Thinking about spacers for summer wheels - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Perfectlap · 04-30-2009, 02:58 PM

I'm considering a set of 18" wheels that are 10" wide in the back. If I add spacers, is removing them when it comes time to replace my winter wheels a hassle? I assume I'll need longer wheel bolts, do those just tap out?
Complicating matters is that I'll probably be using 17" autocross wheels as I don't want to run with spacers in those conditions. hmm....
p.s.
what is the best range of size for spacers?

Burg Boxster · 04-30-2009, 03:24 PM

it depends on what kind of spacers and the size. IIRC, Porsche recommends 7mm max in front, 14 or 17mm max in rear. Under 17mm, you can easily go w/ the 'sandwich' style which attach to the rotor hat w/ just one philips head screw each. Then all you need are longer wheel bolts (45mm + whatever size spacer).

sandwich style:

If you go bigger, which you might need w/ 10" in rear depending on offset, you will need the bolt on style. These have either a second set of wheel bolts or have wheel studs (they'll give you the lug nuts or extra wheel bolts). You use your orig wheel bolts to hold the spacer to the hub and then mount the wheels to the spacer.

bolt on style:

For track purposes, I'm not sure what the ruling is if you can use the sandwich style or not. If not, they remove easily. I suspect you are fine w/ the bolt on style at the track though. Since you don't want to run w/ them at the track, you need to remove them and carry an extra set of wheel bolts w/ you (unless you get the bolt on kind).

Regardless, get hub centric spacers - period. Also, I recommend getting the same size spacers front & back. This will help eliminate some of the Boxster's understeer plus it makes it easy as all the wheel bolts will be the same length. Personally, I put 15mm all around and I know some have gone upto 17mm w/o any issues. 5mm which Porsche uses occasionally from the factory is not worth it IMHO. 17mm is only 2/3 an inch so it really depends on a) your needs and b) the look you want to achieve.

Good luck

timothy · 04-30-2009, 03:40 PM

I do that exact thing. For daily driving I have 18x10 rears with 10mm H&R spacers and longer wheel bolts. Come track day I remove the spacer and mount 17s using the original bolts. Taking off the spacer adds at most an extra 20 seconds to each wheel. Easy stuff.

jmatta · 04-30-2009, 03:54 PM

I think before you even begin considering spacers, you need to determine the offset of the 18 wheels you'll be mounting. With the offsets known, there are many here that can help you determine if spacers are necessary or desirable.

Perfectlap · 04-30-2009, 04:14 PM

50 mm front & 46 mm rear

Cloudsurfer · 04-30-2009, 04:38 PM

If you're running a 18x10 ET46 that is PERFECT. You do not want to space that any farther out. For a short time, I had 18x10 ET40 rears (which is what you would get with a 5mm spacer) and a 265 rear tire- there was barely any clearance to the fender. With an 18x10 ET50 (my BBS RSIIs are 18x10 ET50 and I run a 5mm factory spacer) there was barely enough clearance on the inside to slide a few sheets of paper through. So, 18x10 ET45 is about ideal, so if the wheels you're looking at are ET46 I would call it good.

I'm assuming you're looking at an 18x8 or 18x8.5 front, and ET50 is just about perfect there too.

Perfectlap · 04-30-2009, 04:45 PM

yup 18x8....

so the stock bolts should work?

Cloudsurfer · 04-30-2009, 04:57 PM

Assuming your wheels don't utilize a different shaped lug bolt, stock lugs should be fine.

jmatta · 05-01-2009, 04:46 AM

I agree with bmwm750; no spacers required and stock bolts.

Congratulations...

renzop · 05-01-2009, 06:35 AM

Another solution is to get rid of your wheel bolts entirely and replace them with wheel studs and open end nuts. The you can use sandwhich style spacers or not and have the same setup. Studs make changing tires much easier as you have something to hang the wheel on. Studs and nuts are also lighter than bolts and its are easier and cheaper to replace the nuts if you lose one. Check out rennline.com. That's where I got my set.

Perfectlap · 05-01-2009, 01:41 PM

Interesting. I always thought a 10" in the back required some modification not just "plug and play" so to speak.

I'll check out those wheel studs.

p.s.
I think center locking wheels will be the next big thing on sports car wheels.

husker boxster · 05-01-2009, 05:41 PM

The modification comes into play with the e-brake cable. You'll have to pin it out of the way, which is easier said than done. The suspension arm never holds the zip tie for long - it just slides down the arm and the cable moves back to its rightful place. Never did figure out a good way to do this on my 01S.

Also, no wheel weights on the inside rim of the wheel - they'll clip the suspension arm. Have to use the glue on kind inside the rim.

jmatta · 05-01-2009, 07:08 PM

As far as the e-brake cable; yes, you do need to tie it back. I found a package of wide, flat cable ties and installed three inline on each side. So far, no problem or movement. I think the key is pull them tight, but not over tight. I'd had several break, until I found just the right looseness; and they don't slide down either.

FWIW, I run 18X8 et50 front and 18X10 et47 rear.