Jump to content
www.BoXa.net
Sign in to follow this  
strada84

987 Wheels on a 986 - Offsets

Recommended Posts

Hi guys,

I'm doing a bit of work on a 2001 986 Boxster S, which has a set of 987 Boxster S wheels fitted to it and it seems to be suffering from some rapid uneven tyre wear on the front (towards the inside edge).

I've been looking at the wheel offsets and tyre sizes and am looking for others' opinions on this.

The original wheel and tyre set up was as follows:

Front - 7.5J x ET50 - 225/40/18

Rear - 9J x ET52 - 265/35/18

The 987 wheels and tyre set up that is on there now is as follows:

Front - 8J x ET57 - 235/40/18

Rear - 9J x ET43 - 265/35/18

Now, initial observations are that the 235 are too wide for the front of the 986. 225 could be fitted. That would make the tyre sizes the same as on the original wheels, but the wheel offsets vary quite a lot. The front wheels will be sitting 13.4mm closer to the strut on the inside and 0.7mm further in on the outer edge, but the rears will be sitting 9mm further out on both sides. As I understand it, we could use spacers on the front to compensate, but as the rear sticks further out than original there's no way of compensating there. The rear tyres appear to be wearing nice and evenly. If we sorted the front out, would 0.9mm make a huge difference on the rear?

Are the 987 wheels never going to work successfully with a geometry set up, or should they be ok with spacers? If so, should we revert to 225/40/18 on the front? The 235 are very close to touching the arch liner on the inside and would touch on uneven ground on full lock in some circumstances. 

 

 

 

 

 

Share this post


Link to post
Share on other sites

225 as you've suggested, with a 7mm spacer would bring the fronts very close to 'original' fitment.

986 factory fitment with 18" 8j fronts and 10j rear is ET50 and ET47, respectively.

You obviously can't increase the rear offset, but you wouldn't be far off. Think they'd work fine with an alignment.

Share this post


Link to post
Share on other sites

Sounds pretty good to me and as expected. The 0.9mm difference on the rear is negligible.

Would a 7mm Spacer on the front definitely be enough? 

 

Share this post


Link to post
Share on other sites

The rears would be sitting out around 3mm than a factory ET47 10J 986 option, but isn't of any real consequence.

7mm spacers on the front give you an 'effective' offset of 50, which is stock  986 fitment for an 8J rim.

Share this post


Link to post
Share on other sites
On 5/19/2020 at 12:30 PM, K.I.T.T. said:

225 as you've suggested, with a 7mm spacer would bring the fronts very close to 'original' fitment.

986 factory fitment with 18" 8j fronts and 10j rear is ET50 and ET47, respectively.

You obviously can't increase the rear offset, but you wouldn't be far off. Think they'd work fine with an alignment.

The originals were 9J x ET52 Rear and 7.5J x ET50 Front (BBS Splits). I would be recommending 225s be fitted to the front for sure as its clear the 235s have been causing some other issues, so tyre size will be the same, but the 987 wheels are half an inch wider, aside from the offset difference. Just wanted to be double sure that a 7mm spacer would be the ideal. 

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
Sign in to follow this  

×
×
  • Create New...