I got me a couple sets of spacers for all four OEM 18" wheels for a flush look and better handling. 20mm front and 25mm rear. A friend told me that spacers are merely for aesthetics and that they aren't reliable especially when tracking them. If so, does that matter if my coupe is a daily driver and used as an occasional joyride or am I just being a worry wart? I'm just worried about my wheels falling off out of nowhere.

 

Just need to install them properly and re check torque after the first 100 miles then every oil change. If they're a name brand spacer they should hold up just fine. Also only use a 6pt socket when installing bolt on spacers, the nuts round off very easy.

 

and you could always have extended studs pressed and use slip on spacers if you are truly concerned. Almost zero chance of issue unless you don't have long enough studs put in for the spacers to allow your lug nuts to have enough thread engagement (tough to do as most slip on spacers come with studs haha).

Basically, the route above (instead of stud/spacers all in one options), negates the need to go back and re-torque the lugs on the spacers themselves after installing them after (as blnewt mentioned) 50-100 miles. You just operate under normal pretenses and re-torque the wheel lugs themselves after 50-100 miles.

Process with stud integrated spacers for full assurance? Take wheel off again (after 50-100 miles following the install), torque lugs on spacers that keep it tightened to the hub, put wheel back on......after 50-100 *more* miles, then you retorque wheel lugs.-- Does everyone do this? No. Does it spell immediate doom if they do not? Probably not...but if you want to take all precautions...that's what you're in for. My vote, install extended lugs and slip on spacers. I pressed ARP studs with a friend, but was surprised at the lower costs shops were quoting to press them into the hub for me after I went through the process (especially if you're having your rotors replaced--that's when I did mine out in the garage).

I've been running either type of spacers for the past 8 years across three different vehicles, nary an incident.

 

I have been running 20mm spacers with extended studs on my FX35 w/ 20" wheels for six years & 90k miles with no problems. I regularly drive in the mountains and tow a boat. As an engineer I recommend going with spacers w/ extended lugs over the adapter-style spacers.

 

I'd imagine there's a point where extended stud setups would not be the best plan as far as going too thick w/ the spacer and then requiring very long studs, not sure what that point would be though

 

Thanks for the input guys. I just recently installed H&R wheel spacers so yeah I guess I should be good. I'll check and retorque the nuts after said miles.

 

Here is a before & after for you guys:

Before:


After:


Just for laughs

 

Nice fit!

 

great fit

 

Wheel spacer safety, and the physics of keeping the wheels on

Are wheel spacers safe?

Yes. When properly installed they are just as safe as wheels installed without spacers.

Will wheel spacers cause my wheel studs to bend?

No. The load from a wheel is transferred to the axle/hub through the friction of the clamped joint, not through the wheel stud. A wheel stud can only bend if the lug nuts are not properly torqued, in which case the wheel is about to fall off, anyway.

The Physics of Keeping the Wheels On

As long as the wheel, hub, and spacer are stiff enough to prevent flexing and loss of clamp force, the cause of most wheel stud failures is under tightened lug nuts (not enough clamping force) or over tightened lug nuts (the stud has been stretched past it's elastic limit, so the clamping force goes away). Therefore, properly installed wheel spacers are perfectly safe.
The wheel stud applies a clamping force that holds the wheel to the hub. When the lug nuts are tightened, the wheel studs stretch elastically, like very stiff springs. The lug nuts should be tightened until the stud is at 90% of its elastic limit. This will provide the greatest possible force to hold the wheel to the hub.
The amount of clamping force at a joint is important because of the coefficient of friction (Cf). The more clamping force applied to the joint (in this case the joint between the wheel and the hub), the more force required to make the wheel slip relative to the hub. Unless the wheel slips on the hub, there cannot be any bending load on the stud.
Coefficient of friction -- There is friction between the wheel face and hub face. This friction can be measured, and it is called the "coefficient of friction". The coefficient of friction (Cf) is the ratio of normal force, at the intersection of two surfaces, to the lateral force required to slip the bodies relative to one another. As an example, good street tires have a Cf of 0.9. This means that if there is a 100-pound vertical force applied to the tire, the tire can generate 90 lbs. of cornering force before it slides.
When the car starts moving, the stress applied to the stud does not change appreciably, unless one of two things happens:
The vertical component of any external force applied to the wheel is so great that the clamping force is not sufficient to hold the wheel in place, and it slips on the hub. At this point the stud is loaded in bending and in shear, and may yield, or even break.
Some portion of the clamped joint, wheel, or hub is not stiff enough to prevent flexing, and allows the tension load on the stud to drop to zero. With no tension load on the stud, the clamped joint is no longer tight. The wheel can then move relative to the hub, and place a bending load on the studs.
Inserting a wheel spacer between the hub and wheel changes nothing about these physics.
The hub center of a hubcentric spacer does not hold the spacer on the hub or reduce the chance of stud failure. There is never any load on the lip of the wheel spacer. For there to be a load on the lip, the friction force in the joint must have been completely overcome. The lip on a hubcentric wheel spacer serves only as an aid for wheel installation.
Increasing the length of the wheel studs to use a wider wheel spacer has no appreciable effect.

 

Like others i trust the spacers with exstended studs installed.inchiba v1s is what i use....

 

Here in the Netherlands they are not allowed for several reasons. Although I've seen them, it's only for the looks and with everything you need to like it. I personally do not like them for three reasons.
Wheel spacers destroy the balance of your car. And the wheel bearings will wear excessive. Wheels which are sticking out looks terrible.

 

They definitely improve the stance with the OEM wheels on the coupe. A colleague of mine at work turned me onto this concept a while back when I asked him why his coupe looks so much better than others I've seen (less pronounced wheel gap)

But of course, this comes with some tradeoffs, which is why manufactures probably do not recommend or install them. If you are a 'car aware' type like most of us, and maintain them on a regular basis, you are probably fine. If you are like most people and only pay attention to your car when something is scraping, wobbling or howling, then they are probably not the right mod for you.

 

But what do you want to maintain on wheel spacers?