Unsprung weight Vs. Rolling diameter.

[HaydEn]

So with the up coming drags, I must choose some effective tyres.

At my disposal I have, 15's or 17's.

Now the problem being. The 15's with their 'more effective rolling diameter for n/a cars' need adapters, therefore weigh a fair bit. Which also adds weight to the car, but keeps it over the front axles for better traction.

The 17's are probably half the weight of the 15's but obviously have a larger rolling diameter, 'more suited to turbocharged vehicles.'

So, does anyone have any information on this topic. What's the better compromise, larger diameter tyres, or more Unsprung weight.

[VWindahouse]

Hey mate. The trick for want you're wanting to achieve is both reducing unsprung weight and reducing your overall rolling diameter and at the same time increase the width of the tyre for more traction. So a good starting place is with the original tyre size your car came with as your gearing is matched to that overall diameter. Then use this is a link to a tyre size calculator to see what tyre to run with the lighter 17" rims with the goal of minimising overall diameter or as close to stock and if possible with a wider footprint.

Tire Size Calculator - tire & wheel plus sizing

It's a bit of trial and error but worth it if you can find the right combo! Good luck.