NHRA wheel stud rule ? A litle confusing

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hotrodhoodlum

X Nostalgia Drag Racer
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What is your thinking on this ?? Do any of you racers not have your studs sticking past your lug nuts and pass tech . I have 3" studs all ready on the rear and they do not sick out past the lugs I am running Weld wheels and they are very thick

The way I read the rule for wheel studs is that the lug nut must protrude the wheel studs by at least the diameter of the stud not go past the lug so it sticks out just in the lug nut the diameter . So if you have a 1/2" wheel stud and the the shank of the stud is 1 1/2 " long and its an open lug it is all ways going to be at at least 1/2" into the lug nut even though the stud does not stick out past the open lug.
 
"The thread engagement on all wheel studs to the lug nut, or lug bolts to wheel hubs, must be equivalent to or greater than the diameter of the stud/bolt. Length of the stud/bolt does not determine permissibility. (Example: A 7/16-inch stud must be thoroughly engaged through the threads in the hex portion of the lug a minimum of 7/16-inch.)"

The way I interpret that and the way that the rule book graphic shows is that your stud must protrude at least the diameter of the stud itself. So if you have a 1/2" stud, you'll need 1/2" of it sticking out past your wheel surface. Just as you said.
 
The lugnuts on my Dart are flush with the the end of the 3" studs. As long as there is 1/2" of threads on the head of the lugnut (clamping part) holding your wheel on you should be fine. I had my wilwood rotor hats machined .100" on the face that the wheel rests because of this issue. I have not had a problem with tech with this setup
 
When you remove a lugnut you should see at least 1/2" of lug sticking out past the Weld wheel. You can't include the shank portion of the lugnut in the calculation. You should really have 3/4" to account for the thick washer under the lugnut.
 
I dont know if mine will pass, but I cut the tops off of my lug nuts because there were no threads and screwed them on all the way like normal, so now the studs go all the way through my lug nuts. This is fine, right?
 
The thread engagement on all wheel studs to the lug nut, or lug bolts to
wheel hubs, must be equivalent to or greater than the diameter of
the stud/bolt. Length of the stud/bolt does not determine
permissibility. (Example: A 7/16-inch stud must be thoroughly
engaged through the threads in the hex portion of the lug a
minimum of 7/16-inch.)

from 2012 Nhra rule book...

the stud does not need to go thru the open end of the lug nut....must engage the hex part of the head of the lug by at least the diameter of the stud...as noted in the example....my 71 demon with strange brakes and 3 inch studs do not go thru the end of the lug nut...passed tech in Vegas, Fallon and now Sacramento.
 
Great that is what I thought because I am all ready running 3" studs

Thank You for reassuring me

The lugnuts on my Dart are flush with the the end of the 3" studs. As long as there is 1/2" of threads on the head of the lugnut (clamping part) holding your wheel on you should be fine. I had my wilwood rotor hats machined .100" on the face that the wheel rests because of this issue. I have not had a problem with tech with this setup
 
Thank You

The thread engagement on all wheel studs to the lug nut, or lug bolts to
wheel hubs, must be equivalent to or greater than the diameter of
the stud/bolt. Length of the stud/bolt does not determine
permissibility. (Example: A 7/16-inch stud must be thoroughly
engaged through the threads in the hex portion of the lug a
minimum of 7/16-inch.)

from 2012 Nhra rule book...

the stud does not need to go thru the open end of the lug nut....must engage the hex part of the head of the lug by at least the diameter of the stud...as noted in the example....my 71 demon with strange brakes and 3 inch studs do not go thru the end of the lug nut...passed tech in Vegas, Fallon and now Sacramento.
 
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