M491 Wheel Question

[tdw28210]

I should know this already, but I want to be sure. And I am away from my M491 so I cannot verify myself.

Question: I believe most of the earlier The M491's came from the factory with 7J and 8J wheels, (sporting a 944.xxx.xxx.xx part number) and factory wheel spacers.

In the later years, they came from the factory with actual turbo wheels (7's and 9's) with a 911.362.XXX part numbers. Yes/No? Thanks.

[Bill Verburg]

Originally Posted by tdw28210

I should know this already, but I want to be sure. And I am away from my M491 so I cannot verify myself.

Question: I believe most of the earlier The M491's came from the factory with 7J and 8J wheels, (sporting a 944.xxx.xxx.xx part number) and factory wheel spacers.

In the later years, they came from the factory with actual turbo wheels (7's and 9's) with a 911.362.XXX part numbers. Yes/No? Thanks.

Early M491('84-85) cars came w/ 911 7ET23.3 & 8ET10.6 x18 and 28mm spacers only in the rear, from '86 the rears were 9ET15 x16 w/ the same spacer

There were no street M491 that were regular production cars prior to '84

The 930s from '75-80 used the same 911 7ET23.3 wheels but w/ a 21mm spacer, the hub design changed in '80 so the front spacer wasn't needed any more, the first few years on 930 also used 7ET23.3 ans 8ET10.5 x15 the first year 16s were offered was '77. These were all 9111 wheels as well.

[NY65912]

Yes. My '85 M491 has 7's & 8's. They went to 7 & 9's in 1986.

[Shaun @ Tru6]

My 84 has 7x8x16 and had no problem putting on 225/245 RE11s. Great tire, good size for the car.

[tdw28210]

Originally Posted by Bill Verburg

Early M491('84-85) cars came w/ 911 7ET23.3 & 8ET10.6 x18 and 28mm spacers only in the rear, from '86 the rears were 9ET15 x16 w/ the same spacer

There were no street M491 that were regular production cars prior to '84

The 930s from '75-80 used the same 911 7ET23.3 wheels but w/ a 21mm spacer, the hub design changed in '80 so the front spacer wasn't needed any more, the first few years on 930 also used 7ET23.3 ans 8ET10.5 x15 the first year 16s were offered was '77. These were all 9111 wheels as well.

Thanks. Hmmm....so maybe it's the wheel spacers have a 944 part number then?

[Dave Colangelo]

The Fuchs were an option on the 944 if memory serves and may have been standard on the 944 Turbos I cant remember. Im not sure why they would have switched the part numbers to a 944 part number but they are a legitimate 944 part as well as a 911 part.


Dave

[GeorgeK]

Originally Posted by tdw28210

Question: I believe most of the earlier The M491's came from the factory with 7J and 8J wheels, (sporting a 944.xxx.xxx.xx part number) and factory wheel spacers.

The M491 were never specced with 944 part number (951 wheels) fuchs.

[Matt Monson]

The Fuchs were an option on the 944 if memory serves and may have been standard on the 944 Turbos I cant remember. Im not sure why they would have switched the part numbers to a 944 part number but they are a legitimate 944 part as well as a 911 part.





Dave

They have a 944 part number because their offset is different than those used on 911s.

[GeorgeK]

Matt, there's more to that than just offset. The 944 part number 7X16 has the same offset as the 911 version, but a different face, allowing room for the brake calipers. It looks like a 6, but with countersunk lug holes.
The 8 has indeed a different offset, 23.3 vs 10.8mm

[RSM-M491]

TDW, you getting some new shoes for your ride?

[Bill Verburg]

Originally Posted by tdw28210

Thanks. Hmmm....so maybe it's the wheel spacers have a 944 part number then?

There may be a 944 wheel spacer but an M491 should have the following spacers
21mm 930.341.611.00 front
28mm 930.331.611.04 rear

back in the '70s there was supposed to be a 54mm, 930.331.911.04
but I haven't seen one. Doesn't mean they don't exist either as I have rarely been up close and personal w/ 930s

There was also 477.501.701 which is also a 21mm spacer and was I have seen these all over the place

[Bill Verburg]

944 Fuchs came in 2 flavors
7ET23.3 x16 and 8ET23.3 x16

both have BB clearance

[tdw28210]

Originally Posted by RSM-M491

TDW, you getting some new shoes for your ride?

Maybe. .

[tdw28210]

Originally Posted by Bill Verburg

944 Fuchs came in 2 flavors
7ET23.3 x16 and 8ET23.3 x16

both have BB clearance

Thanks again Bill. So is it possible that given that the 944 Fuchs have turbo brake clearance, that my M491 came from the factory with Weissach edition 944 Fuchs rather than 911 versions?

[Bill Verburg]

Originally Posted by tdw28210

Thanks again Bill. So is it possible that given that the 944 Fuchs have turbo brake clearance, that my M491 came from the factory with Weissach edition 944 Fuchs rather than 911 versions?

