Track Suspension

[id3379]

Is anyone using sus that's better then the tien street coil overs ? Looking for some super stiff coil overs that can lower atleast 2.5''

Anyone sportin the goods?

[kngrsll]

Is anyone using sus that's better then the tien street coil overs ? Looking for some super stiff coil overs that can lower atleast 2.5''

Anyone sportin the goods?

no one yet, im working on a solution though! We have a really good damper now that will be for sale soon if it isnt now (the tokico HTS) but there are no good spring options. I will keep everyone update as to the spring situation though.

I just ran a track event with the tanabe DF210's, Tokico HTS, and Ultra Racing 23mm rear sway bar, and 195/55/15 star spec direzza tires, and the car drove GREAT!! Way better than i thought it would, and anyone else who drove it, loved it!

If you want another spring option, the Teins are 3kgF,3.5KgR i believe, so that would raise your rear spring rates a little as the DF210's are 3KgF,2.2KgR.

Hope that helps! I love seeing other yaris owners hit the track, this is a surprisingly great little track car!

[id3379]

Thanks for the info

[kngrsll]

Thanks for the info

no problem... another thing, i was looking at the front suspension today, we have quite a bit of shock travel stock. thats really nice to know!

[CASTREX]

Megan Racing / Ksport / BC

All of them have coilovers available for the Yaris... all for under $1K all of them would be able to give you the drop and stiffnes you are looking for.

+tires + rear swaybar+ aggresive aligment

and you are track ready.

The Yaris doesn't really need more than that....

[cali yaris]

There is a coilover thread you should read, instead of us trying to re-create it here:

http://www.yarisworld.com/forums/showthread.php?t=8342

Also, we have new AOE TigerTec springs that are 4k front, 3k rear that are very nice and stiff if you're thinking about separate shocks/struts + spring applications.

[thebarber]

id use megan's on-track...theyre pretty stiff even on full soft

tein basics are way too soft

[id3379]

Thank you garm, great link

thebarber; yah i felt the same about teins

[Loren]

Every street coilover kit has rear springs that are way too soft. I just put a set of 7kg springs on the rear of my car (fronts are at 4k) with the K-Sport kit, that's the kind of rear rate that this car needs and nobody is offering it. I also have the 23mm rear stabilizer bar. When I put the 7k rear springs on, I added some rear camber to keep oversteer in check. The combination is very neutral with almost no understeer, even autocrossing on craptastic Toyo T1R's.

I believe K-Sport is offering their Road Race coilover kit for the Yaris now. Normally, that kit allows specification of custom spring rates. If that's the case with the Yaris kit, that might be a good way to go.

For all-out track use, something like 4kg/8kg would be a good place to start. Add good camber all around (2.5-3 degrees front, 1.5-2 degrees rear) and a good set of tires and you'd really have something.

I haven't tried it yet, but with stiffer front springs (4k might be enough) removing the front swaybar might be the hot ticket. Bear in mind that in a turn, the front swaybar is trying to LIFT the inside front tire... you don't need that. Use the rear roll stiffness (from stiff springs and a rear bar) to control the body roll and allow the front suspension to WORK as much as it can to keep the front tires hooked up. I might try that after I give myself a couple months to get used to the stiffer rear springs.

[cali yaris]

that's the kind of rear rate that this car needs and nobody is offering it.

You can order Silk Road coilovers with any springs rates you want. They normally come 5k/7k. :smile:

[Loren]

You can order Silk Road coilovers with any springs rates you want. They normally come 5k/7k. :smile:
That's not bad. Still a "street bias" though. Probably not bad at all with a factory rear alignment. No wonder people like the Silk Road so much.

[detroiter]

I have the AOE tigertecs on my car paired up with some Tokico HP's and a trd rear sway bar. I can after settling in and getting an alignment, this car handles like a monster. I'm sure if I'd put some better tires on then the stock Bridgestones, that it would be even better. Depending on what your willing to spend, I totally suggest the AOE Tigertec springs paired up with better then stock shocks, preferrably.

[Tamago]

loren!!! where did you get your 7k springs?

oh and.. i spoke extensively with Gordon from Koni tech support today. he has a solution to the rear spring issues that other manufacturers have faced with the xa/xb/yaris style suspension. because of the excellent motion ratio of the rear shocks, converting the setup to eye-to-eye style shocks with adjustable perches will now move the spring from the "inboard" mounting point to a much more "outboard" position. this will allow you to run a "softer" spring and maintain the same ride quality.

i have koni yellows on the way from kngrsll and Ksport rear spring perches/springs as well. next up, getting ground control to sell me sleeves for the front and i think i'll finally have my suspension back up to par.

anyone here interested in a petition to show to Koni North America that Yaris owners want shocks/struts?

[kngrsll]

Loren! you are still around lol... i cant believe your rear spring rates are that high! thats good to know though...

