tell me about...hubcentric adaptors

[dugong]

Hello.

How important is the width of the original wheel centre bore when fitting adaptors?

I know 5 x 114.3mm to 5 x 130mm adaptors exist, I know the cookie cutters are 71.6mm centre bore, my amazon wheels are approx 70mm centre bore (dude who's selling the wheels is getting back to me on the exact bore size).

Please clear this up because I want to see what these feckers look like .

[dugong]

Bump... help?

[dugong]

Right, the variables I'm worried about isn't so much the PCD but the centre bore size (on the original wheel itself) and the nut type used.

[slater]

if they use tapered nuts then of no importance what so ever.

[dugong]

slater said:

if they use tapered nuts then of no importance what so ever.

Sorry slater, could you clarify what you mean by this? The Volvo nuts are not tapered, not sure what the Porsche cookie cutters use.

What about the bore size of the hub? As the Volvo \ Porsche sizes are pretty close (70 mm Volvo, 71.6mm Porsche), do you reckon I'd get away with it? What's confusing me is all the adaptors I've seen listed go from one size (eg 67.2mm to the Porsche 71.6 mm). Should I just get the biggest \ closest bore size to 70 mm I can find, go with that and use tapered nuts, or have I completely misunderstood what you've said?

[dugong]

So far the biggest centre bore size I can find on a H&R supplier's website is 67.1mm to 71.6mm

Would this be enough?

[slater]

If your new wheels use taperd nuts then you can have a smaller spigot size on your adaptors as the taper will make sure the wheel goes on centeral.

tbh it could be a few mm out or so and not matter. i know some of my cars are/have been

[dugong]

slater said:

If your new wheels use taperd nuts then you can have a smaller spigot size on your adaptors as the taper will make sure the wheel goes on centeral.

tbh it could be a few mm out or so and not matter. I know some of my cars are/have been

Ooh that's rather interesting...

*PMs porsche wheel bloke*

[luckygti]

I've got hub centic adaptors to fit my ford alloys to my pug. Depends on the alloys and what spigot (a plastic ring in the centre bore) is fitted, if any. My understanding (such as it is!) is taht if the wheel isn't centred correctly then the wheel nuts may not be stong enough to hold the wheel central to the hub resulting in sheered bolts at worst and wobbly drive at best. Whether this would actually happen I don't know but i wanted to be safe and happy as opposed to wheel-less!!! Mine is for the track though and may be thrown around a bit more than yours??

[generally01]

Cookie cutters use tapered bolts.

[Robinxr4i]

The rims on my Sierra are Saab 9000 items the bore is bigger than the hub, they are bolt on using tapered nut. Which is fine.




*Just don't try bolting on non-matching bore wheels with wobbly bolts!

[v8lee]

I'm sure Rally Design used to do spigot adapter rings but I can't see any in the catalogue.
Might be worth a phone call.

[dugong]

generally01 said:

Cookie cutters use tapered bolts.

Excitings!

[gn3dr]

I would make sure you had the center bore adapter fitted - and at least one made from aluminium not plastic. That way the wheel is sitting on the hub in the centre and the bolts / nuts are just being used for clamping force to keep the wheel face clamped to the hub (as luckygti said)
If you do not use the centre bore adapter then the studs / boltsare being used for both shear and clamp force which they probably are not designed to do.

I know this from experience - although to be fair (to the sheared wheel studs) it happened when landing a rally car after getting some serious air over a jump......

[dugong]

Cheers for everyone's input on this.

I'll give Rally Design a ring tommorrow.... I want an aluminium adaptor for the central bore?

Bear in mind the Volvo wheel is 70mm or thereabouts, the Porsche wheel 71.6mm, the adaptor centre 67 ish.... is a few mm really going to matter with tapered nuts?

Not to sound shonky or anything but this is going to cost me a fair few quid anyway....

[luckygti]

The other option, and this is what I did to fit a set of Audi alloys to my VW was to get the centre bore machined out to fit! Although this will only matter if the centrebore is smaller!!!! Which it isn't!!!! Just ignore me i'm having a moment!

[playworker]

gn3dr said:

I would make sure you had the center bore adapter fitted - and at least one made from aluminium not plastic. That way the wheel is sitting on the hub in the centre and the bolts / nuts are just being used for clamping force to keep the wheel face clamped to the hub (as luckygti said)
If you do not use the centre bore adapter then the studs / boltsare being used for both shear and clamp force which they probably are not designed to do.

Although it's common to read this on modern car forums I'm surprised to read it on here - neither of my pre-80s cars have a centre bore, it's just the bolts alone which locate the wheel. IMO it's perfectly okay to do this as long as you have tapered wheel nuts/wheels and you take a little care to centre the wheel properly