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Posted by: SirAndy Aug 8 2006, 11:44 AM

anyone know the thickness of the spacer needed for the 944 stub axles that goes behind the wheel bearing?

and yes, i did try the search ...
Andy


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Posted by: Aaron Cox Aug 8 2006, 01:47 PM

if you dont find an answer... try this.

torque stub to hub as in picture. measure distance from hub side of bearing area to stub side of bearing area. =A

then measure the width of a bearing. = B

A-B = really close to what your spacer needs to be

Posted by: SirAndy Aug 8 2006, 02:42 PM

figured that much, BUT ...

i don't have any good calipers here, otherwise i could probably measure it just using all the parts.

i *know* someone out there has done this before (hi clay ) ...
Andy

Posted by: slivel Aug 8 2006, 04:27 PM

You must be using 74 and later 911 hubs. If you have access to 69-73 911 hubs, no spacer is required.
Steve


Attached File(s)
 914_CV_and_Axle_upgradeweb.htm ( 6.66k ) Number of downloads: 98

Posted by: SirAndy Aug 8 2006, 05:52 PM

nope, take a closer look at the pic. the spacer is not for the hub, it's for the 944 stub axle ...
Andy

Posted by: Brad Roberts Aug 8 2006, 05:57 PM

I'll measure some spacers tonight for you. I know where this combo is sitting right now to go into a 914 I'm helping on down here.

I think is it .250 if recall. It is the same spacer used for the hubs he mentioned above. The Carrera hubs go right into our wheel bearings with a spacer, and the offset doesnt change.


B

Posted by: Brad Roberts Aug 8 2006, 06:01 PM

Andy,

the spacer will go on the hub.. the axle has to "enter" the bearing somewhat for proper compression of the bearing. You dont want to take up the slack at the axle.


B

Posted by: Brad Roberts Aug 8 2006, 06:02 PM

I'm confused now. Which hub is this? I cant tell from the pic (I'm getting old)


B

Posted by: 904svo Aug 8 2006, 06:16 PM

If your using later model stub axle and axle shaft you need 6mm spacers
that what I used on my 904 with 915 half shafts.

Posted by: SirAndy Aug 8 2006, 06:48 PM

now you guys got me all confused too ...

ok, just to make sure we understand each other, i'm using 944 (!) stub axles ...

here's what i measured (without any good tools):

- bearing when pushed together by hand: 37 mm

- 911 Hub bearing surface: 36mm
- 944 stub axle bearing surface: 6mm

so, according to this, i will need a 5mm spacer. does that sound about right?
Andy

Posted by: Cloudbuster Aug 8 2006, 07:24 PM

According to my 914-4 hub

The bearing surface between the face of the hub, and the face of the stub should be ~37mm.

The distance between the outer face of the hub (rotor bolting face) and the inner face of the hub (bearing face) should be ~33mm.

So, you may need to shim the hub also.

I also have a set of Patrick Motorsport shims for some 911 hubs. PMPCASPO is 5.1mm thick and used to adapt SC hubs. PMPCASPI is 6mm thick and I don't know what it is for.


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Posted by: ClayPerrine Aug 8 2006, 08:22 PM

On the 944 stub axle there is a shoulder. If you look at a 911 stub axle there is no shoulder. If you measure a 944 hub you will find it is shorter than the 911 hub by the same amount as the shoulder on the 944 stub axle.

To make a long story short, measure the shoulder on the 944 stub axle and make a spacer the same thickness.

Posted by: ClayPerrine Aug 8 2006, 08:27 PM

From the outside to the inside......

1. pre 74 911 hub.

2. 914 wheel bearing.

Here's where things get varied...

3a. 944 stub axle (find one with aluminum trailing arms.. it has the right one)

with spacer the same thickness as the step in the stub axle. This is to hold the inener race of the bearing in place.

3b. Alternate method. Take the 911 hub and cut the same thickness off the back of the hub as the step in the 944 stub axle.

4. 944 6 bolt cv joint on the outboard end.

5a. 914 /4 axle shaft. You have to cut it behind the splines to accomodate the 944 CV.

5b. If you did 3b, then you can use the 944 axle shafts. The difference in length of moving the stub outboard will allow you to use them.

6. 944 6 bolt cv joint on the inboard end.

7. Paper cv joint gasket from a 76 911.

8. 76 911 drive flange from a coarse splined 915 transaxle. It will bolt into a 901, and has the same bolt pattern as the 944 cv joint.