[Loren]

My rear springs are from my old Tein SS Miata suspension. I've been running 4's since I first installed the suspension, never even put the 2.3's that came with the K-Sport kit on the car. I always thought 7kg would be too much because I actually tried them before I put the 4's on. It felt GREAT on the short drive that I took, but since I was prepping to go cross-country and drive on a bunch of unfamiliar race tracks with no time to do any real testing, I didn't want to risk having an oversteery car. So, I went with the 4's.

It wasn't until after I put the 23mm rear bar on and found that I still had to run the rear shocks at near full stiff to get the car to oversteer that I realized the car WANTS a lot more rear stiffness. When I noticed my rear tires were wearing on the outside and begging for more camber, the plan all came together. More rear stiffness, more camber to resist oversteer and even out the tire wear.

The Tein springs are NOT a perfect fit. In fact, they would very likely fall out without the tender springs (that I conveniently had on the shelf from the same SS kit). And they barely fit the K-Sport lower perch. They clunk and creak and stuff, but only my wife cares. :)

I think I've swapped some email with Gordon back when I was running Koni's on my Miata a LONG time ago. Him and Lee Grimes are the main Koni gurus in the US, I think.

I wondered if the upper shock mounting point was beefy enough to support a true coilover setup in the rear. That would be interesting, for sure... and it does appear that the motion ratio would require less spring that far back on the axle assembly. Putting an actual suspension mounting point there might actually create a need for that rear shock tower brace!

BTW, Tamago, I used your washer trick on the rear hubs. $2 for some SS washers, a couple minutes at the grinder and now I have about 2 degrees of camber back there!

Kngsrll... I have been considering dropping YW. Sometimes I just don't have the patience for it. Most of the time, really.

Couldn't resist a "track suspension" thread, of course.

[Tamago]

loren, if you have Gchat, please give it to me before you leave!

and if you want to sell your 4kg's let me know, Ksport refused to send me anything but 2.2K with my rear perches :(

[Loren]

Tamago, my email address is no secret... write it down somewhere, that's the best way to reach me.

With your fab skills, you should be able to use a standard spring and just spin up some perch adapters for it. Might take some experimentation to get it to work right.

The Tein springs that I have wouldn't work for you without the Tein tender springs, and I don't have another set of those. The tender spring allows the spring to work with the odd angle that the lower spring perch takes as the suspension droops.

Hey! How is Silk Road doing 7kg rear springs? Anybody got photos of that setup?

[Tamago]

Tamago, my email address is no secret... write it down somewhere, that's the best way to reach me.

With your fab skills, you should be able to use a standard spring and just spin up some perch adapters for it. Might take some experimentation to get it to work right.

The Tein springs that I have wouldn't work for you without the Tein tender springs, and I don't have another set of those. The tender spring allows the spring to work with the odd angle that the lower spring perch takes as the suspension droops.

Hey! How is Silk Road doing 7kg rear springs? Anybody got photos of that setup?

once the perches get here, i'll most likely be doing exactly that, already have a 3" plug of 6061 waiting at the lathe!

[cali yaris]

I'll take pics of the Silk Roads on my car.

[largeorangefont]

You will need more than the useless rear shock bushing brace if you go with a coilover setup on the rear shocks.

you could groove the rear shocks and run compression rings for coilover sleeves. That is what I run on my Cobra in the rear.

With a stiff rear sway bar and coilovers you could punch right through the upper shockmount. You would at least need delrin upper bushings and possibly weld or bolt on a steel plate for reinforcement.

[Tamago]

You will need more than the useless rear shock bushing brace if you go with a coilover setup on the rear shocks.

you could groove the rear shocks and run compression rings for coilover sleeves. That is what I run on my Cobra in the rear.


eye-to-eye shocks can be modified to accept spring perches :) if my Ksport perches don't work out that'll be my next step.

[largeorangefont]

eye-to-eye shocks can be modified to accept spring perches :) if my Ksport perches don't work out that'll be my next step.

Yea that would make things significantly easier, you would probably have to get them revalved for this application, but that is not horrible.

[Loren]

You will need more than the useless rear shock bushing brace if you go with a coilover setup on the rear shocks.

you could groove the rear shocks and run compression rings for coilover sleeves. That is what I run on my Cobra in the rear.

With a stiff rear sway bar and coilovers you could punch right through the upper shockmount. You would at least need delrin upper bushings and possibly weld or bolt on a steel plate for reinforcement.

Yeah, I was thinking the same sort of thing. That upper mount wasn't made to carry any weight. Even putting in a reinforcement at the top could just be moving the weak point to lower on the tower where something else will bend or break under fatigue. Now, if the car had a full rollcage and you could tie into that... that could work.

[kngrsll]

You will need more than the useless rear shock bushing brace if you go with a coilover setup on the rear shocks.

you could groove the rear shocks and run compression rings for coilover sleeves. That is what I run on my Cobra in the rear.

With a stiff rear sway bar and coilovers you could punch right through the upper shockmount. You would at least need delrin upper bushings and possibly weld or bolt on a steel plate for reinforcement.

do you have a link for this process? If not, could you explain more about grooving the shocks?

My idea is similar i think, i thought about simply welding on a collar to set the spring perch on.

