Another wheel question

[Case]

I'm considering purchasing a z3 coupe, and was wondering how I could go about achieving the rear wheel look of the z3m coupe. Besides the obvious answer of bying the z3m coupe :tsk: I searched, and searched so please don't yell. I thought originally I could just place the mcoupe wheels on, but after searching, I discovered that would not achieve the look (because of the mcoupes offset?). Could anyone advise as to what offset I would need and if spacers would be required to push the wheels out to fill up the wheel well like the mcoupe does? Or is it just not in the cards?

[Brent95M3]

I'm considering purchasing a z3 coupe, and was wondering how I could go about achieving the rear wheel look of the z3m coupe. Besides the obvious answer of bying the z3m coupe :tsk: I searched, and searched so please don't yell. I thought originally I could just place the mcoupe wheels on, but after searching, I discovered that would not achieve the look (because of the mcoupes offset?). Could anyone advise as to what offset I would need and if spacers would be required to push the wheels out to fill up the wheel well like the mcoupe does? Or is it just not in the cards?

The M Coupe wheels would stick out too far to begin with so spacers certainly aren't the solution. You could have the hub of the wheel ground down so it would fit on your car but that isn't the solution either due to safety concerns and wheel integrity. So you have a couple solutions to get that look. A. Buy 4 front M Coupe/Roadster wheels. This will sort of do it, but no deep dish rear wheel. B. Buy an aftermarket wheel with a big deep dish on the rear. You'll have to do some searching, but I know they make aftermarket wheels with a deep dish. Luckily you have a lot of used choices too since the E36 crowd uses the same offsets. Good luck. :thumbup:

[Case]

Thanks, Is it correct that the lower the offset i.e. 40 compared to 45 means that a 40 offset wheel would stick out further than a 45?

[Brent95M3]

Thanks, Is it correct that the lower the offset i.e. 40 compared to 45 means that a 40 offset wheel would stick out further than a 45?

Yup, and the M Coupes rear wheel offset is insanely low (forget the exact #). For your car you'll need an offset of 38-42. I have seen some nice aftermarket deep dish rims for the old E36 M3 come up for sale on occasion for reasonable prices (probably a comparable lip to the M Roadster wheel).

[TurnAround]

how I could go about achieving the rear wheel look of the z3m coupe. The look of the two car's rear wheels is nearly identical in it's stock form. Same wheel width and diameter and same tire sizing. And while the hub offsets are different, the outside edge of the rim(s) come to the same point in space in relation to the fender edges.

The only difference is that the M's spring set the car up just slightly lower. It varies from car to car. Everybody seems to report different measurements.

So.. is it the extra space between the top of the rear tire, and the fender edge that you're wanting to reduce on the Z3C? You can go with H&R springs for a more lowered look. Several have done this. Do a search for Andy Maddux's lowering project for an excellent example (and write up).

Z3C's have a little more negative camber than the M's. If you lower the Z3C, you'll achieve the look of the M (or even lower), but you will introduce yet more negative camber. Some guys like this. Others are concerned about tire wear. But, you can always swap the tires once in their lifespan to fight this problem.

I'd like to lower the back of my Z3C juuuust a little bit. The backs on these cars have 3/4" more gap / visible space than the fronts. There were three different rear spring rubber perch pad thickness used on these cars. 5mm, 10mm, and 15mm. If you get a car with the thicker perch pads, you can swap them out for 5mm pads to get a little drop. Also, the boys at TC Kline syspension say that you can just remove the perch pads all together. Although, I haven't run that one past the guys here yet, to see if it's ok to do.

You can also go with a TC Kline adjustable coilover shock kit, and fine tune the ride height. Lower it some.. like a stock MC, but not so much that you incur a bunch more negative camber.


I considered wheel spacers to create the illusion of filling up the wheel well more. In my humble opinion, after studying the problem... I've determined that spacers alone would not be enough. If / when I lower the rear slightly, I probably will go with spacers at that time. The combination of the two approaches should look wicked. There's some pictures on the RF Coupe board of Z3C's done this way. It looks awesome. 12mm spacers I believe. If I do it, I'll probably go with H&R spacers, because you get to keep using your OEM wheel bolts (other spacer systems like Rougue.. you end up with silver bolts, or silver nuts if using the stud system).

[fpa1974]

I'd like to lower the back of my Z3C juuuust a little bit. The backs on these cars have 3/4" more gap / visible space than the fronts. There were three different rear spring rubber perch pad thickness used on these cars. 5mm, 10mm, and 15mm. If you get a car with the thicker perch pads, you can swap them out for 5mm pads to get a little drop. Also, the boys at TC Kline syspension say that you can just remove the perch pads all together. Although, I haven't run that one past the guys here yet, to see if it's ok to do.


Just a slight correction here :) Unless the non M cars are different (which I doubt), the pads sizes for the rear are: 5, 7.5 and 10. Mine came with a 10mm pad from the factory. I now have a 5mm one (in addtion to the TCK setup mentioned above).

There is a problem with no pads with the TCK kit BTW. The height adjuster is aluminum, the car's control arm is steel. That is not a good combination for long term direct contact. TCK also suggests to run the springs without the height adjuster. The spring ID for the VVS springs will not perfectly match the notch on the control arm (they match the height adjuster). While that works the spring will move around ever so slightly, creating some very subdued noises that I chose not to have. I ended up going with the thinnest pad available, spring and height adjuster. Car is lower than stock by about 3/4 of an inch and has 0 extra noises. Plus the hadling as opposed to stock is just not comparable. Now the car behaves truly like a go kart.

Florian

[dwm]

Florian, I assume you put the height adjuster on the top like I did with my KW? Got a picture?

I wouldn't worry much about galvanic corrosion. I'm assuming the TCK height adjusters are hard anodized like their camber plates. As long as they're not grinding away at things by moving around, it shouldn't be any worse than the spring pads (which trap a lot of dirt and water).

[fpa1974]

Florian, I assume you put the height adjuster on the top like I did with my KW? Got a picture?

I wouldn't worry much about galvanic corrosion. I'm assuming the TCK height adjusters are hard anodized like their camber plates. As long as they're not grinding away at things by moving around, it shouldn't be any worse than the spring pads (which trap a lot of dirt and water).

I have the adjuster on the bottom (on the control arm on top of the 5mm pad). TCK tells you to put it there. But they mentioned to me it can be on the top too. If I put it on the top I would have the spring id problem I mentioned above since the spring would have to sit on the control arm (with or without pad) and the notch on the control arm is slighlty smaller, thus the slight movemement of the spring around and a bit of noises.

You are correct about the adjusters. They are anodized. To be honest I chose to play safe. The pad is only 5mm. I really do not care if my car sits 5mm higher when I feel better about things. I also would be concerned about noises in this case as well since I suspect the adjusters will slightly move a bit (not as bad as the springs but still).

I can snap a few pics next time around I am in the area which should be soon since I will have a fluids change day in the near future.

Florian