious how much racing knowledge I can use on my car without turning it into a shitty street car. I've read about FMs targa miata because as much as that's a race car, it still ran on public roads, but I don't want vmaxxxxxes because they aren't rebuildable. I hate the fox shocks on my jeep because they aren't rebuilbable and I blew the seals out of one on a square rut. Not that I'll be crossing ruts at 30mph in the miata, but the idea is the same.

Thanks for mentioning the spring rates, that's right were I'm thinking I'd like to be.

As for wondering about a tracks smoothness specifically, I'm really just curious if these guys are running these high spring rates on the paved equivilant of glass, or something that at least resembles a nice backroad.

thenuge26

iTrader: (2)

Racers run higher spring rates because they run wider, stickier tires.

If you want a stiff horrible ride on the street instead of something softer that will not perform as well, I can't stop you. But as far as performance, what is a large difference on a track is probably not noticeable on the street.

jj1000

Ok, that's kind of what I was thinking. They run the suspension to deal with traction, and tracks are smooth enough to allow the stiff suspension.

I never intended to run SM spring rates, just wondering if I'd be happy with 7/6kg, or could use more without knocking a kidney off it's hanger.

Fireindc

iTrader: (13)

You do not want a track suspension on a purely street car. I don't know how YOUR backroads are, but mine are nothing like a track. You get bumps, dips, divits, ripples, potholes (dodge these), patches of sand, etc. You want a suspension that is firm with minimal body roll, but that can still work (read: has enough travel) for public roads.

hornetball

iTrader: (4)

More smooth = less suspension travel needed = higher spring rates.

And vice-versa.

Dampers need to match the springs (including the additional spring rate from a roll bar).

500ish/300ish makes for a decent street suspension assuming properly sized dampers.

I've got FCM with 550/325 on my silver car. Me like!

Red track car is getting 700/400 Xida CS.

I'm not an expert . . . I just buy highly regarded suspension bits from those who are and listen to their recommendations.

jacob300zx

anything from 250/150-450/350 with sway will feel sporty and fun.

I would buy these Bilstein Sports
99 1999 Mazda Miata Shock Absorber - Suspension - Bilstein, KYB, Front, Rear - PartsGeek
$424
450/325 springs with collars
Front Rear Aluminum Scaled coilover 0 3" Spring Kit 90 97 Miata MX 5 MX5 NA Blue | eBay
$60
Foam bump stops
Ground Control - Foam bump stop ($12.00ea)
$48
NB top hats
Flyin' Miata : Chassis : Suspension components : NB shock conversion kit
$209

Should be a nice setup for 750ish

concealer404

iTrader: (3)

Are those the sleeves/collars that everyone is buying these days? Then just loading with decent springs?

Fireindc

iTrader: (13)

Good deal on the bilsteins, and IIRC you can have those rebuilt and revalved down the road and make them pretty uber.

jacob300zx

Maybe, but I don't know why. I ran those springs/collars in 2008-9 on my MSM. Had about 15 track days, 10 autox, rallyx, and about 15k street miles on them when I sold it. Still drove great. First time I met Hustler at MSR-H we were triple driving the car that weekend and he asked what suspension I was on lol, he actually got under the car and looked, thought I was bullshitting him.

jj1000

Do the bilisteins have enough valving to handle those spring rates? For a non adjustable set up I could get 949's technas or tein basics, and not be paying much more than that, without having to **** with multiple shipments or putting anything together.

Just so people don't think I'm crazy, I never wanted to run full on race spring rates, just wondering how they get away with them, and how close I can actually get without having a car that's literally pain in the ***.

carnut169

If the car is 100% street you should not set the car up like a track car. It will be a terrible experience.
I loved the Fm illumina setup.

All tracks are not the same. Sebring is a rough bumpy bitch, barber is as smooth as glass. Others I've driven (Roebling, VIR, CMP, Road Atlanta) all fall in between.

jacob300zx

Yes I would rather have the Bilstein setup above than any sub 1k coilover. I picked you out a nice daily driver/twisty road setup. IMO Bilsteins are better than Illuminas, AGX, and Koni for a nice riding OTS shock.

Google
Site:Miata.net quinesintial eBay coilover thread
Enjoy the reading

Alpod

iTrader: (2)

Ok, I'll chip in here. I have a 93LE with factory 20 year old suspension (bilsteins, etc..) and a friend with a BRG and 4 month old street advances (7/6kg). The teins do obviously feel "newer" and do absorb shocks and abrupt street bumps a little better. However, I've been told by another friend who has driven both mine and his car back to back and agrees with me that the bilsteins do feel "sportier" around turns and aggressive driving.

I'm not saying either is better, and our cars are setup differently, but in my case and with my experiences I would (and will be) just rebuilding my bilsteins over buying new coilovers.

z31maniac

It is, but even the 800/500 XIDAs with RB hollow front/MSM rear deal with it just fine. I was amazed at how compliant it is.

jj1000

That's interesting. I'm sure new blisteins would feel just as new as the teins, and handle the little stuff the same.

I found that thread last night looking for info on the coil sleeves. Thanks for putting together the shopping list. I'm a little slow to change my mind, but I'm thinking that might just be the route I go.

Two questions: How do I know what spring rate I'm ordering, I can't find it on the ebay page, and can I use these factory tophats?