[kngrsll]

Yeah, I was thinking the same sort of thing. That upper mount wasn't made to carry any weight. Even putting in a reinforcement at the top could just be moving the weak point to lower on the tower where something else will bend or break under fatigue. Now, if the car had a full rollcage and you could tie into that... that could work.

sounds like a great excuse to me :rofl:

[Tamago]

Yea that would make things significantly easier, you would probably have to get them revalved for this application, but that is not horrible.


http://www.jegs.com/i/Koni/610/8216-2027/10002/-1

[Tamago]

do you have a link for this process? If not, could you explain more about grooving the shocks?

My idea is similar i think, i thought about simply welding on a collar to set the spring perch on.

i can groove them at my shop :)

however, Gordon at koni does not recommend doing this, as the outer shell of most shocks is not thick enough to withstand grooving/welding unless already equipped in such a way.

[largeorangefont]

do you have a link for this process? If not, could you explain more about grooving the shocks?

My idea is similar i think, i thought about simply welding on a collar to set the spring perch on.

You dont want to be welding to shock bodies.

Pages 4-7 deal with the grooved shock body and the spirolock ring that hold on the coilover sleeve.

http://www.maximummotorsports.com/content/install/pdf/rear_susp/MMCO-4r6.pdf

[kngrsll]

i can groove them at my shop :)

however, Gordon at koni does not recommend doing this, as the outer shell of most shocks is not thick enough to withstand grooving/welding unless already equipped in such a way.

really? shit... what about a sleeve with the top filled in and a hole drilled into the top for the shaft. So the sleeve fits down over the shock, and the top (rim?) of the collar goes over the top of the shock where the shaft passes through the hole. Then, you can have another collar on the bottom of it where you can slide a perch onto it.

Does that make sense at all?

[largeorangefont]

i can groove them at my shop :)

however, Gordon at koni does not recommend doing this, as the outer shell of most shocks is not thick enough to withstand grooving/welding unless already equipped in such a way.

Agreed. You woudl need to check with the shock manufacturer to see if this is even viable.

It is an easy process to groove the shock bodies though.

[kngrsll]

You dont want to be welding to shock bodies.

Pages 4-7 deal with the grooved shock body and the spirolock ring that hold on the coilover sleeve.

http://www.maximummotorsports.com/content/install/pdf/rear_susp/MMCO-4r6.pdf

thanks!

i like that idea alot...

[largeorangefont]

really? shit... what about a sleeve with the top filled in and a hole drilled into the top for the shaft. So the sleeve fits down over the shock, and the top (rim?) of the collar goes over the top of the shock where the shaft passes through the hole. Then, you can have another collar on the bottom of it where you can slide a perch onto it.

Does that make sense at all?

Shocks are not designed to be load bearing suspension components usually, so that probably would not really work either. If the shock was beefy enough to do that, you could groove it anyway.

[largeorangefont]

Yeah, I was thinking the same sort of thing. That upper mount wasn't made to carry any weight. Even putting in a reinforcement at the top could just be moving the weak point to lower on the tower where something else will bend or break under fatigue. Now, if the car had a full rollcage and you could tie into that... that could work.


Yea.. the shock mount might need to be boxed in completely. If I was going this route, that is what I would do.

[kngrsll]

what do you guys think of using these? you can select rate, but probably cant adjust height though. I think i measured the rear spring to be 5 1/2" in diameter.

http://www.dansracingsupply.com/AFCO.htm

http://www.afabcorp.com/AFCO_Dynatech_USbrake/merchant.mvc?Screen=CTGY&Store_Code=A&Category_Code=ct_Conventional

So if you can figure out what spring will allow you to have a decent height, and then you can get collars for the front, you are good to go. you wont have rear height adjustability, but you could use a good strong rate.

[Tamago]

Gordon at koni said 9" would be good for my setup, and i'd imagine that a 9" travel shock would work for y'all in the back as well

[kngrsll]

Gordon at koni said 9" would be good for my setup, and i'd imagine that a 9" travel shock would work for y'all in the back as well

got any aftermarket springs around you can measure?

[Tamago]

got any aftermarket springs around you can measure?

not currently, i'm at home :)

[kngrsll]

does that sound doable though? i know normally, you can trim up to 1 coil off a spring and without affecting its rate, so you could do that if you needed to, or if its too short, you can spring rubber to raise the height.

[Tamago]

does that sound doable though? i know normally, you can trim up to 1 coil off a spring and without affecting its rate, so you could do that if you needed to, or if its too short, you can spring rubber to raise the height.

i'm currently on xB Tein S techs with one coil removed. car is stiff, but strut/shock rates are garbage (stock)... i traded my coilovers for boost back in late 2007

[Loren]

Here's a tip: If you're looking for a shock that's designed to be a "load bearing member", look at Miata shocks. A lot of mechanics think they are struts because that's what they look like, but due to the Miata's double-wishbone suspension, they carry no side load.

Anyway... look at something like the rear KYB AGX for a 94-97 Miata. 8-position damping adjustment, and the spring perch can be hammered off to reveal a retaining ring. You can put anything you want around that shock to be supported by that ring. Of course, you'd still have to deal with whether or not the Yaris rear upper shock mount is sufficient to support the weight of the car.

