Jeremy

For snow tire rims I picked up Borbet CBs (they look like Porsche Cups) for my 1986 951 w/ wheel adaptors. I was told that these were late offset, but I am hoping someone can confirm this. I believe a narrower rim is supposed to be better in the snow. Is anyone running 16 x 7.5s all around? Also, is there a way to determine the offset on a Borbet CB rim? Any additional thoughts are also appreciated. Thanks -

Jeremy

Luis de Prat

IIRC correctly, the Borbet Cup replicas were 17 inchers?

Jeremy

Luis -

Thanks for your response. They look like porsche cups, but are definitely 16 x 7.5 in size. I currently have 17" OEM Cups for my summer tires. I have googled around and my conclusion is that they were likely on another type of german car (BMW or VW are good candidates), even though I purchased them at Porsche swap meet in CT. Before I go through with the trouble of having the snow tires mounted, I thought I would query the forum. If you know anymore about Borbet rims - I appreciate your responses. Thanks -

Jeremy

Luis de Prat

OK, then it's a good thing they're 16" because I had read that the 17" version was substantially heavier than the stock Mille Miglia-made 17" Cup wheels.

As for offset, I believe they are indeed late offset. Generally it is embossed somewhere on the wheel. On an 86 951 you would need the spacers.

Track people like to use fronts and rears in the same width to get the most out of each set of tires. Not sure about winter handling, but at 7.5" I think it will depend on the kind of winter tire, more than anything.

Ken D

One issue to keep in mind is if they were fitted to a different make (BMW, VW, etc), they will likely have a different bolt pattern than what Porsche uses (5x130).

Jeremy

Ken -

I was concerned about this - but I was told that the Borbets actually came off of a Porsche by the PO(however, I think they may have originally been purchased to be put onto another make). I don't really doubt this information from him - he is a 911 owner and some of the incorrect comments seem based on his understanding of the 951 model, not a Porsche in general. If someone knows how to confirm other than measuring, please chime in -

Jeremy

rcatherton

I have the Borbet Cups on my 87 951 in 7.5 front and 9.0 back. The aftermarket Borbets are heavier then then the stock Porsche Cups. These wheels are no longer available and I have one on the front that is bent and I need a replacement. If anyone has a straight one for sale, please let me know.

rcatherton

Here is a picture of the wheels on my 87 Turbo.

Luis de Prat

Those are definitely 17 inchers...