Bunch of suspension questions.
 

How is optimal brake balance determined?

What are spring rates, how are they chosen, how are they measured, and what do they control or produce or benefits they offer if they are stiff or unstiff?

What is rebound?

What does adjusting sway bars do?

How are shocks chosen, and why is one superior then another?

How are shocks paired to springs?

Is it possible to have a better shock/coil combination but maintain stock ride height?

How do those electronically adjusted teins work? What type of control do they offer?

How is optimal brake balance determined? Basically you want the rear of the car to slow down as fast as the front of the car so it doesn't come around but you don't want it to lock up early.

What are spring rates, how are they chosen, how are they measured, and what do they control or produce or benefits they offer if they are stiff or unstiff? The amount of force it takes to compress the spring(or whatever you are talking about) the distance quoted. So 550lb/in springs for Ground Controls take 550 lbs to compress the spring 1 inch. It takes another 550 lbs to compress it another inch. Obviously the higher the spring rate the less body roll you will experience but higher spring rates load a tire quicker which can cause it to break loose sooner. If you are gonna raise your spring rates or stiffin your sway bars you should make sure you get tires that are up to the task. Flatter corning doesn't always mean better handling. A car with stock suspension running crappy all seasons at the edge of their grip level will be easier to keep from breaking loose than a car with much higher spring rates. Compliance is a good thing when it comes to grip, especially in low traction conditions.

What is rebound? Opposite of compression when talking about a shock/spring

What does adjusting sway bars do? Adjusting endlings allows you to take preload off or put it on the sway to change the handling. Can help get rid of oversteer or understeer. Adjustable sway bars have softer and harder settings. 1 reason is for body roll control. Another is to balance a car's front to rear handling bias to change it's oversteer/understeer characteristics.

How are shocks chosen, and why is one superior then another? Some chose shocks because they have adjustable perches, some choose them for adjustable valving, some choose them because they have better or stronger valving.

How are shocks paired to springs? Shocks should be matched to springs based on their ability to dampen that springs rate. If a shock is too weak it will not be able to control the bouncing motion of the spring, much like a blown shock. If it's too strong you will over work the shocks instead of letting the springs do the work.

Is it possible to have a better shock/coil combination but maintain stock ride height? Yes.

How do those electronically adjusted teins work? What type of control do they offer? who cares, they probably cost a fortune.

Try reading on:
http://www.corner-carvers.com/
Lots of great info there.

Tein's product page:
http://www.tein.com/products/edfc.html

And a nice article on them:
http://tinyurl.com/6e4f3q

They are little motors atop each perch. Damping control from right inside the car.

Vash-

Those were banned from Formula One over 15 years ago. Sad it's taken this long to see them on road cars.

What is damping control do exactly, give me an example of where I want a lot of damping and very little.
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Thanks for the answers Paul.

What about this. Say I change my shocks and keep my coils or vice versa(obviously to better ones), what happens if I only change one.

What do adjustable perches do?

I don't know a ton about suspension, but from what I understand;

Damping controls how fast the shock reacts to load. I guess on one side of the spectrum there is damping settings for comfort, then there are settings for control.

I'm sure someone that knows the suspension in and outs will explain better. :)

EDIT: Just found this on Google. I was curious myself to learn a little more. This site seems to sum up suspension in a whole pretty well. Page two explains damping front to back.

http://www.carbibles.com/suspension_bible.html

Vash-

my friends 1990 300zxtt had it! it's 18 yrs. old! also, tein has had the edfc available for years now.

My 87 Thunderbird has it.

very rarely will you need to change your damping on the fly. trust me, this is coming from a guy WITH the EDFC and I find it unnecessary.

if you were a rally driver you might want to.

basically you can change the firmness of shocks to suit road conditions. rougher roads may require a softer shock to better absorb the road bumps and provide better traction. smoother roads may be better suited to firmer shocks.

really the bottom line of the adjustment is: which is faster? if you have them soft for one lap and hard for one lap, the better setting is the one with the lower lap time.

my 89 mazda 626 turbo had it :) boo yah.

How noticeable is the difference in ride? Say for example I want them soft in the city, and stiffer on the highway.

Would that be worth getting these Teins for this feature alone?

Hypothetically speaking.

it's real damn noticable. i run them full soft ALL THE TIME. full hard is ridiculous. so like, smooth road race sure.

Hmm. Something to consider for the future.

Dont IM me Chad, I know what youre gonna say

I love these threads. Thank you Sam! :bigtu:

They give me the chance to learn without having to ask stupid questions! :giggle:

Keep the links coming guys.

