Yet another 5-lug rear conversion, some questions Options

[TonyAKAVW]

I've been reading up on lots of threads about the rear conversion, CV joints, etc. etc. I'm not 100% clear on everything, but more importantly I'm not exactly sure what I have...

A few years ago I picked up a roller that was in the early stages of a -6 conversion. The owner worked at a Porsche shop here in socal, and had put a 1987 SC front end on the car, and started to do the 5-lug rear conversion.

So what I have are a pair of trailing arms with some stuff installed. From what I can tell from the other threads, I have a 74+ hubcentric wheel flange, early 911 stub axles, and on one of the trailing arms, a partially complete 911 handbrake. The other trailing arm has the dust shield portion installed, but no shoes, etc. The stub axle flanges measure 100 mm across in total diameter (edge to edge).

Now for the questions:

1. There were several threads about spacers required for the hubcentric wheel flanges, but I couldn't figure out where these spacers are supposed to go. Second, is there a way I can tell if this setup has them or not?

2. I'm hoping to use the 944 CV joints, 914 axle, and 911 coarse splined output flanges. Based on what I have are there any issues?

3. Brakes. I currently have the A calipers on the front and stock 914 rear calipers. When I finish this rear 5-lug conversion I will have to choose between upgrading the rears to the V-calipers or moving my A calipers to the rear, and using Boxster calipers on the front. As far as I can tell, there is little to convince me to go with the V-caliper. A set of Boxster calipers is ~$300 off ebay, and I figure I should be able to make a set of adapters on my milling machine. The V-calipers are nearly $600 and offer no change in pad size on the rear. I realize that fora narrow bodied car, the setup I'm proposing is overkill, but if in the future I decide to flare, I'd have the brakes already done. I have a 165 HP Subaru motor, and I'm sitting at about 1900 lb right now, with some weight still to come off. So the question here is any suggestions/opinions?

4. If I do put the A calipers on the back, are they strictly bolt-on or will I need to modify anything?

-Tony

[TonyAKAVW]

Craig: Nicely done! I think this is what mine will look like in theend. It looks like you left the cable end holder in the stock spot. Is the stop plate and 'rubbing pad' piece welded to the trailing arm? I can't quite tell from the picture.

Are those Boxster calipers?

[Richard Casto]

Looks good Craig! (IMG:style_emoticons/default/smile.gif) I am also curious if you were able to leave the cable end mount in the stock place or not. I am assuming that is a stock 914 cable with a custom extension correct?

[Wes V]

I've adapted the 944 e-brake spreader to my car and have been using it for 3 months now it it works great.

What a "teaser" photo!!

Looks like everything was addressed. I really like it.

How about more information and photos. Please don't tell me that you fab'd up the whole thing and didn't take photos.

Wes

[charliew]

It looks like he also used the angle iron to make the block and rubbing support. Great job.

[davesprinkle]

One last thing to mention. Brad may know something beyond what is listed in PET, but I just looked up the part number for the 986 and 987 and as far as I can tell they list a different part number for the bearing than they do for the 914. Frankly I would be suprised if they used the 914 bearing. They increased the bearing size in later cars (probably due to load from increased weight and performance of the newer cars) and I would not expect them to go backwards with the Boxster. But I don't know any more than what I can see in PET.

According to BR, the Boxster and 914 bearings have identical dimensions, but the Boxster has a higher ball count, hence the different number.

[Richard Casto]

One last thing to mention. Brad may know something beyond what is listed in PET, but I just looked up the part number for the 986 and 987 and as far as I can tell they list a different part number for the bearing than they do for the 914. Frankly I would be suprised if they used the 914 bearing. They increased the bearing size in later cars (probably due to load from increased weight and performance of the newer cars) and I would not expect them to go backwards with the Boxster. But I don't know any more than what I can see in PET.

According to BR, the Boxster and 914 bearings have identical dimensions, but the Boxster has a higher ball count, hence the different number.

Ok, drop in replacement, but not same bearing. Good info for me to use on the wiki article. Anyone checked the price yet of the 914 vs. Boxster bearings?

[TonyAKAVW]

Boxster Bearings at Pelican Parts are $36.75 versus $77 for 914 bearings. I will probably use a Boxster bearing to replace my 914 bearing that I had to destroy in order to check if I had a spacer.

[charliew]

Tony use the junk bearing in the castings while you are welding on them to save ruining a good one.

[davesprinkle]

What is the spline count and diameter inside the hub? Or another way of saying this, what stub axle will work with that hub? Will only the Boxster stub axle work, or will others?

If only the Boxster stub axle works, then what is the CV joint situation with the Boxster stub axle?

BR indicated that the Boxster stub-axle and outboard CV are one piece and are non-serviceable.

Meaning that the Boxster stub-axle is a likely a dead-end for 914 driveline conversion, at least as far as a bolt-up solution is concerned.

[charliew]

I bought a 944 stub axle on ebay. When I got it, it had the outer part of a cv made onto the axle stub. You might be able to put the 914 cage and balls inside the cv/stub. I really don't know if it was a 944 or a boxter part. It was so cheap I thought I would see what it was.

[craig downs]

Craig: Nicely done! I think this is what mine will look like in theend. It looks like you left the cable end holder in the stock spot. Is the stop plate and 'rubbing pad' piece welded to the trailing arm? I can't quite tell from the picture.

Are those Boxster calipers?

Thanks Tony
I've got boxster calipers front and rear.

I left the cable end mount in the stock location but cut it off to line up the cable to the spreader and rewelded it back to the trailing arm. I fabed the shoe anchor out of angle iron and welded it to the trailing arm.

I was going to do a thread on how I did this or would you like me to add it to yours.

[TonyAKAVW]

Please add it here!! Would love to see that. I think I will take a look at Boxster rear calipers, might be another option to consider other than the M calipers...

Are you running 15 inch wheels with those calipers? I have 15" cookie cutter wheels and would like to keep using those...


-Tony

[craig downs]

Ok I'll start adding some tomorrow. I have the early 15" deep 6" fuch and they just fit.

[Wes V]

Ok I'll start adding some tomorrow. I have the early 15" deep 6" fuch and they just fit.

Craig;

I think it should be on a new thread!!!

This string starts out covering a lot of stuff that isn't specifically about e-brakes.

I'd hate to see what you have done get buried where people don't see it without reading three pages.

Wes V

[TonyAKAVW]

Wes is right. It would be a lot easier to find if it were in its own thread.

[charliew]

And be sure and say using the angle spreader, that spreader can be bought by itself as it's also on bmw's, and the support with the rubbing blocks and the 914 extension. For the guys that have the early shoes already they can use them with a small notch ground in them and if they ever wear out then they can go to the 944 style shoes. There is a straight pull that looks very much like the angle pull so be careful on buying the spreaders by themselves. The straight pull, not the early 911 butterfly type, are on the earlier aluminum bananna arms, I think about 74.

I found at least two porsche yards that were very familiar with the individual pieces of this conversion. When I called the yards they said yeah you want the 65-68 911 backing plates off of the steel arms (I don't think there are any alum. ones anyway) and the rest of the stuff off of a 944, it'll take a coupla hours to take the parts off. It was about 160.00 to my door. Make sure you ask for good useable shoes and the least pitted backing plates they have.