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Discussion Starter #1
Hey, seems like everyone I talk to has a different opinion about the wheel stud lengths and type of lug nuts I should run on my 69 coupe with 17" Riddler mags.

So do I go with the original studs for the front and rear or do I need longer studs?

Also what type of lug nuts do I need?

This seems like a silly question but honestly the last three shops I have been to have either mentioned my lugs or my studs and they all have different opinions it seems.


Thanks in advance!!!

Randy
 

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Go with the lug nut style recommended by the wheel manufacturer.

Your studs should be long enough to get about 3/4” or more thread depth. If you use open lugs the studs should protrude a few threads out past the nut. If closed lug you want the same thread depth but need to make sure studs are not too long and bottoming out before tight.

If your existing stud are too short you can change them or use extended thread lug nuts.
 

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Long wheel studs are required by the NHRA which is why all race cars have them.

Your street driven car needs a wheel stud that is long enough to pass through the nut (unless it is an acorn style for appearances). The threads have to stick out half of the tickness of the stud to hold the nut in place (this is true of every nut used on a threaded stud). So a half inch wheel stud requires a quarter of an inch sticking out above the lug nut to provide maximum clamping force.

The face of the lug nut has to match the wheel. Aftermarket wheels generally use a flat nut with a flat washer under it to prevent galling the aluminum face of the wheel. Steel wheels use a forty five degree conical face to center the lug nut on the wheel to draw it up true to the central hub. Never use a stock steel wheel lug nut with an aluminum aftermarket wheel, even when reversed to have the cone pointing out.

Note all steel wheels are held on by lug nuts, but the weight rides on the machined central wheel hub. It is a tight fit which is why the wheel has to be rocked or kicked to get it off the central wheel hub. Aftermarket wheel have all of the car's weight riding on the wheel studs: which isn't how he car was designed to operate. This is why a lot of wheel studs break with use of aftermarket wheels.

Why do aftermarket wheels have such large holes (both lug nut holes and central wheel hub hole) where a tight fit over the central wheel hub is required? Because they can make more money by having a universal fit wheel; that doesn't fit anything. With one wheel fitting many car models, years, and stud sizes according to their catalog they save money on inventory.

Big Dave
 

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Correct Dave but not all aluminum wheels use flat washers. In fact most of the popular wheel I see do not.

For example the America Racing TT use a 60* conical.

That’s why I would consult the manufacturer as to lug nut style.

On summits website Ridler wheels also take 60* conical. May or may not be correct for the actual wheel the OP has
 

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As an engineer I find that idea (conical lug nuts) with an aluminum wheel as a source of problems. Aluminum is soft so it will gall with steel rubbing it under pressure. This can generate stress risers in the aluminum. Second issue is aluminum work hardens very readily. It can become very brittle and fail at the stud hole if the wheels are removed frequently. Unless the wheel manufactures has a steel insert under the lug (or a conical washer) I would hold these wheels to be suspect.

I use fifteen inch steel wheels because I like the idea of a sleeper, and hate narrow side walls with my tight suspension and stiff springs. They are also strong and resilient making them great for road racing as well as straight line driving.

I not only use steel wheels, but I source HD Chevy wheels off of cop cars as hey are fully vented and clear 12 inch brake rotors. I can widen or narrow the wheel to taste as there are two wheelwrights in town that cater to the roundy-round racers that are prevalent in the south east.

Big Dave
 

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Discussion Starter #6
wow, great guidance here guys.


Randy
 

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Dave. I get what you’re saying on conical lugs and aluminum wheels. I may be wrong but I believe almost every new car today that comes with factory aluminum wheel use conical lug nut as opposed to flat washers.

I also see that most aftermarket companies also use conical.

If the wheels are torqued correctly to 100 ft lbs in proper sequence I see no issues.

Bottom line. The required nut design is 100% based on what the manufacturer designed the wheel to use. Can’t put a flat washer on a wheel that is not designed to accept it and visa versa
 

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Could be right John. I have never had my aluminum 20" Silverado wheels off of the truck. I will have to replace my tires soon, even though I have only 11,200 miles on the truck. because they are seven years old now (and my truck is parked outside in the Florida sun).

Big Dave
 

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Mind in the Vegas sun. 55k miles on them.

Will be completing my move to Tampa in the fall.
 
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