Thanks

There is no such thing as a stupid question.

Were you around when I asked all my turbo questions. I thought Braineack was gonna ban me for all the threads I Hijacked.

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Heres a stupid question.

What if I wanted to put airbags on my car? Would that offer better or worse handling then a similarly priced(if possible) spring/shock setup?

How about a few examples of situations and type of spring/shock combinations? Say road racing, daily driving, comfort, all around. Not models of springs and shocks, but what spring rates would be ideal for those conditions.

Coming back to how shocks are paired to springs. Paul said its based on the ability of the shock to dampen the spring rate. Does that means shocks come with an operating range? If so, what if the particular spring rate is in the lower or upper operating range of a shock, what happens?

What does a thicker sway bar produce? Do the benefits of thickness diminish after a certain point(shutup pervs)?

Other than pre load and thickness, what else ties into the effectiveness of a sway bar?

Here's another question (sorry Sam but it's in the same subject): why does everyone in the Miata community always suggest that the rear sway bar must be taken out when the suspension is changed to a shorter spring based one?

I am not sure this applies to all aftermarket setups. But in my case, with the Tein Basics, I removed the rear swaybar to reduce some of the oversteer created by the relatively stiffer rear springs. It seemed to help.

If you go to Fat Cat Motorsports they have a suspension spreadsheet that calculates the tendency for oversteer/understeer for any configuration of F/R sway bars and spring rates.

Thanks; btw, (my apologies again Sam) I have the tein basics also installed with the FCM bumpstops and I can't get the ones in the back from hitting them every time I hit a pothole no matter what I do. :bang:

Any suggestions?

Thanks

Active suspension debuted in '83, was finalized in '87, and banned in '93.

There's also a big difference between fully active suspension and a two-stage electronically switched shock :)

I still have my rear sway in and always remembered thinking I read somewhere that it should come out. Maybe I'll take it out and see what its like....

Vash-

yeah, but if you ARE on a smooth road course, you can adjust them before you get in the car and drive. not to mention you wont even be fiddling with that shit when you're driving on the track. unless you like the color of wall on your bumper.

When it comes to suspension, you can't look at each item separately, you have to look at it as a whole. Your tires are the starting point. With shitty tires you are best off on stock suspension as it is soft and doesn't load the tires like Paul said. If you upgrade you tires to better gripping ones, then you will benefit fomr less roll, which means everything has to be changed. Stiffer springs will help the car roll less but it is ok since the tires can handle it now. Stiffer springs rebound quicker as well, that is why you need "harder shocks". "Harder" shocks are now needed to prevent the tire from hopping up and down after the spring compresses in a situation because it will want to bounce more now since it is stiffer. It is important to have your valvin matched to your springs rate for this reason. The stiffer the spring, the stiffer (harder) the valvingin the shock should be. Having the best set up means it has to be matched to each other. The stiffer your shocks and springs,the more grip you need in order not to overload the tires. Then come stiffer sway bars. A stiffer bar will further help reduce roll, again, not something you need with shitty tires, you are reducing roll to make better use of your tires, but if they are shitty, you are only making matters worse. Assuming you do have grippier tires, you want less roll, with less roll you are maximizing the grip of your tire. Endlinks help you fine tune your desired roll, much like spring rates. If your spring rates are higher, you get less roll, if they are lower, you get more roll. Endlinks allow you that type of control, in a different way though. They allow you to adjust the tension of the sway bar. Softer setting will allow more roll, harder setting less roll.
Sway bars keep the two sides working somewhat together. When you are turning, you put all the weight on the outside of the car, naturally the outside wants to dip but the inside wants to lift since the load is off of it now. Sway bars halp take some of the load of the outside and try to put it on the inside. This helps you in several ways, first it helps you not overload the outside tire/suspension, second it pulls the inside tire/suspension down, this will give you better overallgrip since you have the two sides working together now.

The rear sway does not have to be taken out. In lots of cases it helps if it is not there, but not everyone has to do this. I still ahve my stock rear bar in place.
The reason a lot of people remove it, is to maximize grip coming out of a corner or in a corner in general. The miata does not have a lot of travel in the rear suspension components and when turning if you have stiff springs back there, the inside tire does not have a lot of load on it and does not grip well, we all know what happens then. The point of taking the rear bar out is so the rear is more independent.

Also, Sam, there is no such thing as an ideal set up for more than one type of driving. If you plan to track your car and drive it on the street, you will have to compromise. Decide what is more important to you and build your suspension to suit your wants and needs.