I like the idea of fitting larger diameter race springs in place of the stock rear springs. I almost made that suggestion a while ago. There are several diameters available, circle track guys use them for building those old school stock cars. Just need to figure out what diameter will fit, or make some perch adapters to make something fit.

BUT, the problem comes when you want a stiff spring. Let's take my 7kg for example. I think better in pounds (and most non-JDM race springs will be spec'd in pounds, anyway), so let's call it 400 lb/in. The stock springs are something like 120 lb/in. At stock height, let's say that the car has 4 inches of compression travel and 4 inches of droop travel (which probably isn't too far off). So, the spring needs to be able to extend more than 4" under suspension droop to avoid falling out of the perch when you're playing Dukes of Hazzard jumping over RR tracks or lifting a rear wheel while autocrossing.

Stock springs are about 14" long (I'm guessing), and probably compress to about 4", giving them 10" of compression before coil binding (which a stock suspension should be designed to never do). With 8" of total suspension travel, that means that at full compression there's probably an inch left to compress, and at full droop probably an inch of extension left to keep tension on the spring in its perches. Cool.

Now, let's put in a 400# spring. First of all, if we don't change the length of the spring, the height of the rear of the car is going to go WAY up. Just to keep the same height, we need to shorten the spring. With each corner of the rear of the car weighing about 460# (2300 x half x 40%), the stock spring was compressing (assuming 1:1 motion ratio just for the sake of this discussion) 460/120 or 3.8" (hey, there's our 4" of droop travel!). The 400# spring will only compress 1.15", so the 400# spring needs to be about 2.75" SHORTER just to retain stock ride height.

But... at stock ride height, we still have 4" of droop travel. Is the 2.75" shorter spring going to stay in the perch at full droop? To complicate and amplify this problem, who runs stock ride height when they have a modded suspension? Subtract 2" from the ride height, which ADDS 2" to the droop height... ugh. What's holding those springs in now?

There are a couple solutions to this problem. One is with the shocks. Shorter shocks with less droop will limit how far the suspension can droop, possibly more than the factory limit. I think most coilover shocks (especially those intended for the rear of a FWD car) are designed for this, and probably have a "reverse bump stop" built into them. You can't fully rely on this, though, as you do need SOME droop travel for the suspension to work properly.

The other solution is to use a "tender" spring (this is what I did), which is a very low rate spring that stacks on top of (or below, doesn't matter) the main spring and is fully compressed under the weight of the car. At rest, it essentially acts as a spacer. But, when the weight comes off of that corner and the suspension droops, it expands with enough force to keep itself and the main spring retained in the perches. You'll find a lot of so-called "progressive" aftermarket springs are done this way. The coils at one end will be so closely spaced that they are fully compressed under the weight of the car. That's why.

So, you can go with either a super-low rate tender spring like I have... I think the rate is something like 50#, and it compresses flat to about 1/2" height, or you can go with a low rate "real spring" that won't compress as flat. You can either get couplers to fit between the two springs and keep them together, or you can simply weld the two springs together. As long as you go with a tender or "helper" spring that is a low enough rate to be fully compressed under the weight of the car, you can figure it as a "spacer" for static ride height, and figuring the length of the main spring won't be too hard. If you try to build a truly "progressive" spring stack where both springs are still in play, then things get more complicated and adjustable perches make life MUCH easier.

Have I confused anyone yet? I think I confused myself.

The important thing is, for safety, always be sure that your spring has enough tension under full droop to stay in its perch. That can sometimes be a challenge.

[kngrsll]

Ok, totally got what you are thinking Loren...

Now there are also some other issues. In studying this issue, it appears that our "stock" rear springs are "double pig tail" meaning they are fat in the middle, and get smaller near the ends. Wierd terminology, i know. Anyways, the Tanabe springs are 5.5" in diameter in the middle, and about 2.5-2.75" (measured on the car). When the car was jacked up and the rear was fully unloaded, the spring was sitting at 12". it was not able to be pulled out, so there must be a little more length in it, but not much, i would guess its a 12" spring out of the car, its just tight in there. Now there are also two rubber pieces in the back on the top and the rear, so removing one or both of those can reduce the height somewhat. So the free length of the spring must be about 12" to stay in place if the rear suspension becomes fully unloaded, correct?

So what is available for the aftermarket NASCAR folks? Well they carry 2 1/2" or 2 5/8" diameter springs in nearly any length and spring rate you can imagine. Now, if the pig tails end up at that diameter, you could use them i imagine. I would like to try and stay somewhat closer to stock, that can be tried later. So i looked at double pig tail springs, and most of them were 7" inner diameter in the middle, and were very soft, so they are out. Next, i found single pig tail springs. They are flat on the bottom at 5.5" diameter and curl up to the "pig tail" of 2 5/8". They do not come in as many lengths (11, 12, 14 i think is what i came across.) They also don't have as many rates, they highest rate was 300# (as opposed to nearly 1500#s for the others!!) but they are stiff enough for what i want. they come in increments of 25 and 10 #'s.

