HQ stud pattern, Commodore wheels

Each stud is off-centre only 0.33 mm, but the engineer had the proviso that the wheel MUST be located by the centre pilot, so there is no side force to break the studs. This is usually not the case, most alloy wheels on these cars are not centrally located.

Dr Terry

Ok, though he knew the Centerlines I have lined up for it. I'll check it all, and if in doubt, get some new axles...

But the whole point is that no matter how you locate it there will be lateral force on the studs, which they are not designed for. With mag nuts I can see the possibility of loose tolerances but with tapered nuts and seats the studs will hate you.

An axle that has been re-drilled may not be perfectly accurate (factory ones may not be great either) but I would certainly expect it to be a lot closer than that.

With the history of hq/Commy mix and match disasters, I think it's time to dob in that engineer.

Each stud is off-centre only 0.33 mm, but the engineer had the proviso that the wheel MUST be located by the centre pilot, so there is no side force to break the studs. This is usually not the case, most alloy wheels on these cars are not centrally located.

 

Dr Terry

Shit, you're right. My alloys have the plastic cup that fits inside the centre hole.... technically allowing the rim to side load the studs. Also, getting back to factory 'tolerances' reguarding stud location, would explain why sometimes the nuts don't want to go in the stud holes sometimes... a little jiggle of the rim gets things moving though.

I'm in the process of swapping my banjo for the BW78. The front discs are starting to cry enough after 27 years of my ownership so I'll be upgrading everything to Commodore. Better keep the verniers out where I can see them!

Old thread, and interesting topic, but I was just told by an engineer that using HQ pattern wheels on Commo stud pattern is fine by him. As long as the center fits the wheel ok, he reasons it is an ok thing to do, and offered that each stud being out by just 0.5mm according to his calculations isn't enough to make a dangerous difference. He also said most axles that are re-holed would vary by that much anyway, and that original HQ-spec axles back in the day could have those variances. 

 

This has confused the hell out of me given the above info. Not something I want to get wrong, but if a VSMMC-certified engineer is ok with it....

Well I have a set of dragway mags that run the shank wheel nut, without locating on the centre bore there is no way in hell i can get more than two wheel nuts on without forcing the studs out of place on a VN diff...

hi looking at using hq gts rims on my car that commodore axle, can i machine down OD on these to use on my rims??

http://www.ebay.com....=item2ec2369d25

NO. 

Stud pattern is still to far off.

Get HQ axles or run commy rims.

Cheers.

NO. 

 

Stud pattern is still to far off.

 

Get HQ axles or run commy rims.

 

Cheers.

it bolted up fine, i know there a slite diff in it,  just center hub was about 2mm small

Yes it will bolt up "fine"

But its not fine.

If you feel like running the risk of loosing a wheel, go ahead. Its due to dodgy modifications like your considering that car enthusiasts have such a bad name and that we have such strict rules we have to abide by.

I've been thinking about this subject for the last few days. My original plan was to run VB - VK drums on the redrilled Torana axles I bought off eBay., but it struck me the other day that the centre hole will be a different size.

Is it feasible for me to convert to HQ rear drums and carefully file the holes, maintaining a tight fit or will I be better to either increase the diameter of the centre spigot or have the Torana or possibly HQ drums redrilled ?

Thanks for your help.

Yes it will bolt up "fine"

But its not fine.

If you feel like running the risk of loosing a wheel, go ahead. Its due to dodgy modifications like your considering that car enthusiasts have such a bad name and that we have such strict rules we have to abide by.

Edited by snickersbar, 07 December 2013 - 06:34 AM.

The nuts and seats are tapered so when you tighten them they will stress the studs.

Yep, if your running tapered nuts and wheels it will stress the thread sideways, if you run the shank type wheel nuts you simply wont get them on.

From memory its about .4 of a mm out, way, way to much for my liking.

There is talk about machine shops and the like not getting redrilled ones any closer than that, i'd tend to disagree.

I'd be pretty upset if i got further than that out using a cordless and a tape measure, so surely with a lathe a mill and an indexing hub handy they can get them closer....

Cheers.

Yep, if your running tapered nuts and wheels it will stress the thread sideways, if you run the shank type wheel nuts you simply wont get them on.
 
From memory its about .4 of a mm out, way, way to much for my liking.
 
There is talk about machine shops and the like not getting redrilled ones any closer than that, i'd tend to disagree.
 
I'd be pretty upset if i got further than that out using a cordless and a tape measure, so surely with a lathe a mill and an indexing hub handy they can get them closer....
 
Cheers.

Your life. 

Personally i wouldnt go any faster than about 20kph with them.

Cheers.

Your life. 
 
Personally i wouldnt go any faster than about 20kph with them.
 
Cheers.

Try Dragway or Intro?

Do you now a good place to get old school looking rims for commodore??

Com back hz front same with the wheel nuts   

HQ hub diameter is 71.5mm, Pre VE* Commodore is 69.5mm.

HQ uses 7/16" UNF studs, Pre VE Commodore use 12mm studs

As there is only 0.026" difference in the PCD, how did you measure it? With an inch ruler?







* Except 4 cyl VC/VH which uses 63.5mm

7/16 inch equals 11.1125 mm, feasible to get 12mm Commodore studs put into HQ pattern gear with an offset hole drilled to the correct PCD??? Although for a set of HQ front discs, probably simpler to start with blanks!

Edited by cruisindoug, 03 July 2014 - 06:18 PM.

I've been wondering exactly the same thing. I've got a couple of near new discs from a HZ. Was going to ring the machine shop who drilled my brake drums after I got the exact measurements.

Edited by Lazarus, 03 July 2014 - 10:01 PM.