Tyre profiles

[Belle427]

I’m going to fit some 16 inch imolas to the front and just wanted to check tyre sizes.
From reading the new size will be 205/45/16 to the front, is this ok?
Rears will be 225/50/16, I think that’s standard size.

[QBee]

205/50/16 front will be closer to what TVR intended.

The standard fit on 15/16 inch wheels gave about a 25mm difference in wheel & tyre diameter front to rear.
205/50/16 gives you 20mm difference in wheel & tyre diameter front to rear
205/45/16 gives you a 40mm difference in wheel & tyre diameter front to rear

To help you choose:

205 is the width in mm
45 is the aspect ratio - the height of the tyre wall is 45% of the width
16 is the diameter of the wheel in inches. x 25.4 gives you the diameter in mm = 406MM
There is one wheel diameter and two side wall heights in one overall wheel and tyre diameter.

So 205/45/16 is 406+(205*45%*2) = 591mm
205/50/16 is 406+(205*50%*2)=611mm
225/50/16 is 406+(225*50%*2)=631mm

The factory I believe fitted 205/55/15 to the fronts.
15 inches is 381mm
381+(205*55%*2)= 606mm

Edited by QBee on Wednesday 30th October 09:45

Edited by QBee on Wednesday 30th October 09:46

[QBee]

Don't get too worried about a 5mm difference in diameter.

Remember:
A new tyre has 8mm of tread.
A ditch finder has 2mm of tread
So the difference in diameter between a new tyre and a ditch finder is 12mm

[Monsterlime]

I just did this, and fitted 205/50/R16 to the front and 225/50/R16 to the rear, in Rainsports.



Had a good drive in it, and am quite happy with how she drives. Much better than the awful stuff on there from the previous owner.

[ianwayne]

The first 18 months or so of Chimaera production, the front tyres fitted at the factory were 205/60 x 15. They switched sizes when Z rated tyres became unavailable in this size; a similar thing happened to the choice of rear tyres.

I use this site for reference in calculating wheel and tyre options:

http://www.rimsntires.com/specspro.jsp

[Belle427]

Monsterlime said:

I just did this, and fitted 205/50/R16 to the front and 225/50/R16 to the rear, in Rainsports.



Had a good drive in it, and am quite happy with how she drives. Much better than the awful stuff on there from the previous owner.

Looks good, any suspension adjustments to compensate?

[QBee]

Belle427 said:

Looks good, any suspension adjustments to compensate?

No, you shouldn't need any adjustment as far as i am aware

[Sardonicus]

Monsterlime said:

I just did this, and fitted 205/50/R16 to the front and 225/50/R16 to the rear, in Rainsports.



Had a good drive in it, and am quite happy with how she drives. Much better than the awful stuff on there from the previous owner.

Good choice sizes and tyre brand choice spot on

[Monsterlime]

QBee said:

Belle427 said:

Looks good, any suspension adjustments to compensate?

No, you shouldn't need any adjustment as far as i am aware

Yup, I had to make no changes.

[Belle427]

Thanks to all.

[SILICONEKID 357HP]

205/50/16
235/45/17

Fills the arches nicely .