Problem fitting wheel spacers

Just got round to fitting my 15mm Eibach spacers. Fitted the offside no problem look OK, went to the nearside and there is a gap between the wheel and spacer, front and rear, about 2-3mm.
After a bit of headscratching I remembered just after I bought the car, brand new with less than 50 miles on the clock, I had a bad day and came out of a roundabout and kerbed both n/s wheels, wasn’t too bad but I couldn’t live with it so I had two new wheels fitted.
Looks like that’s my problem.
What next…… grinding the studs is a no go. Will fitting 20mm spacers solve the problem. Or ditch the whole idea of spacers.

Mazda spent a lot of effort to set the cars up with the correct wheel geometry and you go and fit wheel spacers. That suggests to me that you have a reason to fit the spacers as Mazda got the geometry wrong or there would be no reason to fit the spacers.

Exactly what is wrong with the wheel geometry as standard to make the fitting of spacers a requirement.

Exactly where is the gap you report, is it between the wheel and the spacer or is between the hub and the spacer.

If you do not fit the spacer is there still a gap between the hub and the wheel.

Thank you for replying, without the spacers the wheels fit perfectly without any gaps, with the 2 n/s wheel spacers the gap is between the spacer and the wheel. I think the recesses in the replacement wheels must be different from the original, as the offside ones are fine. I still have the two original and when time permits I’ll measure them for a comparison. As for the reason for fitting spacers it’s purely for aesthetics, I like to see the wheels close to the edge of the arches.

I’m really struggling to understand this 2-3mm gap. Can you elaborate please.

Are you using OE wheels? I totally get the aesthetics point, but if you’re using aftermarket wheels with a different offset to OE ones that can be a good enough reason for spacers without necessarily upsetting suspension dynamics.

I think I understand your problem! Sounds like your replacement Mazda wheels have slightly more shallow recesses on the rear of the centre part of the wheel. It shouldn’t, but who knows. So you could fit 15mm on the front with the 2 original wheels, and fit 20mm on the rear with the newer wheels.

The 15mm spacers are a bit close with the stud length. Are the wheel nuts all the same?


Paddyman and plip1953 hope this answers your replies. THe replacement wheels are the same as the original, genuine Mazda, if you look at the back of the wheels there are four recesses that the studs still exposed after fitting the spacers will fit into, providing the spacers are thick enough.
The two wheels I took off have some damage. The new wheels I’m guessing don’t have the same amount of recess which means the studs are butting up against the back of the wheels. When I get the time I’ll do a comparison.
I’ve used the original nuts, and I like the idea of 20mm on the rear.
As for upsetting the suspension geometry it’s not likely but when it’s finally done it will be checked by my local Mazda dealer, I’ve just fitted spacers to my Mustang and it didn’t make any difference.

Would sound like the spigot is too long on the spacer for the new wheels, have you tried the other wheels on this side? Or that the pockets in the hub are not deep enough.
If you are desperate to fit them you can have 15mm dia holes drilled 3mm deep where the studs will sit. It won’t compromise the wheel.

Ok, so I now get what you’re saying, although it does indeed seem a bit odd that the recesses in the newer set of wheels are relatively shallower.

On a slightly different point, are you absolutely sure that the tyres won’t foul the arches when either 15mm or 20mm spacers are being used? Even with a 225 tyre on 17" +45 Rota wheels (Supercup standard non-OE wheel) I felt the need to cut away a section of the arch to prevent rubbing. And you’d effectively be running a 245/255 tyre!

NickD - not to keen on any mods to the wheels but I’ll give some thought to that. I am considering getting the two original wheels refurbished, that would solve the problem, the kerbing wasn’t too bad just at the time I was gutted being a brand new car.
Plip1953 - Absolutely no problem with fouling, have fitted the spacers all round at the moment just to see and there won’t be problem, just got to remember not to drive it.
Double checked the recesses on the original wheels and there is 15mm available. I need to remove the replacement wheels and check the recesses.
Not wanting to go against the rules, I am not a paid up member, don’t know why I’m on my fifth 5, must get it done anyway I will have two 15mm Eibach spacers to dispose of not run only fitted.

It’s quite common for wheels to change, it may be for many reasons, a new mould, different supplier, manufacturing reason, the list goes on.
The offset shouldn’t be any issue at all. The Rota Force wheel is 7.5" width so compared to your 225 (Super Cup tyres are 215 40) the OP’s standard tyres will 7.5mm inboard of yours.

Now sorted, at a price, After checking all 6 wheels the recesses varied between 13 and 15mm, if 20mm spacers are used then there would not be a problem. I decided that I would get the two damaged wheels, they only had very minor scrapes, refurbished, the company will re-powdercoat them one at a time using one to compare, they did an excellent job on my Mustang a couple of months back.

Yes, I could have fitted 20mm spacers all round and saved a good bit, but, having fitted the 15mm I think the front is just about right but the rear could take the 20mm.
I know when finally done the only person too see the difference will be me but……………
I’ll post a couple of pics of the car when finished.

15mm front / 20mm rear is the most common option people fit (myself included), initially i fitted 15mm all around only as I.L.Motorsport didn’t have any spacers instock at the time and i found a full set for £100, the rears i have since changed to 20mm and it sits better for it. I think the problem may well be that the recess depth was changed between ND1 and ND2, everyone i have spoken to with an ND1 has never had any issue, but i have seen an ND2 owner cut the original studs (not something i would ever do). There is a lot of negativity towards spacers, but the truth of the matter is especially when lowered, the wheels just don’t sit right on the car the way they are and the vast majority of aftermarket wheels are awful, so I don’t want to have to change the wheels to correct the issue.

Hmm, I kind of get you, but doesn’t the overall calculation when using the Rota ie taking into account offset, wheel width and tyre size, push things out something like 18mm - nominally 5mm tyre (225-215 divided by 2), 6mm on rim width (half the 0.5" increase) and 7mm for the different offset (+55 to +48?

Given that I experienced slight rear rubbing in that configuration, perhaps a 15mm spacer might just be possible, but not 20mm? There wasn’t an issue on the front so maybe 20mm is ok there.

My car is lowered 30mm on the Eibach Pro Kit, with 15mm spacers on the front and 20mm on the back I have zero issues. I know a lot of owners who run that configuration, some even lower on coilovers and still have no issues.

A standard MK3 wheel is 7" width and and 55 offset. The Rota is 45, in fact might even be 40 and 7.5" width. So the width adds 6mm and the offset change is at least 10mm if not 15. your 225, which is quite wide, is 20mm up on the standard tyre (theoretically) and so 10mm again. so the outside of your wheel is 10 for the tyre + 10 for the offset (maybe 15) + 6 for the rim. You can argue that the it is the section width not the wheel width that affects the width, however allowing the bead to sit 1/2" further out will add to the overall width. so total is 26mm (31) further out. Putting a 15mm spacer on a standard wheel and tyre just pushes that out the 15mm so there is an 11mm difference from your set up. The standard up size tyre of 215 and as used on the race cars and clears arches without issue takes 2.5mm off that so back to 8.5mm further inboard for the standard wheel and tyre.

You’re quite right, thank you. In the Supercup Regs the permissible Rotas are indeed +45 offset ( really don’t know where my suggestion of 48 came from lol). Also, I had in mind that a standard tyre was 205, not 215!

At least it’s not surprising that with that extra 26mm of “stick out” we encountered some rubbing lol