[Guest]

excess73:
Either way it sounds like your tyres could do with being wider. I have the bog standard 15"x6" Speedlines and I run the 205 width tyres. So, just using the difference you could be running a 235/40/16 tyre at least on those 7.5" rims. This would only give a 0.6% difference in size too.

Incidentally I've found that to go from my size (205/50/15) up to a 16" albeit wider, an almost perfect match is a 225/40/16 tyre.

And that funny symbol apparently represents the shape of the mounting surface of where the tyre sits.

Excess, the 16's should be running on 45's

wrinx

 

[Guest]

Yes - those centres fit Speedline wheels - I tried one in my standard 155 Speedline (15" 8 holes and rivets) wheel and it was the same size.

Unfortunately (?) I now have Mille Miglia's on the beast and the centre caps theron those are about 1mm bigger than the alfa one - the badge fits bit it is slightly loose and rotates in the housing.

By fantastic coincidence, the Alfa badge is also just the right size so it fits inside the badge recess on TSW wheels like Hockenheim and Blade (types with the big nut and the circlip over the wheel centre).

On my old P4 I turned the TSW badge over, and Araldited the Alfa badge to the back. I had to cut the locating legs off obviously as the TSW badge is essentially a metal disc held in from behind with a circlip).

The legless badge is just the right width so that the nut-retaining circlip can still fit in its groove. If you know TSW's you'll know what I mean. Could have been made for it dudes.

Ralf S.

 

[Guest]

Hey Wrinx,
If I was too fit 215/45s on a 16" wheel, my total diameter would be around 14mm larger. This would make my speedo over 2% out and read slower than I am actually going.
Probably not crucial really. Something to consider when I'm looking for my own 16"ers...

 

[Guest]

Justin

I'm confused about this diameter business. The handbook sez 45/16 or 50/15.

Don't lke the idea of travellng faster than the speedo reading...........not the speeds I travel at!!!!

wrinx

 

[Guest]

I suspect this isn't just about speedo readings either. If you alter the circumference of you wheel/tyre combo, you will presumably also affect the gearing. i.e;

if you increase the diameter of you wheel/tyre (e.g. by putting larger rims on, but not using low-pro tyres), that will make all your gears higher - possibly detrimental to acceleration, but a higher potential top speed if the engine is strong enough. Similarly if you put smaller wheels on you will probably be able to accelerate from low speeds a bit quicker, but will have a lower top speed in each gear.

I may be wrong? Anyone care to shoot my theory down in flames?

 

[Guest]

A larger total wheel diameter does slow down acceleration. This is why if you increase your wheel size too much you need to wrap them in rubber bands, instead of tyres.

Marlon