Well i have a few sets of aluminum slots and my dad needs a set for his slicks on his chevelle, (5x4.75 pattern) one set i have that were actually on my comet when i got it, they have the oval shaped hole. unilug rims, is it super dangerous to run these with slicks for any reason or will it be fine?
I would never run slicks or any other tire that I planned on doing any racing with on Uni lug rims. I don't believe NHRA would allow it either. If it is on a car just for the look, then fine. But otherwise I wouldn't do it.
Personally, if it is a low HP engine, maybe under 300 Hp, probably won't hurt. But anything stronger, like a moderately built 302, nope! I have a set of rims with slicks on them for the track that I do not use for the street. I nail it hard on the street, and the unilugs hold up, but at the track, I swap out the rims that have the slicks on them. Really light aluminum rims that break free quickly.
Well 3 people say No so it'll be a no! don't need my dad crashing his car..it's prob 450-500hp..when purchased the engine was supposed to be a bit over 500 @the wheels but it needs a refreshing. for the 40 bucks it'll cost me to get some steelies..well worth it. thanks guys for the info
The only thing wrong with a unilug wheel is the person installing it. First, people tend to use whatever lug nut they find that seems to fit. The lug needs to be the proper style for the wheel and fit tightly in the hole of the wheel. A unilug wheel is stud concentric not hub concentric so it has to be the right stud/nut combination. The nut shank must also go as far into the wheel as possible without contacting the wheel hub/drum face. You want minimal air gap beween the end of the nut and the axle flange. If the wheel is 7/8 thick at the hole, don't use a 1/4" long shank stud, use a 3/4" shank. On the flip side, don't run a 1 inch long shank in a 7/8" thick wheel, you will never get it tight. Never run a standard taper seat lug on a unilug wheel unless the washers are made for a taper seat nut with a shank, like an E/T wheel uses. Secondly, you also need to be sure you have a long enough wheel stud to get the proper amount of stud in the lug nut. A minimum of 1x the diameter of the stud needs to be inside the hex of the lug nut. Most stock lug studs are too short to do this with an aftermarket aluminum wheel. Use a good 3" stud and a lug nut that lets the stud go clear thru and you will have no problem there. The third offense is the washer used. Some wheels require specific washers. Again people tend to use what hey have access to. There are also a very wide range of wheel washers. Use the wrong, thin, cheapo wheel washer and it will "cone" down into the unilug hole and never torque correctly. Also, if the washer fits a machined recess sloppy because it has been run loose and egged out the washer seat, the wheels are junk. Lastly, like any fastener, it needs to be torqued when installed and re-torqued after a few miles. You then need to check it occasionally. People say the NHRA will not allow unilug wheels. I can't find it in their rules. They do address the amount of engagement in the wheel stud but nothing is said about a unilug wheel that I can find. I would not hesitate to run them. Use the proper nuts, washers and installation and you will have no problems. The only unilug wheel I have ever seen that broke studs was installed incorrectly. It had the wrong washers and they had coned into the hole so the wheel was actually running loose on the hub a long time before it broke studs. Operator error. I run them, but I run them correctly. I have not had a single problem with them in the last 38 years that I didn't create myself. Millions have been sold and used thru the years, of course there will be failures reported. Taper seal wheels and bolt pattern specific wheels fail also. SPark
At the tracks I have been to, they want to be able to see the stud so they can verify that enough stud is in the lug nut. The unilug wheel lug nuts that I have seen have big acorns on them, so you cannot see the stud. That alone will get you kicked off the track.
