My model of MX-5 is: NC
My 2006 has standard Mazda 5 spoke alloys and for my sins I really like the look of tuner nuts.
As my car has somehow acquired mismatched lug nuts over the years in the hands of previous owners I thought I’d change to a brand new full matched set of steel tuner nuts.
However one of the tuner nut listings I’ve seen says they’re only suitable for aftermarket wheels and not stock wheels…
Why?
Is there really any issue with using aftermarket lug nuts with stock wheels?
Can be absolutely all manor of things down to the dimensions of the “tuner” nuts.
By the way, the cheap, hollow, Aluminium style nuts are prone to cracking.
I’ve never bought wheel nuts before, but I didn’t like the idea of alloy anyway - these are steel, but are they “cheap” ?
Personally, I would avoid them. Two reasons, the small diameter, means that the area of contact with the wheel is quite small. Therefore the clamping forces are concentrated over a much smaller surface of material. When alloy wheels first started to become popular there was much talk of wheels falling off. This was due to the material, the aluminium alloy, being far more plastic than the more common steel, creeping under load and the wheel nuts coming loose. That was solved by different wheel nut design utilising a far bigger contact area.
That said, there are no doubt 100’s of people that will say they have used this nut with no issue for millions of years, but the fact the nut is not recommended for the standard wheel would give a big clue. I suspect the clearance hole in the standard wheel is quite large, probably around 14.5mm and these are just 20mm dia. The standard wheel nut is at least 24mm, so you lose a lot of clamping area and as a result subject the area used to clamp on to much higher force for the same tightening torque and therefore risk plastic deformation.
Secondly, they are stainless steel, which is prone to galling, so risk thread damage over time.
Thank you, I’ll get a full set of normal nuts instead 