I hope I make sense, it is late andI'm about 6 brewskies in. Good night!

Oooops, sorry for not making this shorter, I got carried away.

Nice I have a question too!

I'm about to make my suspension: FM coilspring with koni. I'm thinking for FC bumpstop too but I'm affraid it won't be enough as the road are very bad around here. I read somewhere about NB tophat? Someone can tell me more about this?

You put the NB top hats on there to increase shock travel, thereby keeping the car off the bumpstops. Basically, the spring's location to the car doesn't change, but the shock mounting point is raised about an inch. This allows for another inch of suspension travel before you contact the bumpstops, if you stay at the same ride height. The main advantage comes from putting them in the rear.

I've got kyb adjustables, so I have to crawl under the car to adjust them, and I hardly see that as a burden when I go from road to track, or vise versa.

I had the same issue with bottoming out in the back, so I made some spring spacers, FCM used to have them, but I can't find them anymore.

I think the main reason people remove the rear bar is because the spring rates that come standard on many coilovers do not have enough difference front to rear and the car becomes more tail happy. Removing the rear bar fixes this, it also gives you more traction. There are downsides to removing the rear bar as well, which you can find reasons for by searching (I'm not positive on the technical reasons) I personally have had that kind of setup and now have changed to a higher front spring rate and retained the factory rear sway bar with a hollow RB up front and much prefer it this way.

I like your approach much better than taking out the rear sway bar. Also, fwiw, ever since I first bought my Miata with stock suspension I always found it "tail happy" when compared to other cars I've owned. The oversteer actually improved when I first installed the FM springs with Bilstein shocks; go figure!

What ride height are you at? With the basics and SS because they don't have an adjustable shock body length like the flex you have to ride a lot higher than they suggest from tein if you want anything close to an acceptable (not bottoming out all the time) ride.

I am at 12.5"F 13"R with NB topmounts and cut tein bumpstops (removed 1 ring) and I finally have enough travel to not bottom out when driving hard on bad roads, but I am thinking about ISC topmounts so I can go just a little bit lower and still have this much travel.

I know that it sucks to hear that you have to go higher, but so far thats the only thing that has been able to fix the shit ride.

And johndoe, where did you get the new front springs from? Tein? Do they cost a lot?

I personally mess with my teins quite a lot, so EDFC would be nice at times, but one of the good things about these shocks is that they take barely any time at all to adjust versus the under the car kind.

I got the springs through Emilio and yes they are Tein springs. The price has gone up since I got mine, they're now $120 a pair

http://949racing.com/index.asp?PageA...PROD&ProdID=50

What would I buy if I wanted shocks for the following?:

90% street driven, something that will make the car feel more sure footed. Wont bounce around and shake like an OX cart when traversing bumps and pot holes. Wont understeer in corners so much or feel like it doesnt want to turn, and wont roll like the titanic.

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How do you guys know, what spring rates you need? What is the indicator that you need 500# for the front and 400# for the back? Why more for the front?

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Im looking at Koni's site. They sell a coilover Kit, sport yellow. No indication of any of the important parameters. How do I know what kind of enhancement they will produce? I know some of you run these, but other then personal experience what do you base the purchase on?

600 bucks seems like a bargain to me. What else is in the same neighborhood?

konis out of the box aren't very nice. something interesting would be tein basic or illuminas and fm springs or something to that effect.

sam, i like the set-up i have kyb agx's with fm springs and FCM 36mm bumpstops......4 in the front 3 in the back....its nice and tight but the bumps aren't reall that bad....next time you come down to the area you can take the car for a drive to see and i'll bring you to some bumpy ass road to get a real feel for em

you mentioned you don't want to understeer into corners. the others will correct me if I'm wrong, but I'm fairly certain that has more to do with sway bars, if you ignore tires, tire pressure, road condition, etc. which all have to do with understeer/oversteer

I have FM's front and rear bars. stock I had a little understeer into corners, and anything more then a little wiggle of oversteer and I would spin. changing nothing but the bars, I experienced (besides the decrease in body roll) significantly less understeer and incredibly easy-to-control oversteer, no matter how sideways I got.

From what I've seen, Illuminas look like they offer alot esp for the price (380 ebay)

However, reading the "list ur setup" thread, doesnt seem like many people are going for them... dunno y tho?

what are your spring rates?

For 90% street driving and nothing serious, just get the factory Bilsteins used from someone for sub $200 and get some FM springs, and get the RB front sway bar and call it a day.

