I have decided to buy new tyres.

 

The tyre sidewall markings are as follows:

 

Front: 235/45/R17

Rear: 255/40/R17

 

My question is, why is the front aspect ratio (45) bigger than the rear aspect ratio (40)? Should this be the case?

 

At the moment they are all Bridgestone Blizzak winter tyres which came with the car. They are fine in the dry but are darn right dangerous in the wet. They aquaplane really easily. Also they have a maximum speed rating of 99 mph

 

Toyo Proxes seem to be the number one choice. MyTyres.co.uk have quoted £335 for 4 tyres. Does anyone know of anyone cheaper?

http://www.mytyres.co.uk/start.html

 

Try this site. They also show reports on tyres.

 

Fairly quick delivery but remember that you have to add the price of balacing, fitting etc to the price.

 

Darrell

 

Dow should have read the bottom of your post.

 

Would suggest that they are cheap but don't go for the cheapst tyres get the highest rating and have a look at the customer reports on the tyres etc.

 

Darrell

I have decided to buy new tyres.

 

 

 

My question is, why is the front aspect ratio (45) bigger than the rear aspect ratio (40)? Should this be the case?

 

 

because they are wider, they need a lower profile (which is a %age of the width) to maintain the same rolling radius ;)

because they are wider, they need a lower profile (which is a %age of the width) to maintain the same rolling radius ;)

i still cant get my head around this point aswell after all these years,how can the width of radius affect the overall height :confused: ,next time i get new tires ime not going to be bullied by height x width x colour x make =whatever sums and gunna get somthing that looks right as in the front looking the same as the rear :rofl: :rofl:

 

this is my opinion,it dont mean its right thou :D

because they are wider, they need a lower profile (which is a %age of the width) to maintain the same rolling radius ;)

 

Thanks bud.

 

I rang Falken tyres today and they cleared this up. It is because they are wider :)

 

I have ordered 4 Falken 452's. Came to £315 included P&P, which is about £30 cheaper than mytyres.co.uk

 

Should be here 2moz :)

£30 cheaper direct from falken? sounds good whats their number bud?

Next week i am ordering Falken 451's for the rear to complement the same on the front. I have 245's all round which is a bit odd. 265's on the rear would have been better. A lot of people think 245's on the front is too wide and can cause understeer, tramlining. But i have not noticed the car go sort of straight on from a hard turn yet. Wet road excluding :wack:

Thanks bud.

 

I rang Falken tyres today and they cleared this up. It is because they are wider :)

 

I have ordered 4 Falken 452's. Came to £315 included P&P, which is about £30 cheaper than mytyres.co.uk

 

Should be here 2moz :)

I rang Falken tyres today and they cleared this up. It is because they are wider

 

 

is that the anwser :confused:

Don't forget tyre pressures, I've found 28 p.s.i. all round on 235 - 255s is a good ride and doesn't appear to affect tyre wear.

Next week i am ordering Falken 451's for the rear to complement the same on the front. I have 245's all round which is a bit odd. 265's on the rear would have been better. A lot of people think 245's on the front is too wide and can cause understeer, tramlining. But i have not noticed the car go sort of straight on from a hard turn yet. Wet road excluding :wack:

Wider fronts would reduce understeer rather than increase it.

But I agree, I have 245 fronts (and 265 rears), and very happy with them. No tramlining, no negative affects on steering...and they are 19" with no rubbing.

 

the Falken 451 have been superceeded by the 452's now.

Don't forget tyre pressures, I've found 28 p.s.i. all round on 235 - 255s is a good ride and doesn't appear to affect tyre wear.

 

28 psi is much lower than stock, and you need more pressure on the rear than on the front.

 

34psi front, and 36psi rear is standard.

£30 cheaper direct from falken? sounds good whats their number bud?

 

http://www.falkentyres.co.uk

 

By Telephone: 0845 260 9003

By Fax: 0845 260 9004

By Email: sales@falkentyres.co.uk

Thanks

I rang Falken tyres today and they cleared this up. It is because they are wider

 

 

is that the anwser :confused:

 

Yes, he said the tyre profile is % of the tyres width. It didnt help much as it still went over my head but im happy that the tyre sizes are correct.

It's simple:

 

235/45x17 = 235x45% = 105.75 side wall.

 

255/40x17 = 255x40% = 102.00 side wall.

 

If you had 235/40's on the front the side wall would be 94.00 (too small) :)