alloy vs steel

I considered the same question when my alloys began losing air due to corrosion. (I eventually decide to strip and repaint my wheels)

As I understand it, steel wheels should be as strong if not stronger than an equivalent alloy wheel, plus they are much more resistant to cracking under impact.

On the question of weight, the Copen alloys are particularly heavy, somewhere in the region of 7kg.
The nearest alternative I could find were wheels from the Mini2, the steel versions of which are actually lighter than the copen alloys.
The Mini wheels are 15 inch, but with a width of 5.5 as opposed to the copen with 4.5. They have the same PCD of 4x100 and the same offset of 45.
There is a difference in the bore diameter with the mini wheel being slightly larger than the copen, some spigot rings would be needed for correct fitting.

The tyre size remains the same. In fact, according to their website, the bridgestone re040 165 50 r15 (copen standard tyre) is not specced for 4.5 width wheels, and would be better suited to the 5.5. The only change from going up to 5.5 width would be a very small increase in contact patch width.

When it comes to the slightly larger wheel, a 15 inch wheel with a width of 5.5 should fit comfortably within the copen wheel arches without danger of rubbing. Hopefully other members will be able to clarify this point.

All this information has been gathered from from the internet so I would be inclined to test any possible replacements for fit before making a purchase.

 

Possible steel-rim/tyre combinatons I have heard of:

5x14 (Offset 40)
6x14 (Offset 35)

both with 165/60R14 tyres.

That is a common combination on Copens in Germany for winter-tyres.

Andreas

 

Search online, some tyre retailers provide a conversion calculator so you can find out what combo has a minimal difference to as fitted.

In theory it will be the same if the circumference remains the same. But higher profile (thicker) tyres will give you a soft, more comfortable ride but create more roll so a less sporty ride. Under hard acceleration it will twist the tyre more than a low profile one so there is some loss there. But if you just tootle around at 30 mph everywhere there would probably not be an issue.

If you change the circumference significantly then the speedo will be out. Even though here in the UK it is out but 4/5 mph depending on the speed. I posted my speed differences.

You ask if it will be faster? If your circumference is reduced you may find it accelerates a bit quicker but you will be changing gear earlier and be cruising with a racing engine, i.e revs will be higher for a set speed in a set gear. And the turbo car is racing and noisy anyway!

Also smaller wheels in the wheel arch would look silly to me.

 

Put into perspective, thats about the same difference as going from a worn tyre at minimum tread depth to a brand new tyre.