andym

700 spring rates on nb bilsteins would likely need a revalve to be useful.

Bronson M

iTrader: (1)

I won an auto x regional championship on 800/450 mounted on stock hard S Bilsteins. So "useful" is a relative term, are they better with a revalve? Absolutely, but personally I think they work quite well, they have more low speed rebound than HD's that the spec guys run. Only really ever noticed them lacking on very rough pavement.

SeanBonham

Got my NA HD Bilsteins all put together. 450 / 300 springs. Wonder what a good sway bar match would be? The FM front bar is the cheapest, the tubular RB bar is also well loved it seems although quite a bit more expensive. Yall have any suggestions? Mostly street car, a few autocross here and there. Keeping stock rear bar I believe.

concealer404

iTrader: (3)

Spring rates first, shocks second. It'll work fine in terms of performance. Will ride like ***. Better shocks would generally feel better. The car should be faster on 700/400 than 350/275 in your case though. I also agree, 350/275 is too soft. My default suggestion is 550/350-375. I've run as high as 600/400 on stock shocks and they were fine. Would not hesitate to go higher if track work became more important than low speed street manners.

imperialgolem

I definately agree
i have 400/325 revalved. I do not know how guys uses even those rates or higher on stock bilies.
Wheel control is far away... without more damping.
For me it is driving on Springs instead of using shocks if it has no damping.
In mx5 according to critical damping rear are to high compare to front, it is not easy to feel it on car, but i can confirm that it works. ( i made plenty of tests).
Coming back to topic front and rear are to low for rates which you have mentioned

sixshooter

iTrader: (12)

I've got 550/350 on MSM fronts and Hard S rears and had Hard S all the way around before I blew one. It's a little busy on rough roads but not a bad ride at all. 400/275 was plush on the Hard S. I'm using larger sways front and rear and my rear should be running a smaller bar than it is with these rates. It's a balancing act and mine's a little off. But it's getting ready to change a little.

imperialgolem

You confirmed exactly what i felt during investigation.
It is underdamped shake feeling - high frequency and low amplitude. Car does not behave flat at all.

emilio700

iTrader: (3)

What the heck does this even mean?

imperialgolem

It means - setup lacks damping in some areas. Shake can occur if body is overdamped or underdamped.

diverdale

I just priced out new billis and it seems that building coilovers using new shocks is gonna be about the same cost as some shall not be named already built ones. Am I wrong?

andym

Depends on what your build / parts list entails and what the shall not be named option includes.
NB shocks are where it is at. Not all shall not be named options use nb shocks.
Extended top hats on front and rear and a nice upgrade.

Headcase0

Thank you all for the replies, though after some more research, I've settled on getting some Tein Flex-Zs for my next suspension upgrade and pawn these off to a friend who would like a softer setup like mine. If anyone is interested, the reason behind choosing the Flex Zs are their valving takes well to higher rate springs (I'll essentially be on 500/335), come with pillow ball top hats, have rebound/compression adjustment (even if it's only the one dial), and I can use a stepper motor kit for fancy computer controlled adjustable damping. Side note: What do you guys feel would be a fair price for 60k mile Hard Ss with ground control sleeves, eibach 350/275 springs, FM bumpstops, and NB top hats?

concealer404

iTrader: (3)

ALL new parts with minimal shopping for deals, you can expect to spend in the $800-$1000 range.

They will be the best $1000 and under coilovers you can buy/build. <---- If you disagree with this statement, then buy whatever you feel is better.

emilio700

iTrader: (3)

I would choose a DIY Bilstein setup over any Tein coilover. Hasn't always been the case but since Tein decided to battle the generic Chinese ebay coilovers about 5 years ago, they have gone south in terms of production quality, features and specs.

Junkwhale

Agree with Billies over Tein.

DIY 600/350 setup on MSM bilsteins felt better than the 450/335 Tein coilovers (8Kg/mm / 6Kg/mm) that came on a car I bought.

sbirk

So I just got my suspension built out with the following parts

-MSM Billies with only 40k miles
- ISC Top hats front/rear
- 550/350 QA1 springs
- Integra bumpstops
- spring washer
- coil spring isolator
- Advanced autosports sleeves

So a few things about the assembly. I didn't realize I needed to grind out the front mounting holes to fit the ISC top hats, so that took a while. the assembly all in all went well, I used gorilla glue to attach the spring isolator to the top hats. I have it set to almost the bottom of the sleeves (only 3 threads visible after the perch) and it sits at a great ride height. It rides with almost no body roll and cornering has been greatly improved. My only issues are that the springs seem to rub against the sleeves as the paint is coming off the sleeves and on bumpy roads it starts sounding really bad. And at high speeds submoderate roads feel super bumpy and when going above 70mph there is much more cowl shake. Is this due to my spring rates? Are my shocks bad? Maybe I need helper springs? Maybe I didn't glue the isolators well enough? I really feel it shouldn't be this bumpy. I also have frame rails and FM sway bars, I have fender braces from garagestar I'm going to install soon and I will be getting door bars and a roll bar from hard dog soon.

bahurd

iTrader: (8)

Do you have the lower perches turned the right way? IIRC, they have one side with a sort of “hub” that centralizes the spring and keeps it off the sleeve.

sbirk

I wasn't aware it had that. These perches are flat across the top. They are held in place with a little allen key bolt that screws into the threads. Here's the link for what it looks like https://www.advanced-autosports.com/...sleeve-and-nut

Thank you for your help!!

concealer404

iTrader: (3)

Have you cut your bumpstops to an appropriate length?

sbirk

Yes, I cut them to about halfway up the third bump on them, and then I used the remainder on top of the top hat