My aim with the Coupe has always been to strive for something that allowed for a little personal stylistic expression, but looked OEM+; something that someone who wasn’t so intimately acquainted with all things Z4 might think was purely the product of BMW themselves.
So when I swopped onto 19” wheels, despite loving them, and having absolutely no rubbing issues on the Eibachs with 265 profile tyres, I started to obsess a little that at ET33 and 9.5J wide, they looked perhaps just a little too wide at the rear to be a convincing factory product. Any wider, and I would certainly be in Carlos Fandango territory!
So what to do?
I wondered about looking into taking off some metal from of the mounting face of the wheel to increase the inset by a few millimetres, but I was concerned that doing so might affect the structural integrity of the wheel and so discounted it.
It was then that I thought about extending the arches in some way, and remembered that cars like the Mercedes SLK have extension ‘spats’, which are there to meet some obscure EU directive regarding the amount of tyre that can extend beyond the wheelarch line. Looking into it further, it was clear that this was an OEM solution used by other manufacturers – Audi for instance used them on the Mk1 TT Sport to keep its wider track legal.
A definite possibility then.
At a recent local car show, I had the opportunity to look at the ones fitted to the SLK.
These would probably fit, but I’m not that hot on the looks and despite (or perhaps because of) being painted body colour, they don’t look that integrated.
Also at the same show, was an XK8-RS, which used the same sort of idea, but to my eyes were better designed and in plain black, were suitably low key. Importantly the arch profile looked very similar to the Z4.
At just over £20 a side, I thought I’d take a punt and so armed with some 3M double sided tape, spring clips (not used eventually) and a Stanley knife, I set to work.
The idea behind the two 'tabs' is that when fitted, they fold over the metal lip of the arch and prevent the spring clips from contacting the metalwork and stop the risk of starting corrosion. The lower part of the arch extension doesn't need these tabs, as the clips are fitted onto the plastic bumper. In the end, I decided against using the spring clips, mostly because I wasn't completely sure that I would get a tight fit to the arch and so just went with the 3M tape. The Stanley knife was used to remove the tabs and the little nodules that I presume serve some purpose by locating the extensions onto the Jag bumper. Starting at the lower edge of the Zed bumper, having previously cleaned the arch lip with an alcohol wipe, I carefully lined up the end of the arch extension and worked my way up.
Half an hour later, this was the result.
All in all, I'm pretty pleased with them and as they are only held on with tape, they can be easily removed to return to true OEM if required.