We all know that 69-73 911 rear hubs are getting scarce and pricey. I went out on a limb and bought a whole rear 99 Boxster assembly for $41 delivered on EBAY. It is a well known fact that the 914 and the Boxster use the same wheel bearing. So I figured it would be an easy swap. I drove the hub out of the bearing and started the comparison of the two hubs. I had a 69-73 911 rear hub and a -6 stub axle to use as a baseline. The Boxster hub has the same splines as the 911/914-6 stub axle so it was a drop in fit. One down, so I put them side by side to find out they are the same height. Now have two down, the last check was to set the rotors on both hubs to see where we were at. Bingo, they matched up. So the stub, the hub and the height are all the same. HOWEVER, there is one area to be addressed. the -6 stub sticks up about 5mm past the center of the hub. It is going to require a spacer to fill in the area so the washer and nut will tighten down. I am thinking that the one that Patrick Motor sports will do the trick. I think it will be worth trying because I am using Boxster wheels.

Tell me what you think.

IIRC, the Boxster stub axle is a 6 bolt that is the same size as a 944 turbo CV joint. Use the Boxster hub and stub, and then use the 944 CV conversion procedure.

Should be a complete bolt on for a 914.

Because I have a set of early 911 trailing arms in the back of a very cold barn....
Could you explain what I might be able to use from an old 911 trailing arm to help me switch to five lugs?

So, you need to disassemble the axle from the Boxster and get the stub off then. I will see if I can find one. I like the idea of using the 944 CV conversion.

The trailing arms need to be 69 or later to be used for the 5 lug conversion. You will need to take the 5 lug hubs out of the swing arm. If you have the stub axle from the axle you can use them too.

This could be a very productive thread. Nice job.

I will drop my hijack in one last question.
How do I know what year these trailing arms Are from...

Early 65-68 arms have a long stub axle and long hub. 74-Up are aluminum. Go to ebay for early 911 trailing arms or rear hubs and look at the images. Hope this helps.

Excellent work.

One quick question...what year / years were those Boxster rear hubs?

I used a 97-04 boxster rear hub. Part number 996.341.605.54 on the hub. I just ordered a Boxster axle to check out what Clay said about getting the stub off and using a 944 CV Joint.

Nice!

Watching with interest.

This would be a nice option for a subaru engine/trans conversion. Use the boxster axles and respline them to except the subaru cv on the trans side.

New interesting development about the axle. I paid $60 for a used one and I could have gotten a NEW aftermarket one for $81 shipped with new bolts,straps and axle nut. I am guessing they are the same as some part used on the the VW/Audi line of cars. It will be Tues or Wed before used axle shows up.

A good and productiv thread

I agree, this is an interesting development. I have all the original parts for the six, but when the time comes to replace the CV's this system looks to have great potential.

Any updates?

Having a hub centric option for the rear would be great.

I will be working on a update for this weekend. Boxster axles came in but they do not look promising. -6 rotor will require new holes to hold rotor on boxster hub.

The 964 front hub looks like it may be another option as it uses the same wheel bearing. It would be a matter of finding out what stub axle will work though. It may be an area from some one else to explore.

Very cool thread.

Is that for the C2 or C4?

For as long as I had my 964 C2 I never took it apart luckily!

964 with splines in front should be c4

Great job, keep it coming

I am not going to make it to the shop until this coming weekend. I sprained my wrist and hyper extended my thumb. It does not look like the Boxster axle or stub will be an option. Might be a source for used 110mm cv joints though.

Does the 911 stub also have the 5mm stickup or just the -6?

I just brought home a set of 108mm cv axles with the stubs on, now I am jonesing to order Boxter hubs.

Cheers,
Scott

Really jonesing so I went looking for more info and found this:

Hubcentric Hubs with 911 Stubs for Sale

No mention of spacers or machining.
Does this really work?

Cheers,
Scott

Yes, the 911 stub axle sticks up the same amount as the -6 stub.

Great job. Thanks. Keep the details coming!

You can see her what you will need:
http://www.patrickmotorsports.com/part/914...conversion-kit/

I had thought that also but Patrick Motorsports has the note:
"THIS ITEM IS DESIGNED FOR USE WITH 5 LUG CARRERA AXLE FLANGE"

My understanding is that the Carrera uses a differnt (wider) bearing and therefore requires the spacers for preload and to put the brake rotor in the correct plane.

http://www.914world.com/bbs2/index.php?act...=2&t=234009

Isn't the advantage of the Boxster part that it uses the same bearing and therefore could be used w/o spacers?

So much information in so many different places.

Cheers,
Scott

Just a question: Are the Boxster parts better/cheaper than the Carrera parts? There seems to be no shortage of them out there.

