Please confirm regarding spacer
 

I've tried looking the old posts regarding spacers, but still not very clear. Could you please verify if the set below can fit just fine into my box? I have 2004 boxster S with stock 17'' (not sure what offset these have).

Formula design 18'' silver
10.5 x 18 ET 42
8.5 x 18 ET 40

Will the above combo need spacer?

Also, I'm thinking to just put PS2 265/35 rear and 225/40 front.

Thanks for your help!

I do not have the particulars for your model of Boxster, but I can tell you from previous research into buying new rims for my 97 box that you will need spacers on the back of the rims you've specified above. The offsets in the back have to be in the 52mm range, so you'd need at least a 10mm spacer in the back. The front may work, but might rub the plastic wheel wells a little with or without spacers.

So if you're thinking of buying these rims, you're not done spending money if that's the basis of your question!

I do know that there are three kinds of spacers, hubcentric, wheelcentric and one that is a combination of both. From what I've learned here, you want a set of spacers that is both if possible to keep the car from making annoying vibrations at speed. Someone sells them online but I cannot remember who right now... it was mentioned here on this forum about a month or two ago.

Here's a thread that might help you a little with the hubcentric question:
http://986forum.com/forums/showthread.php?t=4595&highlight=hubcentric+spacers

I will try looking up the offsets for you, but in the mean time i wouldnt put a 265/35 on a 10.5" wheel....Its gonna look funny, i had a 265/35 on my 10" wheels and it looked too small for the wheel. I now have 285/30 and they look much better...

Thank you for the advice. I will try to go with the 285/30 instead of 265/35.

For spacers, I'll probably go with the techart ones. Hopefully the 18'' can fit and run without vibration.

Just got these quotes below from the wheel shop:

Techart Formula Design 18'' silver
8.5 x 18 ET 50 (50mm offset) 91,000 yen x 2 = 182,000 yen.
10.5 x 18 ET 42 (42mm offset) 101,000 yen x 2 = 202,000 yen.
Michelin PS2 tires
225/40 ZR 18 56,120 yen x 2 = 112,240 yen.
255/35 ZR 18 64,745 yen x 2 = 129,490 yen.
Other cost = 4,000 yen.
------------
Subtotal = 629,730 yen + tax
Total = 661,216 yen which is about USD$6000.

Does the amount sound right? Tires and wheels are a bit expensive I would think....

Also they 'strongly' recommended 255/35 eventhough I was pushing for 285/30. What do you think will happen if I go with 255/35?