Spacers to widen the stance of stock 21" wheels?

[Roots]

Can spacers be installed to move the stock 21 wheels/mags out a little? What affect will it have? Has anyone done this? Current stance seems skinny. How will Performance change by pushing mags out a little, and is it safe? Seems like tons of room in the wheel well! Not looking to lower, just wondering about a little wider stance for these massive 21s.

 

[63MM]

Longer studs will also be required as well. I've been searching around and while there are plenty of universal style spacers available, I have yet to locate longer studs. Ultimately I would love to find a vendor that sells both as a package. Maybe someone here who has some luck will chime in.

As for safety concerns wrt spacers, I use them on all of my vehicles and have yet to run into any problems. That said, there are a few comments/threads online that warn against the use of them.

 

[GTP]

Can spacers be installed to move the stock 21 wheels/mags out a little? What affect will it have? Has anyone done this? Current stance seems skinny. How will Performance change by pushing mags out a little, and is it safe? Seems like tons of room in the wheel well! Not looking to lower, just wondering about a little wider stance for these massive 21s.

I plan to check if 1/4" spacers will work without longer studs. You just need to have 7T thread engagement, or 10mm minimum. I suspect it will be OK. If so, I will order them from CJ Pony Parts. Their house brand spacers are great, $40/pr.

I had to go to 1/2" longer studs on my Mustang in order to run high offset wheels for track days. That was a hassle, one I won't repeat for the ST.

I don't believe 1/2" wider track will affect performance at all. It seems like not much offset, but you WILL notice the better stance with that small change.

I also plan on Ford splash guards for the winter, and so I don't want the wheels fully flush with the fenders.

 

[UNBROKEN]

1/4” spacers are fine and leave just enough hub protruding in the rear to maintain the hub-centric fit of the wheel. Not sure on the front as I don’t plan to use one up there.
You would only need longer studs for a slip on spacer 1/2” thick or more and anything bigger than that as a slip on is a bad idea anyway.
If you want to widen the track look at Bora bolt on spacers. Just remember the rear wheels are inset 1/4” further than the front. The front wheel is right at 7/8” from the outside of the fender to the lip of the wheel, 1 3/8” out back.
You could do a 5/8” bolt on spacer up front of you shortened the studs and a 1” spacer out back to have an almost identical track width and that would put the outside of the tire about dead even with the outside of the fender.

 

[GTP]

@UNBROKEN, good to know about the f/r difference. Now I'll just get spacers for the rear!

 

[GTP]

I verified that the rear tire is tucked about 1-1/4" in from the fender, and the front tire is tucked by 1".
I removed one lugnut from the front and one from the rear. I measured the thread depth (end of stud to bottom on wheel cone). It is 24-25mm for both axles. There is 17mm of threads inside the OEM lugnut. This means that there is 7mm to spare for a spacer, and still have FULL thread engagement. So a 1/4" spacer should be safe with the OEM studs.

However, a 1/2" spacer would leave 24-13=11mm thread engagement, and that should still be barely sufficient. (7 turns = 10mm.) This means that 17-13=4mm of the lugnut threads would not be engaged with the stud.

 

[UNBROKEN]

Keep in mind a 1/2” slip on spacer will eliminate the hub centric fit of the wheel...you’ll essentially be making them lug centric which can lead to vibration issues.

 

[BAD430BENZ]

I would not do a slip on spacer

 

[GTP]

The CJ 1/4" spacer is bore centric, and the 1/2" has an extended flange to also make it bore centric.

I ran a set of 4 of the 1/2" spacers on my Mustang at the road course up to 130mph, and all was smooth. (Note this setup has 1/2" longer studs and open-ended lugnuts.)