Technical Who has experience with wheel spacers?

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Technical Who has experience with wheel spacers?

Stuartl

Maranellohouse.com
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Standard 1.9 JTD 3 door Still with standard 17" alloys, 35mm lower springs. I want them to bring the tyre out just short of the wing edge. I measured the distance and to me it would take 20mm on the rear and 10mm the front. Has any of you fitted spacers this size or even 16mm on the rear? if you had photos that would be the icing on the cake so I could see.

Thanks in advance, Stu
 
The vehicle manufacturer has spent a lot of time, money and expertise designing the car, including its suspension. Adding spacers will mess with that, and I doubt you or the spacer supplier has done much R&D. So you need to be careful, and expect undesirable results. You've already changed stuff with the lowering springs, which will now transfer more of each bump shock into the suspension mountings.

First, you need to be very sure that on full bump, the tyres will not contact any part of the bodywork, in any position from full lock left to right.
The standard setup is designed to put the centre of the wheel in line with the centre of the bearings. Usually spacers are used when wider wheels are fitted, to avoid fouling and to keep the centre of the wheel in line with the bearings. If the wheel centre is now offset, bearing wear will be greater than normal. by how much, is anyone's guess.

With wheels further out, the steering geometry is different, and may result in handling issues, or more rapid tyre wear. Suspension bushes may well wear quicker too.

With any spacers, you need longer bolts. The correct amount longer. You don't want the bolts poking through and fouling brakes, or not engaging enough, leading to wheel loss.
 
The vehicle manufacturer does indeed do all those things, and then finds the cheapest easiest solution using parts from the cheapest supplier. For instance, Stilo's come with 15", 16" and 17" wheels, which with different aspect ratio tyres give varied handling response, but they make them that way all the same.

In your case a set of spacers aren't really going to do too much damage, and in all honesty not much improvement either, so if that's what you want, go ahead and fit them.
 
If it was just for looks you could have packed it out with washers/nuts/spacers to see what it looked like, and then ordered the size you needed.
 
I've ordered 20mm for the rears so we'll see how far they bring the tyres out to the arch and then I'll know what I need to bring the fronts out the same.

I reckon it'll be about 20mm.... :whistle:

My advice with spacers is just to make sure you have pristine spigots.. 🤓 and that the wheel bolts are long enough.

Don't fit spacers that don't have a machined spigot (hub flange) to support the weight of the wheel.
A lot of cheap spacers are just a machined disc of alloy with holes drilled into it, which is great but it means the weight of the car becomes supported entirely by the wheel bolts, rather than the hub.

I would also only fit spacers that are bolted to the hub face but whose wheel bolt holes line up with the bolt holes in the hub. Apart from you get a touch more support, the spacer won't fall off every time you remove the wheel (and it's easier to align the spacer when you want to re-fit the wheel).

The new bolts should be the spacer's thickness longer than your existing bolts. Don't use your current bolts unless the spacer is 3mm or less thick.

The biggest issue with fouling is likely to be on the front, under load at full lock. The further out the wheel is, the bigger arc it makes as you turn the steering, so have a look at how close the outer shoulder of the tyre gets to the wheel arch liner as you (or someone else) turns the steering to full lock. If possible, stick your 20mm spacer on the front to test it while your chubby mate is sitting on top of the front slam panel, so you can see how close it gets.

The rear wheel has plenty of room around it and you'll see whether it sticks out close to or beyond the wheel arch lip. If it does, it will foul, so don't do it.

My preference, over wheel spacers would be to just fit wheels with a bigger offset (smaller ET number). You'll get the same effect but without all the additional ironmongery... although the fouling issue still needs to be checked.


Ralf S.
 
I reckon it'll be about 20mm.... :whistle:

My advice with spacers is just to make sure you have pristine spigots.. 🤓 and that the wheel bolts are long enough.

Don't fit spacers that don't have a machined spigot (hub flange) to support the weight of the wheel.
A lot of cheap spacers are just a machined disc of alloy with holes drilled into it, which is great but it means the weight of the car becomes supported entirely by the wheel bolts, rather than the hub.

I would also only fit spacers that are bolted to the hub face but whose wheel bolt holes line up with the bolt holes in the hub. Apart from you get a touch more support, the spacer won't fall off every time you remove the wheel (and it's easier to align the spacer when you want to re-fit the wheel).

The new bolts should be the spacer's thickness longer than your existing bolts. Don't use your current bolts unless the spacer is 3mm or less thick.

The biggest issue with fouling is likely to be on the front, under load at full lock. The further out the wheel is, the bigger arc it makes as you turn the steering, so have a look at how close the outer shoulder of the tyre gets to the wheel arch liner as you (or someone else) turns the steering to full lock. If possible, stick your 20mm spacer on the front to test it while your chubby mate is sitting on top of the front slam panel, so you can see how close it gets.

The rear wheel has plenty of room around it and you'll see whether it sticks out close to or beyond the wheel arch lip. If it does, it will foul, so don't do it.

My preference, over wheel spacers would be to just fit wheels with a bigger offset (smaller ET number). You'll get the same effect but without all the additional ironmongery... although the fouling issue still needs to be checked.


Ralf S.
Thanks Ralf. Did exactly that and fitted today.
 
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