Just like the titles says, I'm looking for someone who does the redrill with the welded bosses. If not, I'll do it myself. I'm just looking to support someone who might do it more often than myself.

Thanks,
Thomas

PMB

Hey Thomas, PMB is the way to go!

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The last set of re-drilled rear hubs from PMB were done to accept the screw-in type lugs. Nice thing about those is you can change the lug length w/o having to remove the hubs.

I am interested in this as well, so maybe I am ignorant but what does PMB stand for?

Pmbperformance.com. he is the go to guy for breaks and a whole lot of other things,also a member and admin here in the "world "go to his website nice guy Eric Shea.

Thanks I appreciate the information

Bruce Stone can also do them.

Sorry to jump in on this but what is "welded bosses"

When hubs are redrilled, 4 of the lugs will be in areas where there is no "boss" or extra material on the backside of the hub, as they were from the factory. I've already seen an example of those lugs actually started pulling through the hub (on a V8 track car with slicks) to the point where the hub was "wavy" enough to cause the brakes to rub back and forth on the rotor as it was spun by hand. On a street car probably no big deal, but anything on the track needs to have those 4 redrilled holes "beefed up" with more material, i.e. the welded bosses. In the picture below, these hubs were drilled but not reinforced.

If I get this right - early hubs had additional bosses to drill and tap. Later hubs can have extra metal (bosses) welded on to duplicate early hubs.

I'm holding some front 5 lug parts for you, if you want 911 rear hubs, let's talk, trade, ect. You know my #.

Here is a set I got a while ago. Holes were beefed up.

My hubs has no additional metal added on the drilled holes but at least it is a theaded hole. I can easily change my theaded lugbolts.
yup my trailing arm looks rusted but it is not, it is the original copper metallic of the car.


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Ah I see I will machine some up.. Mark still need those fronts got so much cash you going out for these oil tanks and now for the headers gonna be a bit.. We will talk soon.

Just curious, will the 911 rear hubs interchange directly with the stock 914s? I'm still learning a lot of this and seems that would be the strongest solution...

[url=http://www.914world.com/bbs2/index.php?
Read Eric Shea's write up here -

Early 911 hubs will with 911 stub axles that bolt onto your existing axles but 78+ require spacing and the use of 911 axles and adapters to the input flanges of the 901 gearbox.

Thomas

Thank you for all of the replies Gentlemen!

I had no idea Shea was still doing the 5 lug hubs. For some reason, I thought he backed out of doing them. I'm glad to know, just wish that info was on his site. Has anyone done this recently to know a rough cost for 2 hubs?

Thanks,
Thomas

I wonder if welding the washers on to reinforce the hub, but not doing any post weld heat treating makes the hub an unknown item; maybe more brittle than just drilling the holes, and studding? (I am not a metallurgist, but know best intentions sometime back fire.)

All depends on what process is used to make the hubs they look like some sort of forging?

I'd say forging or very nice investment castings.

I would be more worried about cracking from too sharp of an inside corner of the spot facing than the HAZ.

That being said I have not heard of one failure from this modification.

They are cast.

Post your pictures of broken hubs. I've only seen one, ever. It was caused by a guy drilling out holes with a power drill.

Hubs, drilled, bossed, press in, spot faced etc. are never your weakest link. Your CV's are.

Here's my take for a 914-4 hub:

1. These are fine for applications up to 140hp. The hp limit is NOT because of the hub, it is because of the CV that will attach to the stub axle that you "must" use because of the odd 914-4 spline count.

2. The early 1970 hubs have extra bosses all around meaning, the factory had planned on using them for their 5-lug cars, be it the -6 or, perhaps an "option" offering. They're nice for either drill in studs or press in studs but, not necessary.

3. When spot facing later hubs for press in studs, it will take the face down to 3mm. that can be slim but again, I've NEVER seen a failure when they're done properly. We use to weld in bosses but it was expensive and overkill, ESPECIALLY for a hub that will inevitably be connected to a Type 1 CV.

4. We like drilling them to 14x1.5 now because it leaves for full engagement and there are some very nice screw in stud options out there. It is important that you USE RED LOCTITE when going this route. It will handle anything you can throw at a Type 1 CV.

5. For higher hp applications I recommend early 911 hubs.

My guess would be cast steel though not iron?

Definitely cast steel. Iron would likel be way to brittle for the application.

Thanks for chiming in Eric! I tried calling you on Wednesday morning but it said you were closed. I just need a set of rear hubs. Will PM you.

Thanks,
Thomas

We took a much needed phone break.

I could understand. I'll call after this holiday weekend.

Thanks,
Thomas