Whole rear Boxster hub assemblies can be had for less that $50 shipped on Ebay. You will have about 5 lbs of scrap aluminum when you are done.

Ok, here is the last of what I have found out using the Boxster and later 993 axles. The 911 and Boxster axle are the same length, are hollow tubed and use a 28 spline. The 911 axle is 32 mm thick and the Boxster is 28mm thick. Both are to long for 914 use. The Boxster S inner CV is a 911.332.030.01 , 108mm and 32mm thick. It is used in bunch of Porsche applications including the 930 Turbo. The 911 inner CV only had a Lobro part 7253150199001 and it is only 28mm thick. Both CV's used a 928.332.293.02 boot.

I had some 110mm 911 stub axles so I bolted the CV's up. I see no reason why the CV would not work for this application with joint gasket.

The outer stubs are a completely different item. The flanges are crimped on and no replacements are available. CV joint cup could be machined off and holes drilled. Not cost effective to use them. The overall height is the same but each is machined differently.

In summation the only useable part would be the Boxster hub. The 914-6 rotor would have to be drilled and screw holes countersunk to allow the hub to be screwed to the hub. The 911/944 stub axle will required a 8mm spacer at the top of the stub axle so it can be tightened down.

So, I spent some money and learned some new information. It seemed like a good plan at the time but NOT worth the cost of modification required to make it all work.

Thanks for the intel Mark. Looks like we can put this one to bed then.

+ 1 on Woody.

Just a heads up any big type 4, like mine or Woody's will destroy a stock set of CV's in one autox. Haven't yet destroyed a 944CV.

I am still planning to use the hubs. Still cheaper than tracking down early 911 hubs plus the hub centric benefit.

I know i'm going to get flamed but will the 4 lug wheel, cv stub fit into the boxer hub ? I know this would not give the bigger CV. I have not pulled down one yet to look at the stub.
Thanks,Randy

There are some variations on this:
The 986/996 use the same hub at the front with a stub axle. That front stub axle is not drilled for CV, it just has the ABS reluctor/exciter sawtooth cuts. That would be a better starting point for conversion item (i.e. welding on a 6 bolt CV flange)

Patrick Motorsports used to sell a set of washers to use the wider, later 911 hubs/stubs in a 914 trailing arm. The P/Ns were something like PMPCSPI and PMPCSPO. I don't know if that changes the CV or brake rotor offsets.

Apparently, you can use the later hubs and the wider axle bearing in the 914 trailing arm, you need a specially machined bearing retainer plate that is countersunk to deal with the excess width. Maybe Patrick makes something for that, too. (Same disclaimer about CV and rotor offsets)

seems like a great research for future use

Or, you can just use real 914-6 hubs/stubs for your conversion.

I ordered in some Box outer hubs.


If I read this post right. I need a 911 axle/stub, drill and tap for a rotor mount and a spacer .?

With my build being a Subaru motor and trans , what outer CV will be needed ? Being new to this it looks like a 911? Is it the same as the 944 CV ?

My plan is to use the axles from ColdWater914. Subaru on the trans and it looks like 914 or 944 on the axle.

With this in mind ,if I go with a 911 rear vented rotor with 911 parking brake and kit. What will this change ? What will I also need ?

Please take it easy on me,I'm old.
Randy

Here is a little add to using the Boxster hub. I made a small cut on the stubs to make resesed in the 108mm hub. Don't forget the radius when cutting the stub . And to reuse the nut and the holes in the stub I made a washer/spacer.

^Looks good, instead of cutting the stub axle I would have just added a chamfer or radius or counterbore to the spacer.

Yep, I looked at that but wanted just a little more contact . Like .007, LOL .

Make sure your spacer is as hard as your nut (HRC) or you will have gaulling on your bearing surface and end up with a lot les clamp load in your joint.

David

Thanks David,I will keep a eye on that.

So it will not be plug and play. The the hub will need to be cut to clear the bearing flange. If you look at the green paint ,its missing.









Going to be tight in their with the 108's !



And I stopped at Patrick Racing and got the trailing arm stiffeners. Welding in the AM.



One last thing,I don't think it will need any cutting on the stub shaft. More in the AM. But I have a set !

Any chance the Boxster bearing flange will bolt to the 914 trailing arm.

Cheers,
Scott

Good idea. I will look at it tomorrow. But I don't think so. It is a non-symmetrical pattern on the Boxster.

If I built a holder I could cut down the bearing flange shoulder ? Maybe in the field it could just be ground down ?

I will cut one of the stubs and see what clearance will be needed. Need to take a look at the 130x4 hub.