Change 1/2" studs to 14mm

[luvbowties]

I'm running 88-92 Super Sport Chevy chrome rims, shown below, and having problems with hitting potholes(un-missable)and knocking wheels out of round at their mounting lugs. I'm torqueing them to 100 ft-lbs.

Has anyone changed the 1971 front rotor-studs and rear axle-studs from the 1/2" to 14mm as used on the 88-92(and later) pickups? I haven't measured the conical portions of the 2 nuts, but I'm guessing I will find the 14mm to have a larger starting diameter with the same degree taper--giving a fuller/meatier fastening inside the wheel holes.

Any other ideas are appreciated.
Thanks,
Sam

[Tazimafied]

You need these:

http://www.ezaccessory.com/GM_1_2_Ex...djqyrosseccaze

This was the first link I could find so you may be able to find them cheaper somewhere else.

I used these on my '76 blazer so I could use later model center caps.







The taper is designed for newer wheels like yours but I am using basic steelies so I had to have the taper turned down to fit at a local machine shop.

[luvbowties]

I was really interested in some way to keep wheels centered and rolling true--hence the question about if bigger studs(and higher 'effective' torque)might help. Thanks,
Sam

[slepysal]

Originally Posted by luvbowties

I was really interested in some way to keep wheels centered and rolling true--hence the question about if bigger studs(and higher 'effective' torque)might help. Thanks,
Sam

Sam have you thought of using an "ET" style lug nut ?
https://www.summitracing.com/parts/c...FdgOgQoddeQOCw

[andyh1956]

This is what you need. Later wheels are hub piloted where as the older wheels were stud piloted.
https://www.uswheeladapters.com/hub-...FZGJaQodgXEIIA

[jayoldschool]

Running an aluminum wheel nut ("bulge" seat) instead of a steel wheel nut will give you larger surface area contact on the cone.

Steel wheel:



Aluminum wheel/bulge seat:

[Tazimafied]

Originally Posted by luvbowties

I was really interested in some way to keep wheels centered and rolling true--hence the question about if bigger studs(and higher 'effective' torque)might help. Thanks,
Sam

The 1/2 inch studs are more than strong enough to hold the wheel in place unless you are throwing down over 500 HP or have tires over 35 inches in diameter. For more piece of mind you can use the adaptor rings Andy mentioned but it isn't absolutely necessary unless you are using the non tapered "mag" style lugs. The ET lugs mentioned wont work with the center cps you have and the stock lugs have the same size taper as the aluminum wheel lugs also mentioned. Just make sure you have the proper amount of torque applied.

[luvbowties]

Thanks to all for your ideas and suggestions.
Sam

[Tazimafied]

Post a pic when you get them mounted.

[luvbowties]

Originally Posted by Tazimafied

Post a pic when you get them mounted.

Hope this pic shows them well enough. Thx for interest.
Sam

[slepysal]

They look great ! So what lug nuts did you use to mount them ?

[Tazimafied]

And what center caps are those? Very nice!

[luvbowties]

Originally Posted by slepysal

They look great ! So what lug nuts did you use to mount them ?

Used the standard, older 1/2-20 dual threaded nuts like came on ??-YEAR 1/2 ton Chevy pickups/vans--studs are std. on the 1971 rotors I used. These std. nuts and studs are what I believe are allowing the wheels to be knocked off center when I hit the terrible pot holes around here. Thinking the 14mm studs and nuts may hold them from 'bouncing' off-center. Not much diff. in 1/2" and 14mm; but that tiny bit may be the cause. And would be an easy fix.

"Quote:And what center caps are those? Very nice!"
Not sure. Bo't 'em off Ebay for like $40, new in wrappers with new black attachment caps. Came on some kind of pickup , or more likely some kind of van. Think the higher torque I've applied may hold 'em. If so, I'll put black-and-red bow-tie center decals to tie the caps into color of truck:see closeup pics of just wheels-and-caps on #1......thx for compliments; really did not expect them!

Was interesting to see torque specs I found on both studs--alignment guys tell me they just apply 100 ft-lbs w/o looking up specs on both sizes. When complaints come in, they up the 14mm to 110 ft-lbs. Surely wow'ed me!

Sam

[Tazimafied]

100 ft-lbs is what I use on my Blazer and it has been working well even with the 33's. If your wheels are getting knocked off center at that torque I would think that the taper of the nut isn't making it far enough in to the wheel. I would recheck to see if you might need to have the taper turned down a bit like I did.

[BigDan3131]

75 max on aluminum and 100 on steel is the rule the mechanic I use to work with said.

[luvbowties]

Originally Posted by Tazimafied

100 ft-lbs is what I use on my Blazer and it has been working well even with the 33's. If your wheels are getting knocked off center at that torque I would think that the taper of the nut isn't making it far enough in to the wheel. I would recheck to see if you might need to have the taper turned down a bit like I did.

Your thinking gels with my 1st theory--see #1. Did u taper your lugs toward a closer imaginary point or a farther away point? How were they done, like on a lathe with lugs tightened onto a partly- threaded stud?

Another question, since I could do this myself: do you think drilling the wheel holes just a tad bigger would give the desired result?

Thanks for your thoughts/ideas.
Sam

[Tazimafied]

I wouldn't do anything to the wheels only because removing material there is a big unknown. The stamping has a specific shape that I wouldn't want to mess with.

The easiest way to see if the taper of the lug fits your wheel is to take one off and see where the lug sits in the wheel. The nut should sit about half way in to the wheel. If it looks like it is sitting on top of the wheel or just barely inside then you should turn the taper down.

I had mine done at a local machine shop so I'm not sure how it was done. They were cut at the same angle and enough material was removed to get rid of the flat spot at the end of the taper.