195/70/14 HR Tyres

[milothedog]

Good question Julian,

I would hazard a guess that it's a combination of lack of understanding, what looks right on the car, availability and so on. A general rule of thumb is for every 10% you drop the profile you go 2 sizes wider hence why 205's are fitted buy some which is only fractionally different to the original rolling radius. if you do this on the calculator then you will see that you end up only being 0.7mph out on the speedo.

Ian.

As well as Carbibles have a look at http://www.autoshop101.com/

[Westfaling]

Anything wrong with Goodyear Duragrips? I think they're available in the UK. There is an asymmetric tread pattern option down here but not sure if you can get it in Blighty.
Nick

[chopperman]

Last year I bought 185/70HR14 Avons from Watling Tyres at £43.95 plus VAT. I had to order them but they only took 24 hours to arrive.
Keith

[stag-phil]

Correct me if I am wrong but the original tyres fitted to the Stag were 185/14, which assumes an aspect ratio of 80, therefore the original tyre size is 185/80/14.

Assuming that is correct, based on information obtained from ‘Car Bibles’, changing to different size tyres has the following effect on speedo readings:

If the tyres were replaced with 175/70/14 when the speedo reads 70mph the actual speed is 64.52mph

If the tyres were replaced with 185/70/14 when the speedo reads 70mph the actual speed is 66.02mph

If the tyres were replaced with 195/70/14 when the speedo reads 70mph the actual speed is 67.53mph

If the tyres were replaced with 205/70/14 when the speedo reads 70mph the actual speed is 69.03mph

That would seem to indicate that the best tyre size is 205/70/14.

The questions now are:

a) Are 205 tyres readily available?

b) Reasonably priced?

c) Fit the arches without any rubbing?

d) Any effect on the steering?

e) Any changes to the tracking required?

My car has been lowered so I would be interested to hear from anyone with a lowered car and 205 tyres.

Also, am I correct in thinking that the wider tyre will make the steering slightly heavier?

I was thinking of replacing the tyres with 195’s when the time comes but if the 205’s fit without any issues then that could be the way to go.

Phil

[73stagman]

according to my handbook the tyres were 175 HR14
I intend to change the wheels and tyres to 215/60/HR or VR 15. These are readilly available from Etyres who will come and fit them on my driveway.
This with the change of gearbox I have is the closest rolling diameter i can come up with to the original ratios to keep the speedo within the realms of decency.
HR is good for 130 MPH and the VR is good to 149 MPH.... plenty good enough either way.

[DJT]

according to my handbook the tyres were 175 HR14

This was the case during the last couple of year's production. The early handbooks also listed 185/70HR14, but according to some who were involved at factory level, none were actually fitted with those as OE.

Dave