Posted by: SirAndy Aug 8 2006, 11:10 PM

geeze, why is this so difficult? when you say "shoulder" do you mean the machined down "bearing" surface that that HUGE red arrow in my pic points to?

because that picture *is* my current setup. what you see is a 911 hub that measures about ~36mm on the bearing surface and a 944 stub axle that measures about ~6mm on the bearing surface ...

that makes ~42mm of bearing surface while the wheel bearing is only ~37mm wide.
so, to get a schnugg fit, i'll need a ~5mm spacer on the stub axle side of things ...

is this correct?
Andy

Posted by: slivel Aug 9 2006, 07:03 AM

There is a spacerless solution. I have it on my 914. Parts list is attached. Several hours at junk yards found the right combination. The key is hubs and stubs from 69-73 911. They use the same wheel bearing as 914. Look it up in parts mags and you will find same part number. Axles are 86-89 944 with manual transmission. These axles have 100MM CV's and are very, very close to the same length as 914 axles. On trans side you use the output flange from a 76 912E or late 76 911S if you want course spline. Porsche must have used at least 6 different lengths of axles for the 944 series - 944 early, late, auto, manual, 944S, 944S2, 951 its crazy. You need 86-89 944 manual trans.

Steve


Attached File(s)
 914_CV_and_Axle_upgradeweb.htm ( 6.66k ) Number of downloads: 153

Posted by: SirAndy Aug 9 2006, 10:07 AM

ok, so, you mean that if i ditch the 944 stub and use a early 911 stub i won't need a spacer at all ...

i take it, the early 911 stub would bolt to the 100mm 944 CV?
Andy

Posted by: Mueller Aug 9 2006, 12:59 PM

great ...now what to do with the spacers I made last night??????

Posted by: JOHNMAN Aug 9 2006, 02:47 PM

What would that spacer accomplish?

As I understood it, a spacer with the same ID as the bearing and 4.5 or 5 mm thick would be required for Andy's current 944 parts.

Am I wrong?

Posted by: Mueller Aug 9 2006, 02:51 PM

I have no idea....I was just asked to make one...seems like the OD should be larger to prevent the hub from pulling out of the bearing...I'm confused as well

Posted by: slivel Aug 9 2006, 03:03 PM

When people use the later 911 hubs a spacer must be used because the bearing is wider in that application. The spacer is used in this case to take up the space the the wider bearing would occupy as someone mentioned earlier in this thread. The 914 wheel bearing is the same as early 911 (69-73) so early hubs need no spacer. Part number for both early 911 and 914 wheel bearings is the same - 999 053 021 00. The next decision point is size of CV joint. There are three choices for Porsches, 94MM, 100MM, and 108MM. So you must pick the stubs and trans flanges and axles to match up. There may be other combinations that work, but I know that the 100MM CV's on 86-89 944 manual trans cars are almost identical in length to 914 axles. I was worried about clearance issues with the 108MM (930) style CV's fitting inside the suspension arm.
Steve

Posted by: JOHNMAN Aug 9 2006, 03:15 PM

The stub axles shown in the pic above have an area turned down to an OD that looks in the pic to be the same as the ID of the bearing. I believe that the spacer requested would need to fit that shoulder so that a 914 rear wheel bearing would be clamped between the hub shown and the stub shown.

Posted by: Mueller Aug 9 2006, 03:20 PM

Looking back at Andys 1st post, I mis-understood the question and photo, so I guess I f'd up and made the spacer to mimic the 944 stub axle which was the wrong thing to do, I need to make the OD of the spacer equal to that of this surface in red???

Posted by: SirAndy Aug 9 2006, 03:25 PM

the spacer needs to fit on the bearing surface ... you'll need a 944 stub axle to see why ...
the 944 stubbies have about ~5mm of surface equal to the bearing surface on the hubs ...

meaning, your spacer has too small of an inner od ...

keep up the good work, almost there ...
Andy

PS: the hubs i have are the early 911 style that use the same width wheel bearing as the 914.
the problem is with the 944 stubbies, not the hubs ...

Posted by: Mueller Aug 9 2006, 03:38 PM

I made the ID ~1.20 to fit the 914 stock axle with the OD being ~1.65..oh well, it was a messy learing experiance (used an old piston from a set of 914 calipers to make the spacer )

Posted by: SirAndy Aug 9 2006, 03:52 PM

actually, make that 6mm width ... it's easier to shave some off then add some on later ...
Andy

Posted by: ClayPerrine Aug 9 2006, 07:14 PM

That is correct. You need the spacer ID to fit over the shoulder you pointed at in red, and the OD to be the same as the unmachined portion of the stubbie you're putting them on.

Also, you need to add a 1.5mm bevel inside the spacer to account for the rolled edge on the stubbie, otherwise it won't sit tight against the rest of the stubbie.


Or you could just shave 5mm off the axle flange and be done with it.

Posted by: Mueller Aug 14 2006, 01:28 AM

okay, okay...here are the "correct" ID/OD spacers