So in my irresponsible endeavor to fix or upgrade everything on my Xk8 and spend more money than it's worth, I'm looking at the suspension.

It has stock springs. 116k miles currently

This is what I know has been done to it based on records, but more may have been done I'm not aware of (i.e. the shock mounts up front seem new - see photos)

86k miles - Stabilizer Bar Bushings
111k miles - Rear shock absorbers
As you can see the mounts up front are new, but no idea when that was done as it isn't documented.

My suspension measured from the center of the wheel to the bottom of the wheel arches is:

Front: 14.5"
Rear: 15"

Based on what I've read that seems low, and everything points to that being the strut mounts up front, but again, they look pretty new (if off centered a bit).

I can't afford the Nitron Coilovers ($3995).

I've looked at BR Racing and Cieka coilovers ($1200 ish)

I haven't found a lot of people who have used either on an XK8 but I've seen both brands used on other cars and the results are positive.

Cost-efficient is:
Lowering springs
New struts up front (Bilstein)

New strut mounts (Wayne)

or should I go with the coilovers? It's a handful of hundreds difference by the time I add in the struts and mounts, etc, but haven't seen a ton of info on anyone running the cheaper non-Nitron versions)

I did just find this seller too - which is a complete kit: https://www.ebay.com/itm/22442784675...Bk9SR4KJuoToZA

 

Over in the xk150 forum there are individuals who have installed the BC Racing coil overs

On that car you have many options to get exactly what you want from BCR.

The ride height is adjustable from stock to lower and lower on the xk150.

All reports I’ve read are positive. Pricing 1200~1500 typically (maybe a Black Friday Sale somewhere).

With the BCR Wayne will be out a sale since you won’t need the mounts.


an aside...is the rear exhaust (shown) a mandrel bent (round) hoop over the rear axle?

wj

 

Yes, it's the Adamesh Stage 2 over axle, combined with the Adamesh Stage 1.

 

I just lowered mine with the adamesh springs, seems to work well. Your car looks very clean, no crusty rust on the rear subframe mounts. Are they new? I did look at just replacing the shocks with aftermarket coilovers I just wasn't convinced on the ride comfort but it will likely be fine.

 

You can use the new Swallow Racing coilover kit they released for the X100!

 

I was looking at those. Most coilovers don't use a top mount. The Swallows does. According to Swallows "Brand new front top mounts are used and on the rears OE mounts from SNG Barrett are used (Made to original spec). Polyurethane mounts were not used here as we felt it compromised the drivability by making an already stiff damper stiffer and made the noise translation increase through the damper body."

It seems that by using new top mounts which seem to all need to be replaced fairly frequently (unless using the ones by Wayne or Steve) it doesn't solve the problem of having to replace top mounts - and they say that the poly ones would make it extremely stiff (stiff on top of stiff).

 

If you go the Ceika route, do some searching on here for the member that converted the rear to a true coilover. It likely applies to other brands without true rears.

BC offers a coilover for the X150, I have not seen anything for the X100.

 

The X100 suspension is already coilover front and back.

 

I'm looking at the kit offered by Swallows which looks to be a pretty good package.

 

A "coilover" is a single unit that combines both a coil spring and a shock absorber. X100 does not have a single unit from the factory on the rear, the lower shock/spring do not share the same mounting location.