*ninja edit* you need some real rubber as well, no matter how responsive your suspension is, how stiff or soft, if your tires suck balls, so will your handling...get real rubber, I know it's expensive, but it's what makes the biggest difference.

I would rather buy 100K mile used OEM bilsteins than new Illuminas, I just don't like them...

For what Sam seems to want, he'd be best of on the Bilsteins and slightly lower slightly stiffer springs. He could do it for less than $250 i bet, if he bought smart and cheap, he jew, so no worries there. :giggle:

I cant have the car lower, thats my #1 priority. Brooklyn streets are OK, but in the city lower will have me shedding parts because the roads are so bad.

Can I get stiffer springs, but not lose ride height? Why cant I reuse my stock shocks?

I don't have a spring compressor and honestly don't want to fuck with one, I have heard some bad stories. Id rather just buy a set and install it.

Yea, I think my rubber is the biggest problem. I am running on General Exclaim UHP's. When I was buying these it was either these or Hankook RS2's. I skimped on 40 bucks like an idiot and got the cheaper Generals, BIG MISTAKE.

Car felt boaty right from the start. They are very grippy, ride very well, and are great for all types of weather. Drove in the winter with them fine. But they have very soft sidewalls and cornering is disconcerting, the car turns and turns well but it feels like its gonna let go at any moment.

I think I will pick up those RS2's first before anything suspension related.

Why FM springs with Tien Basic? Why not Tien springs?

I'm just curious how you guys determine the appropriate combination.

I want to improve the base handling of the car without spending loads of money on suspension parts. I have the money dont get me wrong, but the trick is spending on what I need not on what I dont need.

How about the FM 2.5 kit? Seems affordable, price isnt bad for what you get and I like the idea of added travel in the back because I hit the stops most often in the back.

Koni sport or race? I like the race a lot--tried them on an NA and a NB.

Dan's GC coilovers are also pretty freakin sweet.

yellows. whatever the plain jane adjustable ones are. hate em. hated em on my e30.

oh and sam, tein basic come with springs.

Find the correct size, then the spring rate should be determined using a mix of the fatcat spreadsheet and alot of testing.

In the most basic way of looking at it, shocks should be chosen or valved based on the spring rate.



Shocks and good rear mounts will give you the biggest day to day improvement.

Oh, thats not a bad price at 900.

Sam-you can get stiffer springs and not lower the car, I think the FM springs lower it just a bit though, nothing major. That's why I recomend the OEM Bilsteins for you, they are stiffer, smooth, last forever, and are pretty cheap used. You can not beat them.

Y8S-I have the Koni Yellows, and E30 might be a different scenario, I absolutely love mine, they feel smoother than my old R package suspension, and perform way better, out of the box, not re-valved. I do plan to eventually re-valve the front only because now I want even stiffer springs up front, I am at 650 now, I want north of 750lbs/in.
My friend just got koni race/gc for his 370whp MKVI Golf and loves them to death, very pleased with them, ride and handling. Another friend has the koni yellows on his 450 whp E36 M3, very happy with them, but he does not push the car much at all, so he may not be the best example.
IMO Koni Yellows with softer springs sub 350 make for a very civil ride.

On auto-x's, with this set up, I am usually the fastest street tire Miata, and usually I am faster than some of the Hoosier A6 Miatas. I am very happy with my suspension, but I do feel the need for some R compound as I feel I am at the limits of street tires right now.

http://cgi.ebay.com/ebaymotors/Bilst...spagenameZWDVW
you may want to look into this

btw-you dont need a spring compressor when changing springs on miata shocks. I have never used one, well, i have, but this was before i learned to do it the rigth/easy way. Just lay the shock on the side, step on it with one foot, use air gun to slowly take the bolt of, and you're done. Then just reassemble.

Keep in mind that when it breaks loose it will throw the air gun up. I've shot shocks halfway across the shop floor before.

It has yet to happen to me, but I can imagine how it could lol

Im confused. You say OEM bilsteins, what does that mean? To me it means, whats already in the car.

So you're saying just change the shocks basically?

He means the R-package OEM shocks.

They're all yellow. The less expensive sports in the miata are IMO pretty friggin nice, but the race are better with stiff springs.

I found Dan's car with sports and gc coilovers to be very nice. I wouldn't mind having his suspension on my car.

I thought the race shocks were Silver, unless someone got sports and had them revalved to race spec, then yes, they would be yellow. But i'm pretty sure Koni Race is silver in color.

