bilstein alum perch + ebay coilover sleeve + 6'' spring?
 

Ok, so what are your thoughts on using the stock Bilstein aluminum perch (the one meant for the stock style springs, along with a ebay coil over sleeve set on that and using 6'' springs instead of 7'' to offset the loss in height adjustment?

Just brainstorming here...



Also.. is there any extra adapter needed on the top of the spring to work properly with the 2.5'' race springs and the stock hats?

Brain has run Ebay coilovers just sitting on top of the stock Bilstein perch; he posted a picture of that setup within the last month or so. My only concern with running the 6" springs would be if the selection/pricing is more limited in 6" 2.5OD springs than in the 7". How much are you trying to lower the car from stock??

Ideally 4.25/4.75 from the pinch weld to the ground (about 12''-12.5'')

From a performance point, will the 6'' springs hurt me?

What kind of spring rates?

There have been several recent threads on all this, some with lots of math and explanations.

I forget which perch seat the Bilstein compares to on the Koni, but if you run high enough rates, you may need 6" springs to get to that height since they'll compress less. On the flip side of that coin, you will probably want high spring rates for such short springs to avoid coil bind.

I think the Billie perch isn't as low as the lowest Koni groove (probably closer to middle), so you'll have a little less room to play than Braineack.

I know the info is there and I've read all of it. The problem is, there is no straight definitve answer when it comes to the Bilstiens. Some people say go with teh GC... while those that have the GC say they fit terrible. Then there are the ebay coilover guys who swear by them but others say to stay away. And no one has run the ebay coils ON the bilstein alum perches and can say what ride height they were able to get.

There is a lot of info on the Konis, just not the Bilsteins.

I'll be running 550/350 rates.

with those rates you could might get away with 6"

I ran 550/300 at 7" F/R the lowest I could get the front was 12.5" / 12.75 " with konis on the lowest perch with the collars resting on the perch...

with 400/250 I'm running 7" | 8"

There's a pretty good thread on m.net, but, I'd be worried about coil bind

Brain... how did you like those rates?

H&R makes 6'' springs. And a few dirt track websites sell some as well..

I ran 450/350 6" springs on ebay collars no bind, my dad has the same setup...no problems

Did you have the sleeves resting on the perches?

Also, was the car driven hard?

My Dads are on the perches and mine were on the c clip. IDK if you consider NASA TT hard but I did that with this setup, no baja racing though.

Ebay springs 350/450, giant sway bars, and 15x7 +25's.

http://inlinethumb19.webshots.com/13...600x600Q85.jpg


Why do I feel like falcon punching you everytime you post. Have you ever ran a 6" spring? Have you ever ran an ebay collar/spring? Have you ever made your own coilover setup from scratch? Have you ever owned a turbo miata?

That's a good comparison but I'm driving an NA not NB. I'm about half way through the thread on m.net right now. I found it a while ago but never really read the whole thing.

I'd consider NASA hard.. just wanted to know if it was tracked or street driven basically. And if you didn't have issues with the 5.5'' coils binding at softer rates than I plan to run I'm sure I'll be just fine with the 6''. The ONLY thing I'm someone concerned about is unloading the spring completely at full droop and causing the spring to shift off the perch.

It just seems like SO much info to sift through just for a simple answer of what an NA with ebay collars and 6'' springs can be lowered to.

I'm super sick of all the one sentence answers from internet warriors when I'm actually trying to find proper information.

http://i292.photobucket.com/albums/m...alconPunch.jpg

Are you losing some height adjustment because the NB perch is curved/angled? Can't you just use the NA Bilstein or use the NA Bilstein perch on your NB Bilsteins since the shock bodies are the same?

Not really sure what I'm talking about.

Shock bodies are not the same.

NB shock is almost and inch longer, and the perch groove is higher as well.



All of Brain's calculations are based on the lowest OTS perch you'll find, the lowest groove on an NA Koni. I've done the eBay QA1 setups on both Konis and Bilsteins, and we've compared notes....with high spring rates you'll want 6" springs or not be able to get below 12.5".

Using the 5.5" springs that come with the eBay kit you can nearly slam it on any shock, except the Tokicos apparently with the additional upper ring on the perch stamping.

For the spring rates OP is planning, and how low he wants to go he almost certainly needs 6" springs, especially on the Bilsteins.

my 7" 550s were sitting at 12.5" and had a little room to go lower on stock NA tophats...I have pictures to prove it:

http://www.boostedmiata.com/gallery2...2/DSC_0034.JPG



and rears with 330 7" on middle perch adjusted about .50" off perch:

http://www.boostedmiata.com/gallery2...2/DSC_0035.JPG



That's 12.5" front and 12.75" rear, angles make it hard to read exact numbers.

I'm pretty sure 6" at 550 wouldn't be any issue for bind.

So for a NA Bilsteins (R pkg), can you run 7" springs and still get 12-12.5" w/ 500/325 rates? Or are 6" still necessary?

Did you read the thread? Brain has Konis. The perches on the Konis are lower than Bilstiens. So no. You can't.


Ok, last question.

What else do I need to make this WHOLE system work? I am going to get ISC or NB tophats, but aside from that, what bumpstops, spacers, etc. etc. do I need?

I highly recommend the 36mm FCM bumpstops.

Also, switching to NB style mounts will give you more travel, as well as more room to stuff a spring in while getting a lower ride height.

I'm pretty sure they compared NB Bilsteins to Brain's Konis. Not NA ones. Correct me if I'm wrong.