I just use a cutoff wheel and cut the top crown of the nut off. That lets the long stud stick clear thru the nut. Takes about 20 seconds per nut. Done it several times. You sometimes need to chase the threads at the new open end of the nut to cut them clear thru. That's what I've done to get the right nuts on my current Maverick project. Also, according to NHRA rules, they don't need to stick thru, they need to extend into the hex portion of the nut at least the same amount as the diameter of the stud. That's easy to check if 1 nut is removed for measurement. Sticking clear thru is not required by the rules but is a much easier way to tech things for a lazy tech man. SPark
i had 3" studs put on my moser rear end..and cut the ends off the nuts as well and chased them..the fronts i left stock length as they just make me pull one off to check it out. back to the uni-lug rims..i have all the proper washers for them and would have to get new nuts; the right length. Also the lug nuts fit very snug inside the rims, no slop at all,but i'm trying to find a set of steelies because id rather just use them, easier..but i put an add out for the most common steel rim ever..and nothing yet..one person had 2 but they were to narrow for the slicks..wouldn't you think a ton of people would have 5x4.75 8" wide chev rims sitting around? seems impossible right now lol..only found one set of 7" but the slicks are 10.5 wide.
Years ago I used Cragar SS wheels, with unilugs to mount 9" slicks on my '77 Mav, with a real good 302. One night, it hooked up real good, broke the centers out of the wheels, and bent the quarters up a bit. Haven't used them for anything since. Leave the unilugs to the street and show n shine crowd, that is where they belong. Use a strong, purpose built wheel for racing.
What you describe isn't a unilug issue, it's a wheel issue. I have seen several Cragar SS wheels that broke on a Coats 10-10 or 20-20 wheel machine thru the years simply by breaking the bead. These wheels were very brittle. I saw one rip the center out of the wheel when the bar rotated to remove the tire. I was in high school in the early 70's and I don't honestly think I had a single friend with Cragars that didn't break a wheel at one time or another. I worked for a Uniroyal/BF Goodrich dealer and he forbid the use of a tire machine on Cragar SS wheels, nothing but manual labor on them. I love the looks of the Cragar SS but it is probably the junkiest wheel ever built as far as strength went. That said, they were a popular wheel on early drag cars and lived well at the time. While this isn't a Maverick/Comet, and the wheels were not unilug it appears, this guy regularly punished them for a few years. The reason I say this is not to argue with you. It is simply that somebody has a problem with a wheel, it is a unilug so that becomes the problem. The fact that the wheel was unilug most likely had nothing to do with it but it has become a montra of sorts to blame that aspect of a wheel when it is most likely another issue causing the problem. Ripping the center out of a wheel is not a unilug problem, it's a wheel problem. JMO, SPark
Just to clarify...................IM14 is correct about the unilugs..............I had some on my 64 Impala and they were a great wheel. Currently I don't believe NHRA will let you race with Unilug wheels though........some myths turn into reality for NHRA!
If you have a current NHRA rules book, I would appreciate knowing if it is actually in there. This was a big discussion on the Yellow bullet site a while back and when push came to shove, nobody could actually find it. I know it wasn't in the 2010 general regulations. Maybe it's a class rule or time/speed rule but nobody can find it to actually quote it. http://www.nhra.com/UserFiles/file/General_Regulations.pdf Section 5.2 is wheels. I've also been told NHRA won't allow wheel spacers but it's right there in black and white that they do. On another board I read where the Chevy guys couldn't run stock 7/16 studs and had to upgrade to minimum 1/2" studs, but that is the example quoted in the wheel section. It uses a 7/16 stud as the example of engagement. I'm getting really curious about this, is it a fact or myth? Seems to be a lot of myths surrounding the NHRA rules these days. Thanks, SPark
That is the same section, word for word as my 2012 rule book states....I'm a current member but have not seen anything other than an addendum to the 2012 for 2013. The last time was at an NHRA track the guy next to me had some Unilugs on the rear of his Camaro (ole SS car) and the NHRA Tech guy told him he would allow it for this race only, but next time he could not use them to race............................I didn't hear the whole conversation but did here him say only this one last time! Remember, the rule book is only a guide line and it is the NHRA Tech that can say yes or know.....................same as when I was a SCCA Tech.... when you are putting your signature on the card..................if there is an accident you are in the hot seat!!!!!!!!!!!!!!! I would run them on the street but would never run them on the track.... period! Almost everyone I know who has a somewhat serious race car uses SFI cert'd wheels.......................cheap insurance......................IMHO And yes, you should be running 1/2" studs minimum.......................some NHRA Techs will not allow Grade 8 Hardware store studs for rear wheels................................I wouldn't use them either!
