I'll be using this thread to post information about a set of 17" XXR 962 wheels I've purchased for my '86 XJ-S. The wheels are actually already in my garage and are awaiting a couple necessary modifications.

The first necessary step is to get the center bores enlarged at a machine shop from 73.1mm to the correct size for the XJ-S.

I've been frustrated by the lack of consistency in the citing of the Jaguar center bore online, and have seen it cited as:

• 73.8mm
• 73.85mm
• 73.9mm
• 74.1mm

My car is in the shop now and I had the mechanic remove a wheel and measure the hub with a digital caliper. He came up with 73.85mm. Acording to a poster on jag-lovers, he measured his hub as 2.907", which comes out to 73.8378mm, very close to my mechanic's measurement.

That said, though some have measured the hub diamter, what I HAVEN'T seen anyone measure is the actual center bore of the wheel to see if it's possible that Jaguar may have overbored the wheel to accomodate an inability to machine every wheel to 73.85mm exactly. I think it's very possible that the Jaguar wheels are only approximately hub-centered, the hubs being 73.85 and the wheel being closer to 74.1.

So even though the measurement is usually given as "hub diamter/center bore," with the XJS (and possibly other Jags) we may find that these two are in fact two different measurments ,1-2mm apart, and so must be separately labeled.

Coventry Wheels lists the center bore as 73.9mm. I think that is an ideal target for the center bore of an aftermarket wheel to be enlarged to, assuming the machine shop can hit the number that precisely. If the shop can't hit the number that exactly, it may be better to give them 74.0mm as the target and allow for a 1mm variance in either direction, so that the actual center bore could be no less than 73.9 and no more than 74.1mm.

Seth

 

What's an XXR 962 wheel?





Not that you asked but when I went thru this (ages ago) I just took one of my OEM Jaguar wheels to the machinist as a sample for measurement and he bored my new wheels to the same size. <shrug>


Cheers
DD

 

It's an aftermarket wheel see here XXR 962

You will also need to have the PCD altered to 5X120.65, I assume the XXR will be 5X120 with metric stud holes. This is quite easy as the Jag has larger wheel studs and holes in the wheel.

cheers
Warren

 

That link Warren posted is the wheel. It already comes in the 5 X 120.65 PCD, so no bolt circle alterations are needed. I ordered four 17" X 9" wheels. The offset on the rear is almost perfect as is. The front two wheels will be narrowed to 8" by Weldcraft in Michigan, and after being narrowed by 1" the offset becomes perfect in front as well.

So Step 1—enlarge the bore ever-so-slightly. Step 2—get the fronts narrowed to 8".

Doug, if my suspicion is correct, and the Jaguar wheels are over-bored to 74.1 as compared to an actual hub diameter of around 73.85, I don't want to replicate the same amount of slop that Jaguar may have built in when I could have it machined to be a true hub-centric fit at a tighter 73.9 or so. That's why I'm more concerned with the actual hub diameter rather than the wheel bore. Hope that makes sense. Of course, I guess if the wheel bore is 73.85, that would help settle things...I may have to dig my spare out...