[HCI2000SS]

Does a wheel with say a 32mm offset cause the same exact overall stress as the exact same wheel again, but with a 35mm offset, and with a 3mm spacer added, making it 32mm again? So basically both wheels are exactly the same diameter, width, and design in this scenario.

[Mark114]

One issue is that spacers can reduce the lug nut thread depth and at some point that becomes dangerous.

[HCI2000SS]

Originally Posted by Mark114

One issue is that spacers can reduce the lug nut thread depth and at some point that becomes dangerous.

Yes I definitely knew that, but in the scenario above I'm almost positive that it won't be an issue. I'm just wondering if things like wheel bearing and suspension wear will be basically identical over time

[foshjowler]

I think a spacer will add more wear on bearings and the such as compared to the equivalent wheel offset. It's adding more weight to the equation, and moving the center of weight on the wheel out. That being said, a 3mm spacer would be pretty negligible. I wouldn't put too much thought into it.

[HCI2000SS]

Originally Posted by foshjowler

I think a spacer will add more wear on bearings and the such as compared to the equivalent wheel offset. It's adding more weight to the equation, and moving the center of weight on the wheel out. That being said, a 3mm spacer would be pretty negligible. I wouldn't put too much thought into it.

My thoughts are the same with a 3mm spacer, but I was wondering if anyone had done any actual testing on something like this. BTW, does anyone know a good place to buy them? ZL1 Add-ons has them, but they are like $50. Seems kind of crazy for 2 pieces of 3mm metal

[Alpha1BC]

I'd actually argue that it won't change anything measurably except for lug strain from thread engagement as Mark mentioned.

From a load standpoint, your load application point (i.e. contact patch) and the vehicle reaction point (where loads are transferred into the rotor face/hub) are in the exact same spot in both cases. That means all your loads and moments are going to be the same in each case from the perspective of all the OE vehicle components. It doesn't matter what's between the contact patch and the rotor/hub face in this scenario unless it drastically changes mass or stiffness, which spacers typically do not.

From a mass standpoint, you're not significantly changing the mass because there has to be material added or removed somewhere to make up the difference. We're also talking on the scale of ounces for spacers that small, nothing out of the range of what could potentially be added for balancing wheels even. Inertia will be slightly impacted since wheel CG will be slightly different, but like the additional few ounces of mass it won't have any meaningful or measurable impact to overall loads going into the vehicle since worst case loading is heavy impacts like potholes. Same could even be said for larger spacers like 1" and even larger to a point; mass and inertias won't change enough to cause any measurable difference to stress for the bearings and other vehicle components. You'll likely get a bigger mass/inertia change from swapping away from OE wheels than you will from adding a spacer, and that also wouldn't negatively impact it.

For where to buy I'd suggest amazon or ebay. Would expect you can find some cheap no-name ones there that will do the job without issue, just have to find one with the right bolt pattern and large enough center bore.

[gotswap]

No extra strain whatsoever, just wheel stud engagement as you already know

[HCI2000SS]

Originally Posted by Alpha1BC

I'd actually argue that it won't change anything measurably except for lug strain from thread engagement as Mark mentioned.

From a load standpoint, your load application point (i.e. contact patch) and the vehicle reaction point (where loads are transferred into the rotor face/hub) are in the exact same spot in both cases. That means all your loads and moments are going to be the same in each case from the perspective of all the OE vehicle components. It doesn't matter what's between the contact patch and the rotor/hub face in this scenario unless it drastically changes mass or stiffness, which spacers typically do not.

From a mass standpoint, you're not significantly changing the mass because there has to be material added or removed somewhere to make up the difference. We're also talking on the scale of ounces for spacers that small, nothing out of the range of what could potentially be added for balancing wheels even. Inertia will be slightly impacted since wheel CG will be slightly different, but like the additional few ounces of mass it won't have any meaningful or measurable impact to overall loads going into the vehicle since worst case loading is heavy impacts like potholes. Same could even be said for larger spacers like 1" and even larger to a point; mass and inertias won't change enough to cause any measurable difference to stress for the bearings and other vehicle components. You'll likely get a bigger mass/inertia change from swapping away from OE wheels than you will from adding a spacer, and that also wouldn't negatively impact it.

For where to buy I'd suggest amazon or ebay. Would expect you can find some cheap no-name ones there that will do the job without issue, just have to find one with the right bolt pattern and large enough center bore.

Thank you for the detailed answer. That makes good sense. Let me ask you this...does it matter if the center bore on the spacer is larger than it is on the hub bore, or should it be the same size for a more exact overall fit? Also, the cheaper spacers on eBay and whatnot, are they going to be just as good over time, say like over the next 5 to 6 years? I realize I need the correct bolt pattern, but just wondering if there's really any advantage to the more expensive ones when we are talking about a spacer as thin as 3mm

[HCI2000SS]

Originally Posted by gotswap

No extra strain whatsoever, just wheel stud engagement as you already know

Yep and from everything I'm seeing 3mm won't be an issue on the Camaro.

