9.5" Cup wheels, spacer question.

[hgo]

hello, I saw the same car. asked the owner the thickness of the spacer (i'm also runnning 9" ET55 spacer 15mm) he though it was more in the neighborhood of 45-50mm. no further ideas on this. but yesterday evening this also started me wondering. As I plan to have the 9.5" wheel ET68 spacer 21mm on my car. I made some drawings and can't get why it fitted under the arch but it was a very nice looking car and it fitted. so what is the clue, i think that you can't fix this with a lot of camber

 

[Atgani]

Teccy question for you all.

Whilst at Clastres last week I noticed a very tidy 964 RS Lwt fitted with the original (the race cars used them) & wider 9.5" & 8" x 17 aluminium Cup wheels.

As I understood it the 9.5" rear wheels require a 21mm spacer to ensure clearance between the rear face of the wheel and the oil lines.

Closer inspection of the wheels and spacers showed this particular car to be using spacers that were at least 40mm thick per side (if not thicker) I'm puzzled as to how the wheels fitted with such a large spacer and did not foul the wheelarches ?

The original 9" magnesium wheels have an ET of 55 and the fitment of a 15-18mm spacer brings them out pretty close to the arch edge in my experience.

The 9.5" aluminium wheel has an ET of 68 hence adding the recommended 21mm spacer makes it an effective ET of 47.

Using this to compare the two wheels specs : http://www.1010tires.com/wheeloffsetcalculator.asp

It says that the 9.5" wheel with a 21mm spacer will stick out 14mm further than the 9" magnesium wheel and have 2mm more clearance on the inner face, which all sounds about right.

Do the same using a 40mm spacer (as I saw on the car at Clastres) means the wheel has an effective ET of 28, and the wheel face sticks out 33mm compared with a stock 9" magnesium wheel AND has 21mm extra inner clearance ! ! This cannot be right ! !

The car was a black, British registered LHD example registration number B**PEA. Does anyone know the owner ? does he post on here ? If possible I'd like to discuss the above with him to clarify how the wider spacers have been accomodated.

Many thanks for your help in advance.

 

[Jamie Summers]

The owner does post on here every now and again as Barty964rst - also posts on 911uk and Rennlist. In fact have a look at the RS Fest thread, and you'll find him on there ! I shared your understanding of how those 9.5 inch cups worked with spacers, so am quite confused myself .......... For ref my RS running 9inch BBS race mags with 49 offset has 15mm spacers on and there is no way I could use a bigger spacer without fouling the arches or just relying on camber for clearance It's a mystery ........ Jamie

 

[Atgani]

Thanks guys. I wondered if the wheel pads had been machined, but you'd need to remove at least 20mm off the rear face, which wouldn't leave much shoulder material for the wheel nuts to bear on ! I'll pop over to RL and see if I can gain any further information.

 

[rs phil]

i have these rims on mine,21mm spacers at rear fit perfect,camber 2.3 deg,and toe in about 1mm,if my car had standard setup they would sit outside arch i use to have 15mm spacer with oe mags and they sit pretty similar maybe 1 or 2 mm further out with mags,also the tyres slightly bend in due to extra width if he had over 3 deg at rear that spacer probably would work??? seems like a lot though they look alot nicer than mags fitted extra width is lovely,if you want any photos of mine let me know

 

[Barty964rst]

Awaiting the 964RS Court decision on this matter. Statement I purchased the wheels from Speedservice in Netherlands as original Cup Cup 1 Alloys (as per Carrera Cup cars) 9.5 inch and 68 offset. I had the 21 wheels spacers fitted originally and there was a gap which several people commented on as looking a bit large/odd. So back they went and the garage tried various other spacers and camber and found with some serious camber dialled in, it was possible to fit 50mm, which certainly now fill the apertures nicely. The garage mentioned that the current fitment is the same as a Turbo 3.6 ( but that is another debate). I will look to see if there are some mm measurements on the spacers or I will measure and confirm back. http://www.flickr.com/photos/64231066@N02/5850270734/in/photostream photo shows Touring at the fore (standard) N-GT at the aft That M'lord is my defence for this henous crime of mixing oversize wheels, negative camber and bus spacers! [&o]

