BSR&D 928 Super Bearing and Clamp Photos + Pricing!
04-21-2009, 11:17 PM
#46
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A few years back, the conventional wisdom was that the older, constant diameter (25 mm) shafts were superior (well, at least less likely to self destruct) to the 28 mm shafts, so when I blew the one up on my '90 S4 about 8 years ago, I replaced the TT with one with the 25 mm shaft.
What's the latest thinking? If I were to go with new bearings and clamp, should I return to a 28 mm shaft? Especially since I'd like to add significant HP (supercharge) in the near future?
What's the latest thinking? If I were to go with new bearings and clamp, should I return to a 28 mm shaft? Especially since I'd like to add significant HP (supercharge) in the near future?
04-21-2009, 11:45 PM
#47
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Hi Ed,
Great question!
The 25mm constant diameter drive shaft is a great drive shaft with no stress risers built into it as the 28mm drive shafts that came that way from Porsche. The stress riser being the somewhat severe neck down from the 28mm shaft portion to the front splined portion of the shaft.
What we have seen is that the 25mm and 28mm can both splinter if not examined periodically for any damage in the shaft where rust can form and further weaken the shaft leading to a catastrophic failure.
If you are supercharging I would keep the 25mm shaft. 25mm shafts have been used in high horsepower cars such as Mark Andersons 928 racer and 944 racers, to include V8 converted 944s, with good success. However since they are made of metal and getting older, they can and will fail sometime in the future. Nothing lasts forever.
HTH,
Constantine
Great question!
The 25mm constant diameter drive shaft is a great drive shaft with no stress risers built into it as the 28mm drive shafts that came that way from Porsche. The stress riser being the somewhat severe neck down from the 28mm shaft portion to the front splined portion of the shaft.
What we have seen is that the 25mm and 28mm can both splinter if not examined periodically for any damage in the shaft where rust can form and further weaken the shaft leading to a catastrophic failure.
If you are supercharging I would keep the 25mm shaft. 25mm shafts have been used in high horsepower cars such as Mark Andersons 928 racer and 944 racers, to include V8 converted 944s, with good success. However since they are made of metal and getting older, they can and will fail sometime in the future. Nothing lasts forever.
HTH,
Constantine
04-21-2009, 11:56 PM
#48
Side question. Nearly unimportant enough to not ask. But I will anyway.
Does your rebuilding technique involve any usage of clamps on the outside of the tube? What I usually do is strip down the tube, get it sand blasted, and then powdercoated. Then I run different wire wheels down the tube to clean it out properly. THEN I put the new stuff in.
What I am asking is if you get a powdercoated tube, will it be affected by your rebuilding technique?
Does your rebuilding technique involve any usage of clamps on the outside of the tube? What I usually do is strip down the tube, get it sand blasted, and then powdercoated. Then I run different wire wheels down the tube to clean it out properly. THEN I put the new stuff in.
What I am asking is if you get a powdercoated tube, will it be affected by your rebuilding technique?
04-22-2009, 12:33 AM
#49
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Hi Brendan,
And no question is too small to answer!
Our technique will not harm your powder coated finish. I would recommend you pack it carefully for the trip to us to protect the finish, but you already know that.
The only question I would have is how aggressive were the wire wheels used inside of the tube? If they changed the ID of the tube there is a possibility of the bearing units not fitting correctly to stay put. Then again this problem would also be present, if not more so, for the OE bearing units.
Cheers,
Constantine
And no question is too small to answer!
Our technique will not harm your powder coated finish. I would recommend you pack it carefully for the trip to us to protect the finish, but you already know that.
The only question I would have is how aggressive were the wire wheels used inside of the tube? If they changed the ID of the tube there is a possibility of the bearing units not fitting correctly to stay put. Then again this problem would also be present, if not more so, for the OE bearing units.
Cheers,
Constantine
04-22-2009, 01:27 AM
#50
Oh, yes, good point. It was fine with the OE carriers on the previous tube.
04-22-2009, 03:01 AM
#51
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05-15-2009, 08:52 AM
#53
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Just an update.
Have sent out the first sets of Super Bearings to customers. Have a few sets left of both the steel and aluminum versions.
28mm inserts for the 28mm drive shafts coming within a month.
Cheers,
Constantine
Have sent out the first sets of Super Bearings to customers. Have a few sets left of both the steel and aluminum versions.
28mm inserts for the 28mm drive shafts coming within a month.
Cheers,
Constantine
