Porsche wheels

[JasonG98]

Hi guys, iv got a set of Porsche twist rims 7x17 et55 fronts and rears are 8.5x17 et50. Iv seen there’s some other posts about them from years ago but I need some things clearing up. I’m planning on fitting 205/40 tyres on all round but my main question is what size adapters? The other posts iv seen, people have said they’re running 25, 30, 35mm adapters but it doesn’t state whether that’s at each wheel or overall track width? So if I put 20mm adapters on each wheel that’s an overall track width of 40mm. So will they fit on 20mm adapters with 205/40 tyres on them with out rubbing archers? Or should I look at 18, 15mm adapters?
Thanks Jason

[Maarten]

Polo is 5x100 Porsche is 5x130

[JasonG98]

Polo is 5x100 Porsche is 5x130

Yeah I know but the adapters go from 5x100 to 5x130 so I can fit the Porsche rims. I just wanted to double check the thickness of the adapter, obviously thicker the better as the wheel nuts screw into them.

[SRGTD]

Worth checking with your insurance company to make sure they’ll cover you / your car if you fit adapters. From what I’ve read on some forums, some insurance companies don’t like spacers so there’s a chance those companies wouldn’t like adapters either.

Also, IMHO a 205mm wide tyre is very narrow for an 8.5J alloy unless you’re going for the extreme stretched look (would a 205 width tyre even stretch enough and still be safe on an 8.5J alloy?). I personally wouldn’t fit a 205mm wide tyre to anything wider than a 7.5J wheel. The ideal tyre width for 8.5J alloys would be 235mm or 245mm; see below;

IMG_0120.jpeg (109.44 KiB) Viewed 2123 times

If you go wider than 205mm tyres;

• there’s an increased risk of tyre rubbing with an 8.5J wheel with adapters fitted, as the face of the wheel and outside wall of the tyres will poke out quite a bit further than the factory wheel / tyre set up.

• you’ll need to go lower profile than a 40 section tyre; if not, you’ll get a speedo reading error.

It’s worth using a calculator like the one at www.willtheyfit.com - input details of your new and existing wheel/tyre set up and it will calculate the important numbers for you (e.g. tuck, poke and speedo reading error). To avoid speedo reading errors, the overall rolling radius of your new and existing wheel / tyre set up need to be the same. Remember to add the thickness of the adapters to the calculator result for the amount of poke for the new wheel / tyre set up. Bear in mind that it’s illegal to run wheels and tyres on a car that extend beyond the wheel arches.

[PoloSDI]

That chart is over-simplified, as it doesn't include the tyre's aspect ratio.

Here's a useful chart, that's been extracted from a 2016 ETRTO manual.

All of the big car companies such as VW, and all of the big tyre companies such as Michelin, have to follow ETRTO's Rules.

ETRTO approved rim widths for passenger car tyres

80 Series
135/80 3.5-3.5-4.5
145/80 3.5-4.0-5.0
155/80 4.0-4.5-5.0
165/80 4.0-4.5-5.5
175/80 4.5-5.0-6.0
185/80 4.5-5.0-6.0
195/80 5.0-5.5-6.5

70 Series
135/70 3.5-4.0-4.5
145/70 3.5-4.5-5.0
155/70 4.0-4.5-5.0
165/70 4.0-5.0-5.5
175/70 4.5-5.0-6.0
185/70 4.5-5.5-6.0
195/70 5.0-6.0-6.5
205/70 5.0-6.0-7.0
215/70 5.5-6.5-7.0
225/70 6.0-6.5-7.5
235/70 6.0-7.0-8.0

65 Series
145/65 4.0-4.5-5.0
155/65 4.5-4.5-5.5
165/65 4.5-5.0-6.0
175/65 5.0-5.0-6.0
185/65 5.0-5.5-6.5
195/65 5.5-6.0-7.0
205/65 5.5-6.0-7.5
215/65 6.0-6.5-7.5
225/65 6.0-6.5-8.0
235/65 6.5-7.0-8.5
245/65 7.0-7.0-8.5
255/65 7.0-7.5-9.0

60 Series
155/60 4.5-4.5-5.5
165/60 4.5-5.0-6.0
175/60 5.0-5.0-6.0
185/60 5.0-5.5-6.5
195/60 5.5-6.0-7.0
205/60 5.5-6.0-7.5
215/60 6.0-6.5-7.5
225/60 6.0-6.5-8.0
235/60 6.5-7.0-8.5
245/60 7.0-7.0-8.5
255/60 7.0-7.5-9.0

55 Series
175/55 5.0-5.5-6.0
185/55 5.0-6.0-6.5
195/55 5.5-6.0-7.0
205/55 5.5-6.5-7.5
215/55 6.0-7.0-7.5
225/55 6.0-7.0-8.0
235/55 6.5-7.5-8.5
245/55 7.0-7.5-8.5
255/55 7.0-8.0-9.0

50 Series
175/50 5.0-5.5-6.0
185/50 5.0-6.0-6.5
195/50 5.5-6.0-7.0
205/50 5.5-6.5-7.5
215/50 6.0-7.0-7.5
225/50 6.0-7.0-8.0
235/50 6.5-7.5-8.5
245/50 7.0-7.5-8.5
255/50 7.0-8.0-9.0

45 Series
195/45 6.0-6.5-7.5
205/45 6.5-7.0-7.5
215/45 7.0-7.0-8.0
225/45 7.0-7.5-8.5
235/45 7.5-8.0-9.0
245/45 7.5-8.0-9.0
255/45 8.0-8.5-9.5

40 Series
195/40 6.5-7.0-7.5
205/40 7.0-7.5-8.0
215/40 7.0-7.5-8.5
225/40 7.5-8.0-9.0
235/40 8.0-8.5-9.5
245/40 8.0-8.5-9.5
255/40 8.5-9.0-10.0
265/40 9.0-9.5-10.5
275/40 9.0-9.5-11.0

35 Series
215/35 7.0-7.5-8.5
225/35 7.5-8.0-9.0
235/35 8.0-8.5-9.5
245/35 8.0-8.5-9.5
255/35 8.5-9.0-10.0
265/35 9.0-9.5-10.5
275/35 9.0-9.5-11.0

30 Series
245/30 8.0-8.5-9.0
255/30 8.5-9.0-9.5
265/30 9.0-9.5-10.0
275/30 9.0-9.5-10.0

https://btmauk.com/wp-content/uploads/2 ... d-Rims.pdf

[chewy]

I ran 20mm all round iirc sure they were 7.5 ET 53 and 9 ET 47 with 195/40 and 215/40.

Pictures will be on my build thread on here