What size tyres do I need?

[chibbard]

Hi all, I was running 17" RL7's on my 2000MY 4.5 Cerbera but now have 18" Spiders (Rear x 33) and (Front x 42). Could somebody please advise what tyre sizes I require in order to prevent rubbing. I was hoping somebody with the same setup could tell me what they are using as I have nothing to compare. Thanks in advance:-

[pmessling]

Fronts 225-35-18
Rears 255-35-18

Although you should have front wheels all round.
You may fine the rear spiders on the front will rub.

[pmessling]

That should have read

You may find the rears on the rears may rub as it should be fronts all round.

I tried rears and they did rub.

[chibbard]

Thanks for correcting that. I was wondering what you actually meant. I'll get tyres on them and see how I get on. Thanks for the reply!!

[Incognegro]

Hey Col you finally got round to getting your Spiders... Well played mate. Paul has got it right for you. As you are aware TVR never got everything spot on in that Cerbs should have the same offset wheels all round (The fronts are 8wide but the rears are 9) and would rub so even the fronts needed lock stops on the Cerb etc however some Cerbs (Like mine) were made to take the Tuscan offsets for some reason ???

You may need to play but the tyre info was correct

Goodluck mate

[chibbard]

So as it sounds like the rears may rub, how about if I ran a lower profile like 30's rather than 35's. Has anybody else done this instead? Also, which brands are recommended (I'd rather grip over long life). Thanks in advance !!

[gruffalo]

Goodyear Egale F1 Asymmetric get very good reviews.

I would think very carefully about a 30 profile tyre, the 35 profile tyres have quite an adverse effect on the handling of the Cerbera.

[chibbard]

gruffalo said:

Goodyear Egale F1 Asymmetric get very good reviews.

I would think very carefully about a 30 profile tyre, the 35 profile tyres have quite an adverse effect on the handling of the Cerbera.

So are you saying a 30 profile would be better? As that's how I read this? Or do you mean a 30 profile tyre would have an adverse effect

[FarmyardPants]

A touch of extra -ve camber at the rear can avoid rubbing if you have 33 offsets. I run 225/40 on the front with the 42 offset spiders and they are ok and protect the rims better and give a better ride. They sometimes rub a bit on full lock depending on brand. I use Pirelli p zeros at the front and Bridgestone potenza re040 255/35 rears (33 offset) and no rubbing at the back. The Bridgestones have pretty good grip in all weather conditions and last an amazingly long time considering the grief I give them

[chibbard]

Thanks for that info. That's good to know. I was considering Pirelli or Michelin to be honest.

[gruffalo]

chibbard said:

So are you saying a 30 profile would be better? As that's how I read this? Or do you mean a 30 profile tyre would have an adverse effect

No the opposite, the Cerbera rides beautifully on a 17" wheel with a 40 profile tyre, noticeably less well on an 18" wheel with a 35 profile tyre.

It was never engineered for 18 inch wheels, 16 and 17 inch yes but 18 no.

Think of it this way, the Cerb is a good handling car so is the latest 911, would you buy a new 911 and compromise it by fitting ill fitting wheels or would you run it on sizes it was designed for?