the car came with 205/45 R 17 dunlop runflats which are quite bouncy/rough ride. I am thinking of switching to regular tires. what size and brand should I go for best ride and price combo? Is a 215/40 R17 a good size to use? or should I stick with the stock size?

 

and lots has already been posted. But if you run a 40 series, watch your tire pressures like a hawk. Some brands don't come in 205-45s, so lots depends on what tire you want and what your budget allows.

No matter what, you'll find the difference surprisingly wonderful!

Matt

 

thank you for the quick response. Is there an impact on the TPMS function when using a non-runflat tire for a 2006 S?

 

You only have FTM (flat tire monitor) not the TPMS system in the 06, it works with any sort of tire, though it may be obvious you have a flat before it responds with a real tire.

Personally, I put Goodyear Eagle F1 GS-D3's on ours.

 

you've got a wheel speed sensor based system, no sensors in the wheels. What it means is that the air pressure warning is done by seeing if the relative wheel rotation rates change. It's a nice system, but it's not that sensitive. Best bet is to keep checking your tire pressures weekly or so.

Matt

 

I have to agree with Matt on all of his response.
I switched from Pirellis Runflats to Goodyear tires and I have never been happier.
The ride is smoother, quieter and the tires last longer not to mention they look really sharp when you park with tires sticking out to one side.
Oh! Did I mention they were less than half the price of the runflats?!

 

but TireRack had a special on the Goodyear GS3D, 215-40 ZR 17 for $76 each... And a $50 rebate from goodyear to boot! Freakin awsome deal! A Perelli UHP tire was for sale at $60 each, no rebate, but with slightly lower tread wear rating.....

I got a set of the Goodyears even though I"ve still got some mileage left on my tires. Price was too good to pass up.

Matt

 

thank you. i am sold. the goodyear is on backorder at tirerack. so what is the difference between the stock 205/45 r17 and 5he 215/40 r17? which one is taller and/or wider? what is the impact on speedometer?

 

Depending on which Goodyear you go for they do come in OEM sizes 205/45/R17 but if you go with 215/40/R17 then you'll end up with a tire that is wider with a lower profile.
As previously stated "Watch your air pressure" if you go with a lower profile, otherwise you'll be replacing rims.
The MINI's speedo on my car is off by about 5 mph but if you go with the 215/40/R17 then you may only be off by 3 mph.

 

Yeah I run 225/45/17 and my speedo is off by 3 mph so definately watch that. And even with a 45 series tire I still managed to bend a rim...

 

Just ordered a set of the GS-3Ds... where is the rebate form, please?

In answer to the height question, the first number (e.g. 215) is the width of the tread in mm. The second number (e.g. 40) is the aspect ratio--the height of the sidewall as a percentage of the tread width. This is the height of the sidewall from the road to the rim, so difference must be doubled to get height difference between tires of different sizes.

To get the actual height in mm, multiply the first number by the second and divide by 100 (or move the decimal 2 places to the left).

If you want the mm translated to inches, divide it by 25.4...

215 x 40/100 = 86mm

205 x 45/100 = 92.25mm

Difference = 6.25mm = 0.25 inches

The 215/40 will be 1/2 inch lower than the 205/45

Hope this helps.

 

thx. there is a $100 discount at america tire this weekend in LA:
http://www.americastire.com/content/...100Coupon.html

so which one would give the better/softer ride: a 205/45 R17 or 215/40 R17?

 

The 215/40 is ~2% smaller diameter than the 205/45.
The higher aspect ratio will always give a softer ride, all else equal.