The reason i believe the single pig tail will work is because the top of the spring is tight, it tapers in like the "pig tail" springs. The bottom though does not, the rear spring seat is a flat tray that is about 7" in outer diameter. Thus i think a flat bottomed, single pig tail spring (5.5" tapering up to 2 5/8") will work. Now the length of the spring i measured on my car is 12", but was still loaded in, so may be a bit more compressed (maybe an inch or two). Remember there are the two rubber insulators on the top and bottom of the spring as well (easily an inch in addition.)

Now we are back to the problem with the spring rates. The length is correct, but the spring may cause the car to sit higher than it needs to. For an easy fix, the rear insulators can come out. As well, you could trim part of the spring off. Or you could just use lower rates then you really want to. Now the rear spring i have now is a Tanabe, so it is a 2.2kg or 123 lb spring. To match the front, you only need to go to 175, that gives you a matching rate front and rear, shifting the balance toward the rear. I think that will easily work. Now what about higher rates? no idea. I would also like to try a 275 lb spring (to make it 175F/275R) to see how it would turn out. This spring may need to have part of a coil trimmed off, while the 175 may actually need a spring rubber to raise it.

So i ordered two sets of springs ($50 a piece with a $40 discount for ordering 4) to try out. i got 12" free length single pig tail springs, 175# and 275#. If they dont work, ill send them back and try something else. After i try this out, we can go from there.

Whew, longest post i think ive ever made lol, hope it helps (and works!)

[kngrsll]

http://www.stockcarproducts.com/

http://www.stockcarproducts.com/hyper2a.htm

[CASTREX]

My head is gonna blow....

...Subscribed

[Loren]

I'm glad someone grasped what I was saying... I really felt like I was rambling. I literally had an awful headache at that very moment and wasn't sure I was making sense at all!

The problem with using 2.5" ID springs in the stock location is that the way the rear axle assembly moves, the lower spring perch does not come up in a straight line. It's fairly level at rest (at stock ride height), but as the suspension compresses or droops, that lower perch takes an angle compared to the upper perch, this makes the spring want to bend. Small diameter springs don't like to do that. The larger diameter spring will help with that, as will the pigtailed end.

2.5" ID springs are available in any size and rate you can think of, and they're dirt cheap (relatively speaking), but I'm not sure they'd work well for this application, unfortunately.

[kngrsll]

I'm glad someone grasped what I was saying... I really felt like I was rambling. I literally had an awful headache at that very moment and wasn't sure I was making sense at all!

The problem with using 2.5" ID springs in the stock location is that the way the rear axle assembly moves, the lower spring perch does not come up in a straight line. It's fairly level at rest (at stock ride height), but as the suspension compresses or droops, that lower perch takes an angle compared to the upper perch, this makes the spring want to bend. Small diameter springs don't like to do that. The larger diameter spring will help with that, as will the pigtailed end.

2.5" ID springs are available in any size and rate you can think of, and they're dirt cheap (relatively speaking), but I'm not sure they'd work well for this application, unfortunately.

Thats makes sense... i did notice that when i was down there.

now does my logic for the single pig tailed springs seem sound then?

[Tamago]

how about conical top/bottom mounts? like 2" conical top and bottom. that'll give you 4" of insurance, keeping the spring IN place for those airborne jumps? i believe the MKIV VW guys have something like this.

[Loren]

now does my logic for the single pig tailed springs seem sound then?
Certainly worth a shot. I'd put the pigtail end down if possible, since the upper spring perch is the one that's fixed.

[kngrsll]

Certainly worth a shot. I'd put the pigtail end down if possible, since the upper spring perch is the one that's fixed.

i think the opposite may be better. The top fixed perch seems a bit smaller than 5.5" just off the top of my head, so i think the pig tailed end would fit better there, while the bottom perch is just wide and flat.

As an alternative, I think it would be nice to come up with a way to secure the spring down flat perhaps if that set up must be done. Maybe drill a couple holes and run a clamp or something to keep it down, i dunno.

Care to expand on your idea Joel?

[Tamago]

i think the opposite may be better. The top fixed perch seems a bit smaller than 5.5" just off the top of my head, so i think the pig tailed end would fit better there, while the bottom perch is just wide and flat.

As an alternative, I think it would be nice to come up with a way to secure the spring down flat perhaps if that set up must be done. Maybe drill a couple holes and run a clamp or something to keep it down, i dunno.

Care to expand on your idea Joel?

the silk roads utilize the weephole to bolt down the perch. can't remember if it was top or bottom, get RussellTehPirate to expound..

and i'm not the same chassis so we're talking mcintosh/fuji apples here...

as far as making conical mounts, what about grabbing some energy suspension urethane parts? i'm sure we can figure out SOMETHING that's already a stock part + a bolt/washer/nut...