[Alpha1BC]

Originally Posted by gotswap

No extra strain whatsoever, just wheel stud engagement as you already know

Just to clarify, I say strain because fewer threads engaged with the same torque will net *slightly* more stress/strain in the threads if there are fewer than 6 threads engaged. But, it's nothing significant as long as you have at least 3 threads engaged. Not strain in the lug body mind you, but strain in the threads themselves.

Originally Posted by HCI2000SS

Thank you for the detailed answer. That makes good sense. Let me ask you this...does it matter if the center bore on the spacer is larger than it is on the hub bore, or should it be the same size for a more exact overall fit? Also, the cheaper spacers on eBay and whatnot, are they going to be just as good over time, say like over the next 5 to 6 years? I realize I need the correct bolt pattern, but just wondering if there's really any advantage to the more expensive ones when we are talking about a spacer as thin as 3mm

No problem, I kinda nerd-out on engineering stuff like this so happy to chime in when it's relevant haha. It doesn't necessarily have to be spot on for center bore, though. All the center bore does for is center the spacer/wheel prior to torqueing the lugs down. For the spacer, if you've got close to a 14mm hole (like 15 or 16mm) that fits over the lugs it'll end up mostly centered on the lugs anyways. The wheel will be centered by the conical/tapered lug nuts so don't necessarily need the wheel on the center bore either, just might need to prop it up when the first lug nut or two goes on to keep sockets from rubbing the wheel. Worst case it'll cause a little imbalance, but since it's so little mass close to the axis of rotation I'd wager any imbalance from an off-center spacer wouldn't really be noticeable.

As for the cheaper vs. more expensive spacers, main difference is likely manufacturing location which impacts quality control. More expensive ones are at likely coated and/or machined in the US and material might even be US sourced as well which is typically more expensive but more consistent in terms of quality. Tolerances are probably a little looser on the on the cheaper one (like ±0.1mm instead of 0.01mm) and material might not be as high of a grade, but at the end of the day it's just a piece of aluminum sandwiched between the wheel and rotor face. As long as it's flat/parallel enough and fits over the lugs there shouldn't be any issues. It's a pretty easy manufacturing process and material quality of stuff coming from low cost-of-production regions has significantly improved over the last 5/10 years, so the risk of getting crummy parts is pretty low.

Originally Posted by HCI2000SS

Yep and from everything I'm seeing 3mm won't be an issue on the Camaro.

Correct, a 5mm spacer seems to be about the threshold from my experience and others I've seen on here before wanting to look for longer studs. Will vary based on wheel and aftermarket lug design, though. I had 3.5 threads engaged on an Apex wheel with a 5mm spacer. Did a few track days on it and had no issues but swapped to Silverado studs to get the extra 3mm length just to be safe when I had everything apart for a brake job.

[Mark114]

Originally Posted by HCI2000SS

Thank you for the detailed answer. That makes good sense. Let me ask you this...does it matter if the center bore on the spacer is larger than it is on the hub bore, or should it be the same size for a more exact overall fit? Also, the cheaper spacers on eBay and whatnot, are they going to be just as good over time, say like over the next 5 to 6 years? I realize I need the correct bolt pattern, but just wondering if there's really any advantage to the more expensive ones when we are talking about a spacer as thin as 3mm

I bought my hub centric spacers on Amazon. I got the correct bore size to avoid the hassle of trying to center a cheap spacer for wheel balance. I also went with solid spacers that only had holes for the studs to have a solid mounting surface for the wheels. Some of the less expensive spacers have more cutouts that reduce the mounting surface area and possibly heat transfer from the hubs to the wheels. Finally you don’t want a cheap material that might crush or deform under load.

[TheRealJA105]

Alpha explains it well and I agree with him on cheap spacers up to probably 7mm. When going to 12mm or larger spacers (obviously with extended studs) i would say to pay extra for the proper hub-centric spacers to keep the wheel centered perfectly as they are thicker than the stock hub protrusion.

I run Ebay 5mm spacers for a BMW hub and have Motorsport-Tech 12mm hub-centric Camaro spacers. I run the ARP studs.

[HCI2000SS]

Thanks guys. Sounds like the the cheaper eBay ones will be just fine then at 3mm. The ZL1 Add-ons are like $100 with shipping for 4 spacers, and that just seems way overpriced for something like this. Also, will there be any issue with running hub bore adapters with the spacers? Stock hub bore is 66.9, and the wheel is 74.1.

[TheRealJA105]

No issues with the hub ring and spacer. I run them when I run my 19s.