Plus 2 Tyres

[alanb]

Hi all,

I'd appreciate your thoughts on this.

+2S 130/5, 1973. Recent acquisition.

I've searched the archives but nothing definitive on the best or appropriate items to use, as far as I can see.

Currently fitted with very hard / perished Goodyear 165SR13s. Correct size replacements such as Dunlop Aquajet or Michelin XAS are available but at around ?180-200 each. http://www.longstonetyres.co.uk/search

Online research (including this forum) suggests that these are 82 profile.

Modern 165/80R13s are widely available for around ?50-70, fitted - examples here:
http://www.blackcircles.com/order/tyres ... 13&speed=S

My calculations say that diameters are as follows:
165SR13 are 23.653 inches
165/80 R13 are 23.394 inches or 98.9% of the current items.

Maths Summary: (for those currently fitted; from here: http://www.blackcircles.com/general/tyr ... calculator )
- Multiply a tyre?s width by the aspect ratio to get aspect height (165 x 0.82 = 135.30)
- Convert into inches (135.30/25.4 = 5.327)
- Double the aspect height (5.327x 2 = 10.653)
- Add inside diameter of tyre (10.653 + 13 = 23.653)

So 1.1% difference sounds OK in terms of speedo, just 0.257" = 6.5mm smaller diameter or 3.25mm lower ride height.

Comments, info on what tyres you currently use, etc. would be most welcome.

Thanks,

Alan

[Peter +2]

The dilemma we are all facing is that the Michelin XAS just look so right on all Elan variants.

It's just the eyewatering cost!

Sorry that I can't be helpful with your question.

Peter

[mbell]

So 1.1% difference sounds OK in terms of speedo, just 0.257" = 6.5mm smaller diameter or 3.25mm lower ride

I'd just select one of the many good 165/80r13 options you have in the UK if you just want to drive the car, plenty of threads on here with recommendations. 3.25mm difference is the difference between a new tire and have warn one, so I wouldn't class it as significant.

I am having to run 175/70r13 on mine as 165/80r13 are pretty much not available here now apart from the XAS. This is more noticeable difference but only really an issue if you want to cruise at high speed for long distances.

If you not sure about your calcs there are plenty of online ones you can use to confirm your maths.

[PhilatHooton]

I posted a similar question at the end of December -see " ongoing Plus 2 tyre conundrum"

I will probably go for some Kumho 165/80 13 for what its worth.

Iif you want to know everything about tyres read this website. It also has calculators to show the effects of different sizes.

http://www.carbibles.com/tyre_bible.html


Cheers

[alanb]

Thanks for replies. Sounds like 165/80 R13 is the way to go.

Phil - search doesn't find 'ongoing Plus 2 tyre conundrum'.

I can't find any tyre calculators that automatically work out diameter if you don't have the aspect ratio (ar). Hence my attempt at maths, based on an assumed ar of 82 for my current tyres.

Thanks again,

Alan

[PhilatHooton]

Alan


Forums.... then Plus 2 Forum discussions.

My post is on page 2.

The tyre calculator from the "bible" is on the last page and your calculations are correct.

Cheers

[alanb]

Thanks Phil, found it. Much appreciated.

Cheers,

Alan

[rgh0]

If you have a 5 speed and want good grip for hard road driving then the modern 175 or 185 / 60 x 13 profile tyres ( Yoko Dunlop, Avon, etc) are a real option for road use and a bit cheaper than XAS - FF and better grip with similar life IMHO and what I use on my road Plus 2S 130/5.

cheers
Rohan

[alanb]

Thanks Rohan - yes, I have a 130/5. Not currently driven fast due to the lack of grip from the old tyres!
Alan