Can we talk about *GASP!* Wheel Spacers?!

I'm looking to put FD wheels on my FC RX-7.  I need a 20 mm spacer.  Now, I understand that there are those that maintain that it is unsafe to do so--That any car with any wheel spacer will spontaneously immolate, killing the driver and anyone near it.

However, there is an opposing school of thought that asserts a spacer of modest thickness is perfectly fine.  I'm interested in hearing from those people.

There appear to be two kinds of spacers:  a flat ring, with an appropriate number of holes.  This would require that I install longer wheel lugs, as my lugs extend but an inch, leaving insufficient threaded length to properly secure lug nuts.

The other kind uses the existing studs to mount a ring which secures "new" lugs in the space between the stock lugs.    The only catch here, is that if the wheels being mounted do not have a recess to accommodate the part of the stud which extends through the spacer, the wheel will not set flat against the mounting surface and will need to be shortened.

So, does it matter which way I go?  Are some brands better than others?  Can anyone recommend a source?

Thanks!

I ran 2" spacers on the truck on all 4 corners. no one died. 

Properly installed a wheel spacer is safe. 20mm is too short to bolt on then have additional studs, you should use the appropriate longer studs. The spacers should have holes very close (+.010 dia max) to the size of the studs.

I ran 1” spacers on the front of my autocross ae86 for half a season plus daily driving. Nobody died but my wheel bearings were rather unhappy.

20mm is right on the edge for being able to use bolt on spacers (it'll depend on wheel design).  I'd probably go with extended studs and slip on spacers for that size, although I do have 19mm (3/4") bolt on spacers on the front of the Jeep (the wheels I have for it all have enough of a recess for the studs).  My 25mm rear bolt on spacers sit pretty flush with the nuts.  

1" spacers on the rear of my daily driver Mustang haven't killed anyone yet. 2" spacers on the front of a friend's '92 Camaro haven't caused any deaths yet either.

Both are of the bolt on variety.

As long as you arent out pounding kerbs on a track all the time I would think its safe, even for autocross, as long as you get good studs (ARP, etc) with sufficient engagement. 

I used 1.25" adapters on a 4400 station wagon, drove it 2,000 miles round trip to the Challenge, raced the Challenge, and it was fine. Sooo worth it to have C4 Vette wheels on a Roadmaster.

These are run all the time in Lemons.  You never really hear or see failures.  One time someone didn’t get a flush seat on the whee adapter which made it come loose as it couldn’t be torqued properly.  If you have long enough studs (and strong enough) for proper thread engagement, it will be fine.  

If you mount ARP extended studs in good quality hubs. You should have no issues. I am not a fan of the bolt on spacer "hubs" 

But I have no experience with them. They just don't give me warm and fuzzies thinking about what chinesium the new stud may be made of...

Land Cruiser guys run up to 2" spacers all day long on a 6800lb SUV going offroad with a whole bunch of horsepower and gear reduction.  I would have no concern with quality spacers properly installed.

I use ARP extended studs on my daily driver. The spacers are have a milled hubcentric center, which keeps any play from happening.

I also happen to have two bolt on 114.5 bolt pattern 15mm spacers sitting in my garage doing a whole not of nothing at the moment. If a 15mm spacer would work vs. a 20mm, let me know.

 

I have hubcentric 1.25" bolt-on spacers on my 4k+ lb SUV with no issues.

Spidertrax is big in the offroad world but I'm sure there are plenty of reputable companies making them for more sportcar-type applications.

I was just skimming the SCCA TT rules to make sure the MGB would be okay with spacers, and they're fine under tuner and sport rules, for whatever that's worth. They may be fine under other groups, I just didn't look anywhere else.

Regarding the earlier comment about wheel bearings, that's not about spacers per se, but about the effective offset of your wheels and spacers together. I'll be using wheels with more offset than would normally fit, with 13 and 16mm spacers (rear and front, respectively) to make them more or less correct, inasmuch as correct exists for a 7" wheel on this car.

I'll also be using new Moser studs.

Anybody know if these M12 x 1.5 ARP studs will fit my stock hubs?

ARP #100-7713

Whatever style spacers you get, "sandwich" type with long enough studs or adapter style, make sure to get the ones that are hubcentric.

I ran bolt-on spacers for the rear axle of my Mustang for 40k miles of teenage daily driving, mountain runs and autocross without ever having an issue. The previous owner installed them with low profile nuts and the studs cut down. I was 16 at the time and didn't know any better, but I'm still alive. 

There are very few aftermarket wheel options for my Jag... but adding 20mm spacers would allow me to run choose from among the hundreds of wheels options available for the Ford Focus RS.  Seems worth investigating.

Sonic said:

These are run all the time in Lemons.  You never really hear or see failures.  One time someone didn’t get a flush seat on the whee adapter which made it come loose as it couldn’t be torqued properly.  If you have long enough studs (and strong enough) for proper thread engagement, it will be fine.  

You do sometimes see problems when people use impacts to set lug nut torque on the spacer *cough*Bruce*cough* but that happens without spacers, too.

Volvo 240/740s at 5x108 +20 generally needs spacers to run anything other than stock or custom wheels which generally exceed the value of the car. Guys on the Volvo forums tend to run screaming fearing Cthulhu at the mere mention of spacers, but in the real world most people seem to fare just fine. 

as long as you have appropriate-length studs, you can hit all the things you want and your wheel barrel will break long before the spacers become an issue. Source: 9 years of hitting things and jumping, using spacers. between 8mm and 20mm, with zero issues (well, zero issues related to spacers, at least)....

like any modification, if you do it properly, it will do just fine.

nderwater said:

There are very few aftermarket wheel options for my Jag... but adding 20mm spacers would allow me to run choose from among the hundreds of wheels options available for the Ford Focus RS.  Seems worth investigating.

Even better, the bolt on spacers can be made to adapt to different bolt patterns and/or center bores. 

Did someone say wheel spacers?

https://www.youtube.com/watch?v=LN-OJYKhOHU

I had 20mm hubcentric spacers  on my mazda 323 gtx. I didn'r rally the car on those spacers but saw no problems normal driving on my "fancy" street wheels. 

My E55 monster came to me with Brabus wheels along with all the other spendy stuff, and they required 20mm hubcentric spacers. And things have been sorta uncertain from the getgo. We replaced a lotta suspension bits which is a good idea, but I noticed that  torquing the wheel bolts to like 150 ftlb seemed to help. Hmmm. Well, I picked up a low speed under-braking clunk. Pull a wheel. The spacer holes are at least a qtr inch bigger than the bolts. And the bolts had *carved thread grooves* into the spacer holes. Well, that is what we call alarming. That braking clunk was the wheel rotating fwd until stopped by the bolts. There are set of sl55 wheels on it now and literally everything is better about the entire car. So on an rx7 at stock or near enough output, yeah no trouble. But on a two ton teutonic tessie that violates the laws of physics, no freaking way...

The car doesn't know know the difference between 1" spacers and wheels with 1" less offset. With decent wheel studs and proper torque, there's like 60 tons of clamping force between the wheels and the hub. Lots of other stuff is going to fail before those spacers do.