Rear tire size? 225/45 R17 or 255/40 R17 which one for comfort?

[CDNIcecube]

Hi all

I need your collective wisdom here....

I have a 1999 base and the current rear tires need replacing and they are 255/40 R17 tires (summer tires).

Yet I see on the tag in the frunk that it can also take 225/45 R17.

This is a weekend car my 60 year old body likes to take it easy over the summer: I don't race nor speed. I am not looking to change rim size either. I am looking for comfort. What size would be best? 225/45 R17 or 255/40 R17 tires for this type of driving in the summer?

Thank you!

Icecube

[997_986]

255/40 R17 is the only correct dimension.

[CDNIcecube]

Thanks!

I'll go with 255-40 but it is odd that the 225/45 R17 is clearly indicated on a Porsche sticker inside the Frunk (the one where the recommended tire pressure are recommended).

Cheers!

[mikefocke]

Tire rack agrees.

[JayG]

maybe 225's on the front

[husker boxster]

You don't mention what brand you're currently using. Brands make a huge difference in ride. Even within brands can matter too. For example, the Mich PS2 (amazed they still sell these) has a stiff ride while the Mich 4S does not. Look at the tire's characteristics (ride, wear, etc) on TireRack for tires that have a good ride.

[997_986]

Front 205/50 R17 with Rim 7x17 - 55
Rear 225/45 R 17 with Rim 8,5x17 - 50/48
or
255/40 R 17

if using original Porsche rims

I have the smaller rear dimension as winter tires and the wider ones in summer. There is no difference in ride quality.

[PLP]

Originally Posted by CDNIcecube

Hi all

I am looking for comfort. What size would be best? 225/45 R17 or 255/40 R17 tires for this type of driving in the summer?


Icecube

I doubt you would see any difference.

255/40 is 102 mm side wall height
225/45 is 101 mm side wall height

Maybe 225/50 would feel better, but then you are messing up with ABS/speed sensors due to different wheel height/rotational speed front vs back. Or you need to match front tires now.

I find Boxster to be more comfortable on bumpy road that some of the hatchbacks.

[lkchris]

Originally Posted by 997_986

255/40 R17 is the only correct dimension.

Not correct.

The 225 size is listed in my owners manual for Winter tires. I have Vredestein Winter tires in that size. These tires are/were listed in the N tire list from Porsche, but do not have N on sidewall.

The narrower tire would be the more comfortable ... less expensive, too.

[997_986]

Originally Posted by lkchris

Not correct.

The 225 size is listed in my owners manual for Winter tires. I have Vredestein Winter tires in that size. These tires are/were listed in the N tire list from Porsche, but do not have N on sidewall.

The narrower tire would be the more comfortable ... less expensive, too.

Yes, you are right, see my second post.I run the 225/45 as winter tires as well.