The odds are long, nothing is impossible though. The 930 brakes fit in 15s just fine.

[GeorgeK]

Originally Posted by tdw28210

Thanks again Bill. So is it possible that given that the 944 Fuchs have turbo brake clearance, that my M491 came from the factory with Weissach edition 944 Fuchs rather than 911 versions?

It has nothing to do with clearance on stock cars.
*Any* fuchs 15" and larger fits over std Carrera or 930 brakes that are original fitment.

When one fits 930 brakes to a 911 suspension, then special measures are needed in front, which is where the 944 numbered Fuchs enter the scene.

But on a factory specced car, turbo look or not, any fuchs 15 and larger fits.

[Bill Verburg]

Originally Posted by GeorgeK

It has nothing to do with clearance on stock cars.
*Any* fuchs 15" and larger fits over std Carrera or 930 brakes that are original fitment.

When one fits 930 brakes to a 911 suspension, then special measures are needed in front, which is where the 944 numbered Fuchs enter the scene.

But on a factory specced car, turbo look or not, any fuchs 15 and larger fits.

Not really George,
The front of the early 930 thru '77 had the same brakes as the n/a 911S, which used 6ET36 x15 wheels, the 930 used 7ET23.3 x15 which are the same 911 wheels that were used in the back of the 2.7RS, to fill out the fenders Porsche added a 21mm spacer, this spacer was used right up until the front hub redesign in '80, the hub redesign made the spacer integral to the hub so no more separate spacer but the wheels were positioned the same as previously, the 21mm spacer was also used when the big brakes were incorporated in '78. The wheel width and ET7ET23.3 was the same for 15 and 16" fitments, again standard 911 wheels are all that's needed.

In back the 930 has wider trailing arms that move the 8ET10.6 wheels out some, but they still needed spacers back there, the same spacer was continued for 15 and 16 and for 8 and 9 wheels. In '76 the Carrera 3.0 and the 930 used the exact same 7 & 8 x15 wheel sets and 205/50 & 225/50 x15 tires, std on the 930, options on the Carrera 3.0

[tdw28210]

Originally Posted by Bill Verburg

Not really George,
The front of the early 930 thru '77 had the same brakes as the n/a 911S, which used 6ET36 x15 wheels, the 930 used 7ET23.3 x15 which are the same 911 wheels that were used in the back of the 2.7RS, to fill out the fenders Porsche added a 21mm spacer, this spacer was used right up until the front hub redesign in '80, the hub redesign made the spacer integral to the hub so no more separate spacer but the wheels were positioned the same as previously, the 21mm spacer was also used when the big brakes were incorporated in '78. The wheel width and ET7ET23.3 was the same for 15 and 16" fitments, again standard 911 wheels are all that's needed.

In back the 930 has wider trailing arms that move the 8ET10.6 wheels out some, but they still needed spacers back there, the same spacer was continued for 15 and 16 and for 8 and 9 wheels. In '76 the Carrera 3.0 and the 930 used the exact same 7 & 8 x15 wheel sets and 205/50 & 225/50 x15 tires, std on the 930, options on the Carrera 3.0

^^^^^^^^

Seriously Bill, GREAT info. Thanks. But, how the HE!! do you know all of this stuff? I am beginning to think you a re a Google bot or something. : D

[GeorgeK]

Originally Posted by Bill Verburg

Not really George,
The front of the early 930 thru '77 had the same brakes as the n/a 911S, which used 6ET36 x15 wheels, the 930 used 7ET23.3 x15 which are the same 911 wheels that were used in the back of the 2.7RS, to fill out the fenders Porsche added a 21mm spacer, this spacer was used right up until the front hub redesign in '80, the hub redesign made the spacer integral to the hub so no more separate spacer but the wheels were positioned the same as previously, the 21mm spacer was also used when the big brakes were incorporated in '78. The wheel width and ET7ET23.3 was the same for 15 and 16" fitments, again standard 911 wheels are all that's needed.

In back the 930 has wider trailing arms that move the 8ET10.6 wheels out some, but they still needed spacers back there, the same spacer was continued for 15 and 16 and for 8 and 9 wheels. In '76 the Carrera 3.0 and the 930 used the exact same 7 & 8 x15 wheel sets and 205/50 & 225/50 x15 tires, std on the 930, options on the Carrera 3.0

Which is what I wrote/meant. Any stock 930 takes any 15'' and larger wheel.there is no need for the 951 specific rims on any 911/930 as they were delivered by the factory.

[tdw28210]

Originally Posted by GeorgeK

Which is what I wrote/meant. Any stock 930 takes any 15'' and larger wheel.there is no need for the 951 specific rims on any 911/930 as they were delivered by the factory.

Thanks for the clarification George. It is appreciated.