Sam-some Miatas came with Bilsteins from the factory, your's probably didn't.
R package, LE, and maybe a few more, I am not sure. The ones I link'd in, those are off a NB, which means you are getting the better top hats for more travel at the same time. I would pay as much as $300 for that setup.

It pretty much breaks down by price point. How far are you willing to go/spend.

AGX/Ilumina + Lowering springs
Bilstein/Koni + Loweing springs
Bilstein/Koni + Eibach ERS + GC/FCM Sleeves
Bilstein/Koni + Eibach ERS + GC/FCM Sleeves + NB Top Hat mounting solution
Tein Flex
AFCO/Ohlins/FLT-A2/ETC
XIDA <-not out yet.
Penske/any other full blown custom solution.

So basically 500-5000$

I personally went with #4. Lots of people opt for that and then go revalve/shortening, for "extreme" (700+ front) spring rates, but if I was going to do that I would go straight to FLEX.

The above is just the shock, as many others here have mentioned suspension is more then the shock.

Without getting into high dollar custom bits, basically what you want is a tubular front sway, with brace (ala racing beat), adjustable endlinks, and depending on the shape of your stockers, new bushings.

I am of the opinion that if you are going to spend that much money (5k+ on suspension) on a fucking miata of all things, you should have bought a 30k Elise. Without getting into super high dollar custom bits (1000$+ uprights, x$ custom a-arms, etc) a GOOD all around setup should be around 1500-2k. 3k including wheels/tires.

I think the best deal ($/performance ratio) is used flex setup, baring that koni sport + gcc.

Oh I agree. I dont want to spend that much on a suspension. Less then 1000 for sure. #4 looks about right as well, mostly because I want more suspension travel. How much does that setup run?

What are the sleeves for?

Ah I see now. So basically get these bilsteins and the FM springs?

FM springs say they arent made for the stock shock, so i dont know how that will work since technically its an OEM.

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Just quickly looking up prices. Bilsteins go for 143 a pair(from bilstein.com, im guessing these are same as OEM) so thats x 2 = 286 + 249 for FM springs = 545. Not bad at all.

What would happen if I kept stock sways for the time being and just scavenged for some NB top hats?

The coilover sleeves are for ride height adjustment.

Koni's: ~500
GCC's: ~350
NB Tophat: ~200 from FCM.
FCM bumpstops: ~50

You can't just scavenge the tophats, you need a custom nut. Which either has to be CNC'd or bought as a whole from FCM/other places.

I think the bilsteins from bilstein.com might be the HD's not the OEM R-package ones. Which are a crappier shock.

If you can find a set used, not beat to shit, 93LE/94-97R OEM bilsteins plus the other stuff is a good bet, otherwise go with the new Koni's.

Lots of guys run stock sways, you just don't get the max potential. Depending on spring rates chosen, the car might be a bit tailhappy, which is not what you want with a boosted miata, but that is easily fixed by unbolting the rear sway.

<RANDOM CONJECTURE>
NB Shocks might be the ticket with coilovers as the best $/performance ratio as you can run the tophats without any custom nut bullshit, but I KNOW you can't run stock springs as the car is raised over stock height, and I am not sure how low you can go with coilovers while retaining some travel.
</RANDOM CONJECTURE>

I think if the random conjecture were true, someone would have already figured it out. Then everyone would know about it.

to answer some one's question a long time ago, I have FM's new springs, so 318F/233R with kyb shocks. you can find them for a little cheaper on ebay, such as this:

http://cgi.ebay.com/ebaymotors/KYB-A...spagenameZWDVW

then get FM springs and sway bars for $350 total, FCM bump stops/top mounts for around what, $200? haven't seen their site in a while. so whats that, $885? damn I spent a lot on my suspension...but its awesome. you could easily go to les schwab or anywhere else and have them mount your springs on your shocks for real cheap. I got all of mine without a spring compressor except one, and they put that one on for free.

sam, I dont think you will have any problems if you lower your car a bit. Mine is about an inch lower than stock, and I have almost no problems EVER, and there are plenty of shitty roads in la. The car is so short that most things do not cause a problem. I almost never have to pull diagonal riced out civic type moves. Very short speed bumps will fuck me up though, but only if I get overzealous.

Couple of questions.

Could I purchase the Bilstein shocks that come on the NB Sport somewhere online? Anyone know how much they are?

What if I get:

Bilstein shocks
FM Springs
FCM Bumpstops
FM Top hats

Would that be a good upgrade?

Again, the car is 100% street, I just want a bit more feedback. Not concerned about height adjustment, its difficult to get into and out of as it is.

edit: Are the stock top hats reusable?