[kngrsll]

the silk roads utilize the weephole to bolt down the perch. can't remember if it was top or bottom, get RussellTehPirate to expound..

and i'm not the same chassis so we're talking mcintosh/fuji apples here...

as far as making conical mounts, what about grabbing some energy suspension urethane parts? i'm sure we can figure out SOMETHING that's already a stock part + a bolt/washer/nut...

i like the idea of bolting down the spring/perch! nice...

i'm still not getting the conical mounts. i did a quick google and didnt really find anything useful. do you have a pic or example or something?

[Tamago]

i like the idea of bolting down the spring/perch! nice...

i'm still not getting the conical mounts. i did a quick google and didnt really find anything useful. do you have a pic or example or something?

ok, the stock spring mounts have a small "raised" portion in the middle to help retain the spring, right?

so why not make a urethane "cone" that mounts to that same raised mount, kind of like a bump stop, that keeps the spring from falling out.. let me try paint+touchpad on my laptop brb

[kngrsll]

ok, the stock spring mounts have a small "raised" portion in the middle to help retain the spring, right?

so why not make a urethane "cone" that mounts to that same raised mount, kind of like a bump stop, that keeps the spring from falling out.. let me try paint+touchpad on my laptop brb

oh, i think i get it! another analogy is like a cup for the spring, right?

[Tamago]

http://i40.tinypic.com/10rs8id.jpg

touch pad + laptop + msPaint = this shitty drawing. the conical part is in "red" and my spring is orange. .. up is up and down is down.

[kngrsll]

http://i40.tinypic.com/10rs8id.jpg

touch pad + laptop + msPaint = this shitty drawing. the conical part is in "red" and my spring is orange. .. up is up and down is down.

Awesome! i think i get it....

[Loren]

Not sure how you'd attach something like that, especially at the top.

The bottom perch you can definitely bolt something to, the K-Sport kit does that, too.

[Tamago]

Not sure how you'd attach something like that, especially at the top.

The bottom perch you can definitely bolt something to, the K-Sport kit does that, too.

WINDO-WELD AT THE TOP?

[Loren]

WINDO-WELD AT THE TOP?

I wouldn't expect that to hold against a stiff spring that's being bent in it's perch. Maybe if you happened to have a completely loose spring it would keep things aligned as the car came down?

If you want simple... old swing-axle cars (like my Spitfire, old VW bugs and Corvairs) sometimes used "droop limiters". They used them for a different reason, on those cars, when the axle droops, camber goes positive, and if you come down on it quickly while the camber is way positive... it's not pretty.

But, all you need is a strap or cable or chain or something to keep the axle assembly from falling low enough to unseat the spring. Sort of the same thing we're already doing with the shock. That's exactly what the shock does at full extension, it limits the droop of the axle. Adding a droop limiter takes that load off of the shock, which is probably a good thing.

[Tamago]

I wouldn't expect that to hold against a stiff spring that's being bent in it's perch. Maybe if you happened to have a completely loose spring it would keep things aligned as the car came down?

If you want simple... old swing-axle cars (like my Spitfire, old VW bugs and Corvairs) sometimes used "droop limiters". They used them for a different reason, on those cars, when the axle droops, camber goes positive, and if you come down on it quickly while the camber is way positive... it's not pretty.

But, all you need is a strap or cable or chain or something to keep the axle assembly from falling low enough to unseat the spring. Sort of the same thing we're already doing with the shock. That's exactly what the shock does at full extension, it limits the droop of the axle. Adding a droop limiter takes that load off of the shock, which is probably a good thing.

1/8" cable + a turnbuckle would do this quite nicely. that's a good idea.. i think i'll just do this lol

oh, and panel bonding epoxies are EXTREMELY strong, in most cases is replacing welding for bodymen.

[largeorangefont]

I already brought this up a couple weeks ago in the Tokico HTS thread.

You can use a tow strap to limit down travel, and it will be lighter than all that extra crap to hold the spring in. Pro Comp makes straps in various lengths for off road trucks.

I was also thinking of a bolt in perch on the torsion axle, but since there is a hole in the middle, make the lower perch adjustable.

[kngrsll]

But, all you need is a strap or cable or chain or something to keep the axle assembly from falling low enough to unseat the spring. Sort of the same thing we're already doing with the shock. That's exactly what the shock does at full extension, it limits the droop of the axle. Adding a droop limiter takes that load off of the shock, which is probably a good thing.

great idea, someone brought it up last week i think

I already brought this up a couple weeks ago in the Tokico HTS thread.

You can use a tow strap to limit down travel, and it will be lighter than all that extra crap to hold the spring in. Pro Comp makes straps in various lengths for off road trucks.

I was also thinking of a bolt in perch on the torsion axle, but since there is a hole in the middle, make the lower perch adjustable.

LOL yep, thanks for the suggestion!

so now, we can use a shorter spring for a higher rate, as long as we use a strap to shorten the droop! 400 lb rear springs, here we come?

[largeorangefont]

great idea, someone brought it up last week i think



LOL yep, thanks for the suggestion!

so now, we can use a shorter spring for a higher rate, as long as we use a strap to shorten the droop! 400 lb rear springs, here we come?


