Miles965uk

I see there is a different part number to these and wonder if you can use an RS wheel bearing in a NA hub (mainly the rear hub I am interested in here)
or what is the difference? Im only interested if it has better performance i.e can handle higher loads i.e wider and large wheels...

Cheers alot

Cupcar

Interesting question.

The 964 Carrera RS and 964 Carrera RSR 3.8 use the same rear trailing arm but use a different bearing 999.053.042.06 for the RS and 999.053.042.08 for the RSR. The RSR part is a racing part not available at the Porsche dealer. The retention hardware -bolts and plates-is the same as well for both cars so I presume given that all the parts surrounding the bearing are the same, one could use the RSR bearing in the RS.

Furthermore, the same bearing used in the RS is also used in the normal C2, so the RSR bearing could presumably be used in a normal C2 as well.

The hooker is, the Turbo uses 999.053.050.01 part number bearing so one can't with certainty say the RSR bearing would work in a Turbo.

I don't know the differences between the bearings, I would think the RSR bearing to be a heavier duty part though.

Miles965uk

ahh yes thats right, in my parts list ive got Bearing for a C2/4 999.053.042.01 and then later it was changed to 999.053.042.06 which is for both RS and C2.... so theres my first problem solved.....but I never thought of the 3.8!... if they use the same arm then possibly it will fit as you said- the 3.8 does use a much wider rim and tyre than anything other 964 so THATS what i probably really need!

So any idea who can sell these?

Thanks

Bill Gregory

Gert at Rennlist sponsor www.carnewal.com can order parts from Porsche Racing.

Miles965uk

Thanks Bill, have called... just waiting for a reply...

Cupcar

Here is a little bit of trivia that might interest you. Read below Porsche literature, note their is an RS type "control mount" is for the European (ROW)Turbo 3.6 ONLY, the USA model has a the same control arm as the 3.3 Turbo with the toe correcting bushing design.

Also note the mount is pressed in to allow 20 mm lowering of the car, the RS is lowered 40 mm so perhaps this is why the RSR and RS use a different part number control arm, same bushing but for lower ride height in RS?

IrocMan

Hi,
Is this a 964 on this picture ?

Cupcar

Yep, 964 Turbo 3.6

Miles965uk

Thanks alot cupcar- thats is really helpful. I heard the bushes had been pressed in differently... so I guess I could compare my 3.6 to the NA arm side by side to see how they pressed the bushes in differently exactly... but actually saying that I dont think you can buy seperate bushes for the rear yet! perhaps ill contact powerflex as they do some for the front- they might do some for the rear one day.

Im still waiting to finding out if I can get hold of a pair of RSR bearings or not. will update this post if I can.

Cheers

Cupcar

The mount is more than a normal mount at a different angle, the mount is redesigned with different internal washers to limit axial movement. Presumably these are already in your European Turbo 3.6.

See below taken from the RS Carrera book published by Porsche.

Miles965uk

Hey you dont know how much I appriecate the info! You mind telling me what book it is where the 3.6 turbo info came from?
So theres more then just some bushes placed differently. Yes it should be on my 3.6.... and I will start to look at them vs these NA arms I bought more closely.
I wish to emmulate the RS/RSR arms as much as possible with the NA arms and parts from my 3.6 arms - if at all possible! without buying those really expensive RSR ones.

Cheers again for the valuabel info

JasonAndreas

Miles,
According to Adrian's book (page 260) your rear trailing arm can be machined to accept the RS style bushing assembly.

Cupcar

Miles-
Given that the part number of the 964 RS and 964 RSR 3.8 trailing arm is the same means they use the same trailing arm.

Given that the only difference in the RS/RSR trailing arm and a normal C2 trailing arm is the control mount.

Given that the RS/RSR and 3.6 Turbo have different part number trailing arms means they are not the same.

Given that the 3.6 Turbo has the identical design RS/RSR control mount.

One can only deduce that the only difference between the 3.6 Turbo and RS/RSR trailing arms is the angle the control mount bushing is installed at. This is done to adjust for the fact that RS/RSR cars are lower than the 3.6 Turbo.

So, I wouldn't change a thing unless you are going to lower your car another 20 mm or so from stock and even then I wonder if it is necessary.

The information I cited comes from the Porsche factory books titled Porshe Service Information Technik '92 911 Carrera RS and the Porsche Service Information Technik '93 911 Turbo 3.6

Miles965uk

superb! However im sorry i didnt explain what i was upto at the beginning of the thread- i am changing my arms to NA arms to fit a wider wheel and tyre set in there.
So the main thing was to see if I can make the NA arms into and RSR -type with the control mount and bushings... and also the bearing- seeing what you have pointed out I would think the bearing of the RSR will fit into the NA arms.... I will fit out fairly soon tho when I get stuck in!

Geoffrey

Just purchase the ERP monoballs for the N/A control arm and you'll be fine. You may also want to update to the ERP 935 style plates. However, if this is a street car, I'd recommend retaining the rear rubber bushings.