18" or 19"; rim width?; TPMS sending units

[jefla]

I've an '07 S with standard 18" S rims ("8x"18 w/ 57mm offset in front; 9x18 w/ 43 offset in rear). No PASM; Conti SportContact tires. I'm toying with switching to "19 rims.

I read on one of the boards that to cars w/ "19 wheels should also have PASM, so switching to 19 is not advised unless the car has PASM. Now I can't find the posting and am wondering about this. Setting appearance aside, should I put "19 inch rims on my car? I expect a redution in comfort and that the 19s will be less capable of handling road hazards. Will they be a lot less comfortable? Handling that much better?

I'm confused by tire and rim width issues. According to Porsche's Tequipment accessories brochure, Porsche sells three different rear rim widths all mounted with the same tread width tires. These include: "10x"19 rims w/ 265/35 tires (Carrera Sport rims); 9.5x19 w/ 265/35 (SportDesign and others); and 9x18 w/ 265/40 (Boxster S). I assume the combination w/ wider rims but the same tire width produces less sidewall flex, meaning better handling but harsher ride. Also, curbs lurk everywhere where I live and drive (Washington DC), and I suspect a wider rim w/ the same size tire is much more exposed to curb hits. Please comment on this.

Finally, can I easily transfer the tire pressure sending units from my existing rims to new rims that may not have this feature?

Regards,

[husker boxster]

My LE came with 19s and I run 18s as my winter tires, so hopefully I can shed some light on your issues.

First, let me start with your last question. It depends. If you aren't planning to use your 18s again, then you can transfer them. If you plan to reuse your 18s then no. The only way you could transfer the monitors is to unmount your tires to do the transfer. Not economical and not good for your tires if you do this more than once. If you're going to sell your 18s, they won't be worth substantially less because they don't have the monitors.

My LE did not come with PASM, so I'm not sure why it would be a requirement when equipped with 19s. The widths on my 19s are 8" frt and 9.5" rear. If you put 19" Contis on, you'll probably not notice much difference in performance or ride between the 2 sizes. Neb has never been accused of having billiard table smooth roads and I've never had a problem with bent rims. If you hit a hole big enough to bend a 19, chances are it would bend an 18 too.

Should you put 19s on your Box? Absolutely, they look good on a 987S. Others may talk about extra weight and extra unsprung weight, but it won't be that much of a factor in every day driving. Do it.

[Perfectlap]

Anyone tried these offsets on an 18" wheel?
F 52MM
R 58MM

I'm considering a set

[jmatta]

Fronts would fit, rears would require at least a 10mm spacer.