This is the correct size required. I have sent you a message in relation to mine. I need to sell these, they have been boxed up since they were refurbished. Don't ever see me using them again. Shocking to admit but I have a full set of speedlines, replica cups and two sets of fuchs. Its a disease!
Fronts will be fine, however rears for a 993WB should be ET40 to achieve an OEM look and maybe a slightly lower figure to give a more stanced look.
The Rears you quote would require a 10mm spacer to look right as ET50's would sit 10mm further inside the arch. A good quality 10mm/15mm hubcentric spacer will give the desired look on an ET50 wheel. :thumb:
One option is go for BBS e28's as these are generally available in a greater array of offsets.
Regarding LM's there are a couple of options:
Option 1 - Stick with the ET50 and add a 10mm/15mm hubcentric spacer. Remember that the C2S WB was supplied from the factory on 17" Cup 2's and a 31mm rear spacer.
Option 2 - My personal favourite... Reverse mount the centres. This gives a greater dish and reduces the offset by 12-16mm, which is pretty much exactly where you need to be for the WB. Win Win...
Thanks Cableguy.. Option 2 probably better aesthetically but is there any issue with reverse mounting? I know loads of guys across the pond do it so I suppose we'd hear of any associated problems!?!
Lots of wheel builders are now reverse mounting. Ensure the mounting surfaces are clean and the fixings torqued up in sequence then there shouldn't be any issues. I can recommend a good wheel builder if you don't fancy doing it yourself.
I don't have LM's on the 993 but did have a set on an e39 M5 a few years ago.
I run 3 Piece Speedline Daytona's which have a more aggressive offset over OEM. Reverse mounting the Daytona's would be a little too aggressive unfortunately!
There are no adverse effects with reverse mounting the centers on LM's. You are probably aware of the LM's construction with the inner/outer barrel being a single piece, so its a very robust structure.
You will want to polish the lips as the standard LM finish looks a little odd when reverse mounting.
I would also highly recommend going with 8" fronts ET56 and 11" rears ET56 for an excellent fitment. As mentioned above, reversing results in a roughly 15mm reduction in ET.
Not without rolling the arches and maybe adding a little camber.
An OEM 10jx18" Speedline RS is ET65. I run a slightly more aggressive Speedline Daytona with an ET59 and my arches required a 25% roll to ensure no contact on full compression.
Sell your LM's & have a set of E88's built in the proper specs - the E88's are the 'correct' BBS wheel for your RS, especially when you have your clubsport bits on it.