8X16 Part# vs Dimensions Confusion - HELP!

[Wavey]

OK, before I get flamed for not doing my homework, be assured I've tried!

I'm trying to buy a pair of 8X16 Fuchs (911 fitment). The wheels have 2 different part numbers:

911 361 020 45

911 362 117 00

The seller says, and the pictures confirm, that the wheels appear to be identical. He has measured the backspacing and confirmed that they match - both have 122mm backspacing. Front spacing is also the same, and the petals appear to match visually.

Here's the problem: I've found conflicting information in the reference material I have, and neither agree with the actual wheel measurements.

This link: http://members.rennlist.com/911pcars/WheelWts.html
indicates that both numbers have 112mm backspacing, which doesn't match our measurements.

This link: http://members.rennlist.com/1976c38/index.html
indicates that the first number has a 120mm backspace, which is close enough to our measurement, but doesn't list the second number.

I'm satisfied that the pair of wheels in question have matching backspacing, will fit my Carrera, and appear to be the same visually. I believe one is an "early" wheel and one is a "late" wheel. But in that case I expected them to have different backspacing and to look different.

My question is, what is the difference between these 2 part numbers, if any?

[palle7688]

Fuchs PN: 911 362 117 00, is 8*16, 10,6 mm offset for 911.
Fuchs PN: 911 361 020 45 does not exist acc. to Bruce Andersons perf. handbook.
The closes I can get is 911 361 020 42 which's 8*15, 10,6 offset.
There no PN with 45 in the end.
All with 361 are "15 except 911 361 016 10 which are "14.
All with 362 are "16.
All with 020 are "15.
Are you sure both are "16, maybe 42 is misread as 45, in that case both will have the same 10,6 mm offset.

After written this I ran a check in PET, this is what came up:
911 361 020 45 Forged wheel 8J*16, 10,6 mm offset, dropped please use as replacement:
911 362 117 00 wheel-cast allumin. alloy, 8J*16, 10,6 mm offset.

I didn't know there where a cast fuchs wheel, I thought all where forged.
Apperently P. had Fuchs wheels made forged uptill '84 and cast after '84???????????????????????
Hopes this helps.
Any real experts out there?
Palle

[speeder]

Yes, PET refers to forged Fuchs as "cast" in some instances, don't ask me why. There were never any non-forged Fuchs 5-spoke 911 wheels.

It sounds like they are both the same wheel, If they are identical I wouldn't worry about it.

[KTL]

Dave,

The wheels are indeed the same dimensionally as far as offsets and width are concerned. But aesthetically/appearance-wise they are different.

My buddy Mark has a full set of .361 wheels in 7's and 8's, so i've personally seen the difference. I've also seen the difference in .361 and .362 16x6 wheels. I posted it here:

16x6 Fuchs Variations?

So as you can see, the difference is in the shape of the "petals" on the face and a few other details. I'm sure this could translate into actual strength differences and not just appearance, but I know nothing about stress analysis nor metallurgy.

[don911]

Kevin,

What differences did you see on 8x16 wheels? I've looked at the pixs of the 6x16 wheels and I'm not seeing those differences in the pedals on 8x16s. I have one 8x16 of each part number and if you can specify where the differences are on an 8x16 wheel, I can check out my wheels.

[KTL]

Here may be one of those weird Porsche issues.

Because .361 16x6 and 16x7 wheels definitely appear different than their .362 counterparts. I've seen it.

But Don says .361 and .362 16x8's look the same? WTF? Only wheel I haven't seen side by side is the 16x8.

[Wavey]

Thanks, Palle - the PET info you found goes a long way toward clarifying things, other than the obvious error Porsche made with the "cast" wording.

Kevin, I checked that link a few weeks ago, and I can see the difference in those wheels. Thanks very much for posting that, BTW. But these wheels, with 2 different p/ns, look exactly the same:



I wonder if, after production was begun on the substitute number, visual changes were made mid-production, but the number wasn't changed? Or maybe the differences were never there on 16X8s?

[don911]

I'll look at them again and take some measurements of the pedals. I took some pixs of the profile and didn't see a difference. If there are differences, the way they are painted may make it harder to see. I'll post some pixs tonight.

