Ground Control Sleeves question
 

Will NB Bilstein ground control sleeves work on NA Bilsteins?

Need to know ASAP.

Thanks...

Probably, but be forewarned that the fit of the NA GC sleeves on my NA Bilsteins is pretty sketchy. GC supplies one "fits all" sleeve for the Miata (despite the fact that Konis, Billys & AGXs have different diameters and perches). The shock can literally bang around inside the sleeve and it seems that one big midwest pothole at speed could force the Billy right past the ill fitting GC sleeve perch.

I don't see why not. My spec had a coil over kit and it used the NA HD's. It had a ring on it to hold the sleve on it. Just make shure that the sleve is not loose and wont rock.

Have a great day,
Jared

hrm... well my plan is defeated anyways because the sleeves I found were mis-labeled as Bilstein sleeves when they were in fact Koni sleeves.

BUT... they are a great price, so do you think I could order the insert from GC for the NA Bilsteins? Has anyone done this before and if you have how much was it?

GC Sleeves on bilsteins are loose as fuck and rattle around the shock body.

So what do you suggest I do?

Should I get the Spec Miata sleeves from the guy here? IIRC they're about $150 shipped. I wanted them originally but this is a wicked good deal so it's hard to pass up.

Every little bit of $ helps with getting this car ready for the track

AFAIK, GC has one generic sleeve for all NAs (probably the same for NBs). They use a turned AL spacer (press fit insert) to suuport the perch on shocks (koni, AGX) that have a smaller diameter than Billys. Per my last conversation with GC on this, you knock out the AL ring and slip the sleeve over the Billy. Loose fit (which will make noise unless you wrap the shock body with some strips of rubber/inner tube) but it will "work". I'm either going to open up the AGX adapters that came with mine to fit the Billys or place the GC sleeves on top of the stock Billy AL perches (which really fit securely and well). Let me know if you want to see pics; I can pull the sleeves out and post some up.

I wouldn't mind pics actually...

How much height adjustment will I loose if I set the sleeve on top of the perch supplied by Bilstien for regular springs?

I'll try and get some pics up for you when I get home tonight. Not sure on the height adjustment loss; my Bilsteins are currently at SD getting re-valved but I may be able to do a guesstimate once I pull the Bilstein perches and GC sleeves out and eyeball them.

Falcon,

Pulled out the GC Sleeve setup and compared the AL insert ring to the Bilstein AL spring perch for use with standard Miata springs. Looks like mounting the GC sleeve directly on top of the Bilstein perch will be about 1" higher than using the GC sleeve directly on top of the Bilstein shock (albeit, with a loose and sloppy fit. Here's some pics:

1. Bilstein perch on left, GC sleeve in center (note recess in sleeve for press spacer), and AGX spacer ring on right.

2. Size comparison of AGX spacer ring to Bilstein perch. Bilstein is about 1/8 inch thicker, but AFAIK, "standard" GC application is to locate Bilstein shock ring at top of recess cut into GC sleeve (approx 1/2" up from bottom of sleeve). Thus, running GC sleeve on top of Bilstein perch will result in about spring being about 1" higher (1/2" recess in sleeve plus 1/2" thickness of Bilstein perch) than if mounting shock directly on/in sleeve. I'd still go for the bargain GC sleeves, you can always machine the AL insert rings if mounting the sleeves on top of the stock Bilstein perches does not let you lower the car enough (BTW, don't lower the car at all if you are using stock bumpstops).