Maximum rear wheel spacer vs. safety issues

Rusty Davenport · 06-17-2013, 11:24 AM

Using aftermarket 5/8 rear wheel studs, would 1" thickness wheel spacers be too much for safety on a stocker ??? What would be the maximum ???

GTX JOHN · 06-23-2013, 05:43 PM

Yes!!! I broke a bunch of ribs and knocked down the tree and destroyed
a car at the Winters' with 1/2" billet spacers.......Just my opinion.

Dragsinger · 06-23-2013, 06:05 PM

Rusty, there are always "conditions/exceptions"

From personal experience S & W will build water jet cut aluminum spacers at least 1" thick. I have a 1" set on a dragster that runs 4.80's and a 3/4" set on a door car that runs 6.10's

I know others who also run thick spacers. I think the key is a spacer that fits the studs exactly/snugly and checking wheel nut torques OFTEN! I think it is possible that some lug stud failures happen because the tightening torque is not checked and the fastener per-load becomes insufficient.

Run to Rund · 06-23-2013, 08:44 PM

Please get the correct offset wheel instead. Even if bodywork doesn't bother you, the guy next to you will be grateful.

Bob · 06-23-2013, 11:30 PM

From the rule book:
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.)
Wheel spacer permitted. Spacer to be either hub-centric or lug-centric
and must fit with minimal clearance to retain concentricity. The wheel
spacer must not reduce the minimum permitted thread engagement
below the limits established by fastener diameter.

Although it's legal, as others pointed out, it may not be safe. The correct offset weels would be better.

Sean Marconette · 06-24-2013, 10:21 AM

The key to running spacers is what Larry pointed out. They need to fit snug on the wheel stud, and have adequate torque applied. The 5/8" studs do not allow for a shoulder style lug nut. The problem with running spacers with 1/2" studs, is the engagement of the lug nut shoulder allowing flex in the stud. If the stud is allowed to flex, you will have bad things happen. After having 4 out of 5 wheel studs break when I first got my car back together several years ago, I was running 1/2" studs with spacers. The stud was flexing at the brake rotor hat, as the lug nut shoulder did not engage in the full depth of the spacer. Since switching to 5/8" studs and billet spacers, I have never had an issue. When servicing the brakes, I have to work the spacer off the studs to remove them.

Get the tire and wheel to fit the car with spacers, then if you choose to buy a custom offset wheel you know exactly what you need.

Sean

06-17-2013, 11:24 AM	#1
Rusty Davenport Senior Member Join Date: Jun 2005 Location: Nashville N.C. Posts: 506 Likes: 4 Liked 101 Times in 27 Posts	Maximum rear wheel spacer vs. safety issues Using aftermarket 5/8 rear wheel studs, would 1" thickness wheel spacers be too much for safety on a stocker ??? What would be the maximum ??? __________________ NHRA AND IHRA STOCK ELIMINATOR 2772

06-23-2013, 05:43 PM	#2
GTX JOHN VIP Member Join Date: Jun 2009 Location: Boulder City, Nevada 89005 Posts: 2,720 Likes: 2,770 Liked 2,436 Times in 688 Posts	Re: Maximum rear wheel spacer vs. safety issues Yes!!! I broke a bunch of ribs and knocked down the tree and destroyed a car at the Winters' with 1/2" billet spacers.......Just my opinion. Last edited by GTX JOHN; 06-24-2013 at 06:58 AM.

06-23-2013, 06:05 PM	#3
Dragsinger VIP Member Join Date: Jul 2008 Location: Liberty City [East Texas] Posts: 1,760 Likes: 5 Liked 99 Times in 60 Posts	Re: Maximum rear wheel spacer vs. safety issues Rusty, there are always "conditions/exceptions" From personal experience S & W will build water jet cut aluminum spacers at least 1" thick. I have a 1" set on a dragster that runs 4.80's and a 3/4" set on a door car that runs 6.10's I know others who also run thick spacers. I think the key is a spacer that fits the studs exactly/snugly and checking wheel nut torques OFTEN! I think it is possible that some lug stud failures happen because the tightening torque is not checked and the fastener per-load becomes insufficient. __________________ Larry Woodfin 471W

06-23-2013, 08:44 PM	#4
Run to Rund Senior Member Join Date: Sep 2007 Location: Henderson, NV Posts: 583 Likes: 8 Liked 54 Times in 27 Posts	Re: Maximum rear wheel spacer vs. safety issues Please get the correct offset wheel instead. Even if bodywork doesn't bother you, the guy next to you will be grateful.

06-23-2013, 11:30 PM	#5
Bob Junior Member Join Date: Oct 2003 Posts: 48 Likes: 0 Liked 0 Times in 0 Posts	Re: Maximum rear wheel spacer vs. safety issues From the rule book: 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.) Wheel spacer permitted. Spacer to be either hub-centric or lug-centric and must fit with minimal clearance to retain concentricity. The wheel spacer must not reduce the minimum permitted thread engagement below the limits established by fastener diameter. Although it's legal, as others pointed out, it may not be safe. The correct offset weels would be better.

06-24-2013, 10:21 AM	#6
Sean Marconette Senior Member Join Date: Mar 2006 Posts: 977 Likes: 787 Liked 274 Times in 76 Posts	Re: Maximum rear wheel spacer vs. safety issues The key to running spacers is what Larry pointed out. They need to fit snug on the wheel stud, and have adequate torque applied. The 5/8" studs do not allow for a shoulder style lug nut. The problem with running spacers with 1/2" studs, is the engagement of the lug nut shoulder allowing flex in the stud. If the stud is allowed to flex, you will have bad things happen. After having 4 out of 5 wheel studs break when I first got my car back together several years ago, I was running 1/2" studs with spacers. The stud was flexing at the brake rotor hat, as the lug nut shoulder did not engage in the full depth of the spacer. Since switching to 5/8" studs and billet spacers, I have never had an issue. When servicing the brakes, I have to work the spacer off the studs to remove them. Get the tire and wheel to fit the car with spacers, then if you choose to buy a custom offset wheel you know exactly what you need. Sean __________________ Sean Marconette 84 Mustang 5060 SS/N