[KTL]

Dave,

Your picture would make me think those are .362 wheels with the "sharper" looking petals. But as you said, they are .361's!

Sorry to add to the confusion fellas. Probably was a wild assumption on my part.

[don911]

Kevin, the picture above is one of each p/n. 911 361 020 45 and p/n 911 362 117.

[KTL]

Duh. Of course. That's the whole point of this topic.

I'm an idiot. A free "slap upside Kevin's head" coupon is awarded to everyone in this topic..............

[Wavey]

If only my arms were longer...

So, anyway, now you see the dilema. I'm starting to think that the wheels must be identical, no matter what the part number. I'm not trying to be anal about it, just don't want to end up with 2 mismatched wheels (been down that road before).

However, another issue is that the actual measurements from these wheels don't match the charts we're all refering to.

Kevin, I'll PM you later - got a meeting right now.

[don911]

I think I found the differences. Not the outcome I wanted but better to know now.
The pedal side of each wheel seem to be pretty much the same. I measured some things on each wheel and all were the same. At least as near as I can tell with the black paint and measuring to a curve.

I say pretty much because there are differences.
1. The valve stem hole has a bevel on one wheel (362) and is a straight hole on the other wheel (361).
2. Where the spokes meet the hole for the center cap. The 361 wheel has a sharper curve at the interface than the 362. Visually it's hard to see but you can tell when you run your finger into the curve.

The difference on the inside of the wheel is in the shape or profile of the wheel looking in line with it. Hard to describe but easy to see. The shape from about the center to the inside lip is different. (in the pix, the inside of the wheel is the left side)

Mounted on a car you wouldn't be able to see the differences in the two wheels but they're there.

[tholyoak]

My take on the subject is that prior to 1985 the 8x16 wheel had a part number of 911 361 020 45, in 1985 that part was discontinued and the new part was 911 362 117 00, which as shown above has very slight differences visually but is dimensionally (width as offset) the same.

There are also 2 other 8x16 wheels that you can come across according to the Porsche parts book

Pre-85 911 361 020 99
Post-85 911 362 117 90

which are the unpainted versions of the previous two wheels (which are the black star versions) from the factory that I guess could then be painted any colour you wish.

Todd

[Bill Verburg]

Wavey, At my page http://members.rennlist.com/1976c38/index.html
the factory o/s #s are dead on, but since the factory never published the front or backspace #s I collected as many as I could from generous Pelicans and put them in one place . The #s you see there are the average of the #s that have been reported to me. The more data I get the more accurate those #s will become. Measure yours when you get them and it will be added to the pot.

FYI, all of the +10.6mm o/s fuchs will fit the same but there are minor differences that are mostly cosmetic.

Include part #s, weights, cosmetic differences that you notice and tires that fit and I will add that info as well.

[tchanson]

Another example:

Factory painted 8x16, 911.362.117:





Tim

[speeder]

Tim, That's a pretty wheel.

[nostatic]

I know that when I was looking at wheels, I found some 8s that didn't match the part number that had been given here (can't remember which one). I had Jeremy at TRE check, and at some point the part number changed (was superceded in the PET). So identical 16x8 wheels can have 2 different part numbers.

[Wavey]

Originally posted by Bill Verburg
Wavey, At my page http://members.rennlist.com/1976c38/index.html
the factory o/s #s are dead on, but since the factory never published the front or backspace #s I collected as many as I could from generous Pelicans and put them in one place . The #s you see there are the average of the #s that have been reported to me. The more data I get the more accurate those #s will become. Measure yours when you get them and it will be added to the pot.

FYI, all of the +10.6mm o/s fuchs will fit the same but there are minor differences that are mostly cosmetic.

Include part #s, weights, cosmetic differences that you notice and tires that fit and I will add that info as well.

Bill-

Thanks for the addition of the diagram to your page! Looks like your dimensions are correct as compared with the other link. When I actually get my hands on some wheels, I'll send you my dimensioons too!

[jpahemi]

Tim:
What's the colour code for your wheel?
Thanks,
J.P.