08" cayman S wheels on 986

[Mauiboxster]

I would like to know if these tires P235/40ZR/18, P265/40ZR/18 on 2008 Cayman S wheels will fit on a 1999 Boxster?

I have searched the internet for a few hours and can not get an answer.

[Mauiboxster]

does nobody know if these wheels will fit on a boxster?

[Gary H]

The size of the wheels and the offset is the vital missing component here

[Mauiboxster]

Thanks for a reply

Size of the wheel are 18's. I am not sure what the offset is. They are factory Cayman S wheels from 2008

[Mauiboxster]

Here is a link to the set I am referring to. Some help would really be good.

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=280560643247&viewitem=&sspagename=STRK%3AMEWAX%3AIT

[Gougoushu]

The man with the answer is Maurice a/k/a "Schoir." One of the outstanding members of the online Boxster community.

Look for him on this board, renntech, and ppbb. Send him a PM. He put Cayman S wheels on a blue 986 like yours, and they look sharp indeed.

As I recall, he needed spacers, which corrects for othewise incompatible offset. After you see his work, you might decide to paint your brake calipers yellow, along with some other nice touches to the wheels that he's done.

Offset is basically a measurement of how far out the base of the lug bolts are from the middle of the wheel. [More exactly, it's from the insde of the wheel where the lugs go through, to the center plane of the middle of the wheel. ]

Not enough offset, and the inside of the wheels scrape on your brake calipers or the like; too much and the tires might bump the fenders. It's denoted as "ET," as in "ET-44," meaning a 44mm offset. It should be stated in the specs section in the final pages of your owners manual.

Also, you can ask ebay sellers a question. So ask one of the sellers of Cayman S style wheels what is needed to fit your Boxster.

[Gary H]

Without knowing the offset, I'd say you'll a 15mm to 18mm spacer at the rear and possibly a 7mm shim on the front, but you'd need the offsets to check for sure.

Also the tyres sizes are out: The optimum sizes for a 986 are 225/40/18 up front and 265/35's on the rear.

[VGM911]

If I recall correctly, the '99 Boxster was offered with 16" wheels standard, with 17" as an option. Whether the suspension is designed for 18" or 19" wheels, I don't know. I've read that there was a subsequent change in suspension to support larger wheel sizes, referenced below.

However, if you move to an 18" wheel on a '99 Boxster, be prepared for a bumpier ride.

Here's information from a recent Rennlist post written by a very well-informed '02 Boxster owner:

"Lastly, IIRC 19" wheels/tires are *not* supported by Porsche on the pre-2000 cars. Starting in 2000 the cars received some changes to the chassis/running gear attachment points that supported the 19" wheels/tires and the bigger loads these subjected the car to.

My 02 came with 17" wheels/tires and I've driven a Cayman S with 18" wheels and my Turbo has 18" wheels and frankly/honestly 18" wheels is as big as I'd care to go.

Sincerely,

Macster"


Hope everything works out for you.