deezums

iTrader: (3)

Hello again!

I've got a set of DIY billies for sale, new B8 Billies (purchased Feb 2017) 7" Summit coils, 350lb front, 250lb rear. 1" front/1.5" rear drop hats, made custom from NB top hats (cut out top hat using something, like my hole saw tool, find 2.5" OD tube, slip in, weld, win) includes upper spring locators and factory style shaft isolation and lower bushings. A neat little hole saw pilot tool to bore out NB shock towers to 2.5" diameter, bolt up a empty NB top hat, slip the pilot in and drill away.

I built a rudimentary shock dyno and plotted all four of these shocks. My old NA6 ran NB HDs and much higher spring rates, was always trash but I didn't know it then. I am unconvinced you can ever run a spring much stiffer than this on any Bilsteins without them becoming out of control messes, unless you drive 100% on glass or something. They'll be drastically oversprung and concrete expansion joints or perfectly spaced potholes will be your worst enemy, ever.

That was my reasoning behind picking these much softer rates so these ride amazing for a DD on everyday roads but they aren't super stiff, good 200tw tires and smooth pavement and you will find the bumpstops in short order. Swaybars may help, I kept the front sport NB bar the entire time I ran these. This was my eventual reason for upgrading to xidas, HPDEs, which is why these are now for sale.

Looking for $500 shipped. .csv files from the "dyno" are available if you want them.

Here's a link that might explain the dyno a little more, it's been a while...
Megasquirt Support Forum (MSEXTRA) ? Help with Formulas, calculated fields... (View topic)

Willem Spencer

Hey, I am interested in your Bilsteins.

I have an na6 and I’m wondering how well this setup would work on my car.

Did you purchase the shocks new? Do you have the serial numbers?

deezums

iTrader: (3)

Yep, they were brand new from TireRack.

I don't have the serial numbers, although you can kind of make one out. Looking at the photos it seems the rear sleeves obscure the rear shock info. With the drop hats the spring is never loose, so I have to take them apart to read them. Not really looking to do that.

These should work fine on a NA and won't require shock tower cutting.

Dwalk51

Also PM’d

JDubya

How would they work on NA6 for DD and autocross?
The 1.5" tophats would help, but if set to a ride height of around 12.5 to 13 inches, would the longer body NB Bilsteins be hitting the bump stops? I'm not quite sure how to ascertain travel and ride height. Or would stiffer springs be recommended for that ride height? What ride height would you recommend for atocross and DD with this setup?

deezums

iTrader: (3)

They are set for about 12.5" under NB2 weights, would be pretty similar on a NA. From where it is to +1.5" or so would be fine.

And these are pretty much short bodied shocks with the extended top hats. I moved the upper shock mounting location up. The shocks might be long, but my holes are deeper. You wouldn't want to do this if you want OEM ride height, you would be wasting shock compression travel you'd never use, stealing it from rebound travel a shorter perch to perch height (higher ride height, same spring) might actually be able to use. It's all in the spring rate and how far the car statically compresses that, then centering shock travel around that and tire/control arm clearances by moving the upper perch higher. Since you still can't compress even these pansy springs much under static weight of a miata I also added more clearance towards the compression side so I could run bigger bumpstops on shock travel I never use. Rubber is a progressive spring, so using a longer soft one means the shock sees less peak force at the high velocities it's weak at. In other words, it won't pogo off the very hard tiny bumpstops like most bilstein setups.

They will body roll pretty aggressively on 200TW tires, maybe less if you upgrade the swaybar. It's still capable of being fast since it's smooth as it rolls into and out of the stops like an OEM miata, twice as stiff and a lot lower? If you like hard and fast turn in, this isn't really much good at that. Setting the car for a corner takes more time, just how it is on soft springs.

deezums

iTrader: (3)

SOLD!

Thanks guys!