If you can find a 400# spring of the right diameter and length, you could do it now with no perches. You will definately need straps for those HTS shocks.

Assuming the spring can sit on the stock perches,you can roughly figure out the length needed measuring the length of your current spring with the car on the ground. Then take the weight of the car, and the weight distribution, and figure out roughly how much weight is on the rear tires. Remember you have 2 rear springs so you want to devide this weight by 2. You know it takes 400lbs to compress the spring 1 inch. Do the math and you will have your approximate free length. It should only be around an inch more than the measurment of the compressed spring. There is not a lot of weight back there.

Strap placement will be tricky, so you will need to figure that out. You would set the droop so that the spring could never fall out if the rear suspension were to become unloaded or if an inside rear tire left the ground in a corner. That type of full articulation is actually more droop than if both rear wheels were off the ground. If you set the droop such that the spring is unloaded, but still touching the perches, you should be fine. You have the "dome" of the perches to hold the spring in and give you a little extra buffer in a 3 wheel situation.

Unfortunately with stiff spring like that you wont be left with much rear droop. This is fine for the racetrack, but may be a little harsh on the street.

[Tamago]

There is not a lot of weight back there.


say what, 40% of 2300lbs? 920lbs total, split that and you have 460 lbs each spring.

so you'd get 1.15" of compression at rest..

[Tamago]

Unfortunately with stiff spring like that you wont be left with much rear droop. This is fine for the racetrack, but may be a little harsh on the street.

if i cross from a parking lot to the street at a diagonal angle, i'm two-wheeling every time. i've gotten used to it, but have had strangers at the gas station comment on it lol

[Loren]

I'd add the caution here that this might not be the smoothest riding street suspension over big bumps. With a 400# spring, you're not going to have much more than 1" of compression under the weight of the car. That means that your droop limiter has to retain the spring at a mere 1" of droop. Fine for competition, but possibly rough for the street.

[Loren]

Funny... Big Orange and I are saying the same things.

[Tamago]

I'd add the caution here that this might not be the smoothest riding street suspension over big bumps. With a 400# spring, you're not going to have much more than 1" of compression under the weight of the car. That means that your droop limiter has to retain the spring at a mere 1" of droop. Fine for competition, but possibly rough for the street.

i should have kept the motion ratio in mind when doing my calcs.

rough motion ratio is .7, so you'd actually compress 1.64" at static.

[largeorangefont]

Funny... Big Orange and I are saying the same things.

We generally do.:headbang:

[largeorangefont]

say what, 40% of 2300lbs? 920lbs total, split that and you have 460 lbs each spring.

so you'd get 1.15" of compression at rest..

Yea if that...

[largeorangefont]

if i cross from a parking lot to the street at a diagonal angle, i'm two-wheeling every time. i've gotten used to it, but have had strangers at the gas station comment on it lol

It is not that, it is dips at speed we are talking about. Potholes are a good example. At speed a softer, longer travel suspension would allow the wheel to drop into the hole and on hole exit the suspension would absorb the impact with bump travel.

Lets say you hit a pothole with yout right rear. With no droop the entire weight on that wheel falls into the pothole, you feel the car drop into the hole. Upon exit of the pothole, that wheel would reload the left front wheel, and you would feel the wheel and car lifting up and out of the hole. It would feel very jaring.

[Tamago]

It is not that, it is dips at speed we are talking about. Potholes are a good exampl. A softer, longer travel suspension would allow the wheel to drop into the hole and on hole exit the suspension would absorb the impact with bump travel.

Instead the entire weight on that wheel falls into the pothole, and pushes that weight back up upon exit of the pothole. It would be very jaring.

just drive really fast and float over the potholes? ;)

[Loren]

if an inside rear tire left the ground in a corner
If? This is a situation that anyone who's going this far with their suspension needs to PLAN on. The young guys working course at the BMW club autox I went to last weekend were calling me "tripod" at the end of the day!

The inside rear wheel will be in the air more than it's on the ground unless you're going straight.

[Tamago]

If? This is a situation that anyone who's going this far with their suspension needs to PLAN on. The young guys working course at the BMW club autox I went to last weekend were calling me "tripod" at the end of the day!

The inside rear wheel will be in the air more than it's on the ground unless you're going straight.

which is kind of unfortunate as it leaves you with 3/4 of your total grip..

[largeorangefont]

which is kind of unfortunate as it leaves you with 3/4 of your total grip..

There is no weight on that tire anyway in that situation. It will last longer if it is in the air. :)

[largeorangefont]

If? This is a situation that anyone who's going this far with their suspension needs to PLAN on. The young guys working course at the BMW club autox I went to last weekend were calling me "tripod" at the end of the day!

The inside rear wheel will be in the air more than it's on the ground unless you're going straight.

You are right, how silly of me. It should look like an old GTI out there.

[Loren]

It is not that, it is dips at speed we are talking about. Potholes are a good example. At speed a softer, longer travel suspension would allow the wheel to drop into the hole and on hole exit the suspension would absorb the impact with bump travel.

