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Guys,

Am looking to replace the wheels on the car I bought yesterday. The wheels are in really poor shape but do have 4 brand new tyres on.

With that in mind, I was planning to buy a new set of 17’s as it seems a little crazy to me to buy 18’s and another 4 new tyres.

The wheels I’ve seen are;
Will they fit OK?

Thanks in advance

WBCZ4 wrote: ↑Sun Mar 24, 2024 9:44 pm Guys,

Am looking to replace the wheels on the car I bought yesterday. The wheels are in really poor shape but do have 4 brand new tyres on.

With that in mind, I was planning to buy a new set of 17’s as it seems a little crazy to me to buy 18’s and another 4 new tyres.

The wheels I’ve seen are;

IMG_1212.jpeg

Will they fit OK?

Thanks in advance

Assuming you mean you want a set of 17’s and change the tyres over, as there is nothing crazy about running 18’s on these cars. Those wheels will fit (assuming the CB is OK). They are narrower than your existing “daisies” but have a slightly more aggressive offset, so will sit about the same in the wheel arches. For precise advice, checkout www.willtheyfit.com.

Yes, apologies. I absolutely meant buying 17’s to reuse the new tyres I have at the moment. I’d prefer 18’s but seems like an unnecessary expense buying new tyres also.

Could you please explain what you mean by ‘more aggressive’?

Will that affect the ride?

Tyres I have are 225/45/17’s.

Thanks again

They'll fit, although I'd personally look for wider wheels if possible. Wider wheels = more grip even with the same size tire, and I wouldn't suggest to go under stock width unless you want a more playful car. The max wheel width you can run on 225s is 8.5 inches. I think 225s on 7.5 inch wheel will work, but it will be a "looser" fit and look meatier.

As for aggressive, Zedebee refers to the offset (etXX value giving distance from wheel hub to center of wheel) as closer to zero than stock (stock is et50 or something while these are et43). Also every .5 inch change in wheel width equals to about 5mm offset change. Eg. 7.5 inch wheels et43 ≈ 8 inch et48.

The optimal offset/width combo you can run on our cars to get the wheels in line with the fender (not inside) on stock suspension is 8.5 et35 in the front and 9.5 et38 in the rear.

For early models at least, the 2.2/2.5 was offered as standard with the style 104 “star spoke” alloys which are 16” x 7.5 et47.
The 3.0 was offered as standard with style 103 “daisy” (which you have) which are 17” x 8.0 et47.

So you can run 7.5”, but I doubt it’s recommended for the 3.0 unless you like lighting up the rear wheels. Interestingly the first Toyota GT86 (which I had) had very narrow wheels and Prius tyres, exactly so that you could slide the back end around.

Most Z4s got upgraded at the factory to 18”, with style 107, 108 and 135 (MV2) being the most popular. All these had 8” front with an offset of et47 and 8.5” rear wheels with an offset of et50.

All Z4s came to market with Pirelli run flats, as far as I know. The biggest difference you can make to ride and handling without messing with the suspension is ditching the run flats in favour of a decent non-run flat tyre, e.g. Goodyear Eagle or Michelin Pilot. Even mid-range tyres would be an improvement.

Generally speaking:
- smaller diameter wheels = more sidewall = more comfort
- wider tyres = more grip = more/less fun depending on your driving style
- wider tyres = possibly more road noise
- changed offset from standard, particularly at the front = can affect the steering geometry
- larger diameter wheels = often look better
- decreasing the offset, particularly at the rear (or using spacers) = look better

Thanks Guys, really appreciated.

Wheels are probably the most confusing thing I've considered on a car!

The tyres on the battered wheels currently are Goodyear Eagles, all are about 2 weeks old hence the reluctance to ditch them.

I'll keep my eyes open for a set of wheels I like that would be a straight swap. Would prefer 18's but figure, for now, my theory around sticking to 17's makes sense.