 

[Damen]

Guys In fact, I think the correct spacer for a 9.5" Cup wheel is 22mm not 21mm. That's what I've got with my Cup (I'm running 18" at the moment but also have a set of 8 and 9.5 x 17 Cup wheels). Just in case you need it, the part number for the 22mm spacer is 964 333 468 70. Damen

 

[Atgani]

ORIGINAL: rs phil i have these rims on mine,21mm spacers at rear fit perfect,camber 2.3 deg,and toe in about 1mm,if my car had standard setup they would sit outside arch i use to have 15mm spacer with oe mags and they sit pretty similar maybe 1 or 2 mm further out with mags,also the tyres slightly bend in due to extra width if he had over 3 deg at rear that spacer probably would work??? seems like a lot though they look alot nicer than mags fitted extra width is lovely,if you want any photos of mine let me know

Photos definitely required please Phil ! Barty, thankyou for your witness statement, I was shocked to see the spacers on the rear of your car, having done the calcs on the wheel offset calculator I was struggling to see how an extra 25mm of offset could be accomodated ! This is a wheely (groan) important matter and will be referred to the CPS for consideration . . . .

 

[rs phil]

oh no mine are wrong,come on 1mm[]

 

[rs phil]

my rims dont have 8 and 9.5 on outside of rim like mags etc,all part number on the back are correct for 91 cup car...?? they have been fully refurbed so its not that there is alot of paint

 

[Atgani]

Come on, show what pics you've got Phil ! Part Nos : Front 965 362 126 01 8 X 17 ET 52 Rear 965 362 128 05 9.5 X 17 ET 68

 

[rs phil]

would have to double check part no,i know they are et 52 and 68 for defo...are they diffferent variations in these? im sure i checked before i got mine that they were carrera cup versions

 

[Atgani]

Phil, the 9.5" & 8" Cup wheels I've seen have the rim width on the outside of the wheel next to the valve. I'm surprised that yours haven't ?

 

[Barty964rst]

ORIGINAL: Atgani Phil, the 9.5" & 8" Cup wheels I've seen have the rim width on the outside of the wheel next to the valve. I'm surprised that yours haven't ?

Mine have the sizes on the outside of the wheel! The offsets are 52 (F) and 68 (R). I have another set of Cup Cup 1's, so will check these when I next get to where they are stored. I will get to the garage tomorrow and check the accused!

 

[rs phil]

think they are 126.00 128.05 are these correct?

 

[rs phil]

http://www.944racing.de/wheelweights.php looks like i got the lighter version fronts[]

 

[Hacki]

21 mm was the original spacer, at least in 1990. Hacki

 

[hgo]

from this Porsche info partnumber sheet, the spacer is 21mm and has a VW number and was used in the past on 924 or 944 (this is why it's got a 477 number). at least this is how I see this... Hgo

 

[hgo]

Damen, I think the number you mentioned (964 333 468 70) is a steel washer with a thickness of 2.5mm, a hole of 12.2mm and an outside diameter of 22mm used somewhere in the rear suspension.

 

[Atgani]

ORIGINAL: hgo from this Porsche info partnumber sheet, the spacer is 21mm and has a VW number and was used in the past on 924 or 944 (this is why it's got a 477 number). at least this is how I see this... Hgo

I tried that part no at my local OPC a few weeks ago. IIRC they said it was NLA. Someone quoted another part number on Rennlist, they were still available but the price (each) was ridiculous. Better off going to Jasmine or dare I say it, the Porscheshop. Mind you if you asked them for a 21mm spacer they'd most likely send you two 10.5 mm items . . . . . . . . .