Instead the entire weight on that wheel falls into the pothole, you feel the car drop into the hole. This takes weight off the opposite front tire and slams that weight back up and onto the opposite front again upon exit of the pothole. It would feel very jaring.

The solution to that would be a progressive spring, or a stack of springs designed to be progressive. I figured out how to do this on my Miata, but ultimately decided it was too expensive to bother with. You have to buy two springs instead of just one, and then you have to buy the couplers to go between them (unless you're really confident that your math is correct, then you could just weld them together).

For the back of the Yaris, if you did something like stacking a 6" 400# spring with a 2" 200# spring, the low rate spring would be mostly compressed under the weight of the car and as soon as you entered a turn, the outised spring would coil-bind and give you the 400# rate that you want for cornering. The inside spring would extend, giving you the full effect of the two springs, which nets a nice, soft 133# rate that would be in effect when that wheel came down to smooth things out.

Ground-Control sells the springs you'd need to do that if you wanted to go with 2.5" ID springs.

[Loren]

which is kind of unfortunate as it leaves you with 3/4 of your total grip..
Yes and no. You're optimizing the grip at the front of the car where you need it by taking weight off of the rear of the car. If you want that extra 1/4 of grip that you "lost", run wider tires in the front!

You're not really losing any grip, though. The overall cornering potential of the car goes up. You're taking grip away from the rear where it wasn't needed and transferring it to the front where it was.

[Tamago]

Ground-Control sells the springs you'd need to do that if you wanted to go with 2.5" ID springs.

ground control utilizes eibach :) so you may be able to source them cheaper thru someone else?

[largeorangefont]

The solution to that would be a progressive spring, or a stack of springs designed to be progressive. I figured out how to do this on my Miata, but ultimately decided it was too expensive to bother with. You have to buy two springs instead of just one, and then you have to buy the couplers to go between them (unless you're really confident that your math is correct, then you could just weld them together).

For the back of the Yaris, if you did something like stacking a 6" 400# spring with a 2" 200# spring, the low rate spring would be mostly compressed under the weight of the car and as soon as you entered a turn, the outised spring would coil-bind and give you the 400# rate that you want for cornering. The inside spring would extend, giving you the full effect of the two springs, which nets a nice, soft 133# rate that would be in effect when that wheel came down to smooth things out.

Ground-Control sells the springs you'd need to do that if you wanted to go with 2.5" ID springs.

I have not taken any measurments, but I dont think there is enough room to do that with 2.5 ID springs as we would need perches as well. I think the whole thing would coilbind over bumps, which is fixing one problem and creating another. I would rather have a droop issue than an compression issue. I have no problems living with the horrible street manners of a track spring and damper setup however.

That would absolutely solve the problem if there was room to make it to work.

[Loren]

That would absolutely solve the problem if there was room to make it to work.
Nah, I don't have much problem with it, either. :) I just run the rear shocks softer on the street and call it good.

I just wanted to throw that out there as an example of what can be done if a person were so motivated.

[largeorangefont]

ground control utilizes eibach :) so you may be able to source them cheaper thru someone else?

Hypercoils may be cheaper.

I used to know a place that sold lightly used springs from race cars, eibach and hypercoils for cheap. I'll see if i can dig it up. They wanted like $30 per pair.

[largeorangefont]

Nah, I don't have much problem with it, either. :) I just run the rear shocks softer on the street and call it good.

I just wanted to throw that out there as an example of what can be done if a person were so motivated.

I dont have that kind of motivation.

[kngrsll]

wow, this thread really took off! Ok, ill read and contribute if i can, but i have a ton of work to do tonight!

[Tamago]

well, after having Steve at Ground control dick me around for 3 days like he was gonna actually be helpful, he gives me a canned-bullshit "we no longer carry an application for your vehicle" answer. i'm now stuck with Ksport rear perches/springs on special order, and nothing for the front of my car.

thanks again, ground control. you've dicked me over for the last time. i'm again reminded why i quit doing business with you back in 2003

[kngrsll]

well, after having Steve at Ground control dick me around for 3 days like he was gonna actually be helpful, he gives me a canned-bullshit "we no longer carry an application for your vehicle" answer. i'm now stuck with Ksport rear perches/springs on special order, and nothing for the front of my car.

thanks again, ground control. you've dicked me over for the last time. i'm again reminded why i quit doing business with you back in 2003

they wont even sell the front set (that had NO issues??)

[Tamago]

they wont even sell the front set (that had NO issues??)

per Steve,

"we don't have the spec sheet on these parts"

what kind of fly by night company doesn't keep drawings for past products? simply retarded.

it looks like i'll be doing this:

http://qa1.thomasnet.com/item/motorsports-circle-track-accessories/coil-over-kits/ck1971c?&seo=110&plpver=1001

[kngrsll]

per Steve,

"we don't have the spec sheet on these parts"

what kind of fly by night company doesn't keep drawings for past products? simply retarded.

it looks like i'll be doing this:

http://qa1.thomasnet.com/item/motorsports-circle-track-accessories/coil-over-kits/ck1971c?&seo=110&plpver=1001

thats really suprising... oh well...