1/2 inch wheel studs

[maxwedge5281]

i recently changed my wheels from minilite look spline drive to real minilite bolt ons on my v8 powered bj7. i have changed over to the longest arp 7/16 by 20 thread wheel studs. these are approximately 2 7/8 inches long below the head of the stud. with the standard minilite offset on 6 by 15 wheels i had to reduce my rear tire size from a 225/60/15 to a 195/60/15. if i could use a wheel stud one half inch longer i could put in a quarter inch spacer and add a couple of tire sizes on the rear. have any of you racers upgraded to 1/2 inch wheel studs? thanks for any help or advice. .

 

[Barryp]

Hi Maxwedge,
I considered going down this road too, but most racers that I've spoke with are using the 7/16" studs, either case 3" seems to be the longest stud any of the well known manufactures market. Also going to 1/2" wouldn't leave a lot of meat on the rear hubs after enlarging the holes. I spoke to several companies that can make custom rolled thread studs in the length I was wanting but man it is pricey, the best quote I got was 18.00 per unit min qty of 100. ARP can do them too, but there is a $500.00 set up fee for anything "custom" on top of a pretty high unit price. So instead of a 1" spacer and maximum track width at the rear I've resolved to a 1/2" spacers and 1" total less track on the rear.



Barry

 

[HealeyRick]

Depending how desperate you are for that extra tire width you could swap out the rear axle. I believe some 80s Chevy Vans have a 5 on 5 bolt pattern that matches the Healey wheels. Van axle should be cheap at the junkyard, get it narrowed to your preferred width, weld on some mounts and you're ready for some smoky burnouts with a stronger rear axle thrown in.

 

[Randy Forbes]

Larry, there are alternative spacers, but you might have to revert back to the wire-wheel brake drums to use them. I'm not sure what minimum thickness this pattern is available, but these suited my needs at the time...

 

[maxwedge5281]

thanks guys for the input. i need a longer stud to move the tire and wheel away from the body in order to run a larger tire on the six inch rear wheels. a 1/4 inch spacer would help with that but leave too few threads for the wheel nuts to properly secure the wheels. after mounting the fronts with the regular wheel studs i was not pleased with the number of threads available for the wheel nuts. i took the factory rear wheel studs and moved them to the front hubs and had plenty of threads. and, yes the 1/2 inch wheel studs have a much larger knurl and i could not find any of those much longer than the arps that i am using. overall very pleased with the minilite boltons! just wish i could run a 225/60 on the rear.....oh welll since this is a v8 conversion, i am planning to replace the rear axle with a 8.8 ford rear with disc brakes. i will have to have it cut to fit the car and i will have the overall track width built to accomodate wider tires....but not extended beyond the rear fender opening!

 

[maxwedge5281]

randy thank you for the picture..that might work on my car. is that a custom spacer of you design or did you buy aftermarket? were you using the factory road wheels or an aftermarket wheel?

 

[red57]

Entering this thread a bit late but here is the solution I chose when I converted to bolt-on wheels. I used grade 8 bolts - it's been about 17 years since I did the conversion so don't remember the length I used. I just put the bolts thru the bearing carrier and axle flange and the spacers and bolted them up tight so they were straight & true then tack welded the heads to the bearing carrier so they can't turn or move and then reassemble with bearings and good to go. I used wire wheel drums (disc wheel drums are way too heavy) and 1" spacers for a long time before eventually converting to rear discs. Some engineers might questions this solution but as I said I did it many years ago and have around 90 race events and a lot of street miles since with no problems at all.
I agree that there isn't enough meat to open the axle & bearing carriers to 1/2". And, if you are thinking of racing, most organizations will not allow spacers like Randy is showing - the wheel stud needs to go thru both the wheel and axle.

 

[Randy Forbes]

Those spacers were an off the shelf item, nothing special. I think they go to that pattern when you exceed a certain thickness, or of course, if you're changing from one diameter of bolt-circle to another (mine were straight 5 on 5 to 5 on 5).

I didn't really have any clearance issues, but the rear track without them was >2" narrower than the front. It was when someone following me later said that they could see half of my front tires__on either side__that I decided to spread them out a little (1" or 1-1/4"__don't remember now__each side).

I was using Chevrolet style Ralle Wheels, 15 x 6 with 195/65 tires.

Red57: I understand that rules are rules (and that's just the way it is, if you want to play in their sanbox ) but it would seem from an engineering standpoint, that the albeit heavier and with more unsprung weight, bolt-on spacers would be more secure than ones using the extended lug studs/bolts. I do see a point of contention being maintenance related; how do you (or an event tech inspector) know if what you can't see is still torqued down to spec?

I've since reverted back to wire wheels and splined hubs, and Larry's plan is to fit a tailored axle, so I guess we won't have to worry about breaking the rules

 

[HealeyRick]

Oh Boy. Might as well spring for traction-lok, too. Should work great and I think Moser and Currie can drill your lug pattern to anything you want.