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TBF clamp fix offer - long

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Old 03-10-2005, 07:57 AM
  #46  
Black Sea RD
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Hi Bill,

That's something to work out with the manufacturer, I'm sure once they have a process for making them figured out it wouldn't be too hard to make smaller batches. Our's was a one off so no process exists yet to make multiple units.

Now comes the part where the Big Three have to be contacted and pitched this idea. I think it would be a good product for all of them to carry since they all have customers who buy from them and can order this clamp when the time is right to do so. They will each be able to make a bit on each sale. Since DEVEK works on customer cars and will now be offering SC systems, it would make sense for them to have some on hand. I think this clamp would be a natural choice for SC cars with increased HP/TQ.

It would be helpful if the Big Three heard about this from others, so anyone out there who would like these to be available in the future drop then a note and soften them up a bit for our pitch.

Thank you for the suggestions.

Constantine


Originally Posted by Bill Ball
If the MOQ stays at 25 after the first order, then yes, there is a problem. If the Big 3 each took 8 (and I took one, as I offered already), then the part gets made. What happens when one of the Big 3 gets low and needs to re-order? I saw that problem when I agreed with bigs, so I left that out. If the MOQ is 25 then one needs to assume the risk for the whole lot or it won't work.
Old 03-10-2005, 10:43 AM
  #47  
heinrich
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While I love this solution, I wonder if the better answer would not have been the exact opposite, in other words having the tube and shaft float inline with some play?
Old 03-10-2005, 05:03 PM
  #48  
Bill Ball
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Heinrich:

Designing a floating/sliding mechanism without changing the shaft splines is the problem. The splines are too shallow and not machined to be held loosely. You'd have to clamp something more substantial to the splines that was hardened and otherwise designed to slide in some kind of housing that was bolted to the flexplate or some replacement for the flexplate. Sounds doable but probably way expensive. Worth further thought.
Old 03-10-2005, 05:21 PM
  #49  
borland
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Outside of an interference with the bolts to the flexplate, it might be much cheaper to utilize the factory coupling, machining in the design features of the so called TBF fix coupling. Might be improved too, cause the splines are already cut. Instead of $375, the costs might be $150 plus exchange.

Course lots of automatics that have survived all these years with proper maintenance, without TBF. Rebuilding the TT and replacing the torque converter bearings every 75K miles highly recommended.
Old 03-10-2005, 11:06 PM
  #50  
heinrich
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Hmmmm interesting Bill, yes I hear you. Borland has a good thought ... wonder about that. I guess what I'm saying is, I think of the issue as one that cannot be fixed by a permanent, immovable clamp. I mean, that is what we have now, only not immovable .... the rear can still pull and in fact I wonder if this might not stress the pressure plate to the extent that it might experience metal fatigue, or the tt to cause failure there. If we used something like this innovative design, and coupled it with a U-joint or floater ... that would IMHO be the fix. Of course, we're talking impossible due to cost.
Old 03-10-2005, 11:10 PM
  #51  
Black Sea RD
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Hi Heinrich and Bill,

Please see post #30. I have photos of this sliding assembly, send me a pm if you want to see it.


Hi Borland,

The "so called TBF fix coupling" is a drastic departure from the original clamp, no way to machine the old clamp to make it.

Your right, lots of autos are alive and well after many miles. Again this clamp was made to stop the driveshaft creep and subsequent forward pressure on the front flexplates which could lead to TBF.

What evidence do you have that rebuilding the TT and replacing the torque converter bearings after 75K miles will stop TBF and/or the driveshaft creep/forward push on the front flexplates?

Constantine
Old 03-10-2005, 11:13 PM
  #52  
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Constantine will you please keep thinking along those lines? An innovative thinker like yourself is bound to come upon a way to make this work.
Originally Posted by Constantine
Hi Erkka,

My very first TBF fix was a sliding coupler mounted to custom made flexplates. Problem was the vibration from the drivetrain caused it to rattle within itself. Very noisy but got quieter with higher RPM.

After much thought and designing a brand new torque tube assembly on paper, I figured the product would be very exspensive for anyone to buy one. So I looked at this whole problem again and devised this clamp set up. If you study the manuals you can see Porsche did not want a hint of forward pressure at the front flexplates.

Regards,
Constantine
Old 03-10-2005, 11:34 PM
  #53  
borland
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Constantine,

I also want to add that reducing the cost to $150 would result in hundred or so sold per year compared with only a few at $375. So your net profit would actually be higher.

Just speaking from my personal experience as a fully employed as a professional engineer for over 30 years with engineering design experience on mechanical systems as well as a lifetime of working on my own cars, including replacing the TT and converter bearings.

I actually lubricated my splines with moly grease upon assembly, but have had no detectable movement with the factory recommended pinch bolt torque. The 75K is based on what I estimate from car's service records and what I've read here. The earlier cars with the smaller shaft and circlip can probably go much longer.
Old 03-11-2005, 07:12 AM
  #54  
Black Sea RD
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Hi Borland,

First, if you saw the new clamp you would see the price of $350-$375 is actually very good for what it is. Lots of machining, metal, and treating, no way to make it for $150.

The research I've done does not indicate rebuilding the TT and replacing the torque converter bearings has any effect on the forward push at the front flexplates.

As for lubricating the splines and not having the driveshaft creep many others have seen, good for you! You are in the minority.

Kind regards,
Constantine

Originally Posted by borland
Constantine,

I also want to add that reducing the cost to $150 would result in hundred or so sold per year compared with only a few at $375. So your net profit would actually be higher.

Just speaking from my personal experience as a fully employed as a professional engineer for over 30 years with engineering design experience on mechanical systems as well as a lifetime of working on my own cars, including replacing the TT and converter bearings.

I actually lubricated my splines with moly grease upon assembly, but have had no detectable movement with the factory recommended pinch bolt torque. The 75K is based on what I estimate from car's service records and what I've read here. The earlier cars with the smaller shaft and circlip can probably go much longer.



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