Ritech Flex Plate Clamp - The New & Complete answer to TBF
10-16-2014, 02:26 PM
#16
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Just think if they'd spec'd something like the 968 clamp.
(I'm putting this one in my '88 manual along with a shiny new stub - same size as the multi-piece unit.)
10-16-2014, 03:00 PM
#17
Captain Obvious
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Has there been any reports of shaft migration using the Super Clamp? I don't think it has. Maybe Ken is riggt and the OE clamp is the problem.
10-16-2014, 03:30 PM
#19
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The stock clamp just needs a bit of help. (Single-sided clamps not being all that strong.)
The shaft doesn't migrate after installing a PKlamp (which Roger still sells, BTW
).
This new one is a more elegant solution but does the same thing, along with additional clamping on the shaft itself to limit any rearward movement.
The stock clamp is just along for the ride, here.
The shaft doesn't migrate after installing a PKlamp (which Roger still sells, BTW
).This new one is a more elegant solution but does the same thing, along with additional clamping on the shaft itself to limit any rearward movement.
The stock clamp is just along for the ride, here.
10-16-2014, 04:16 PM
#20
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There's more to the story.
And I've mentioned this, in a prior thread....
I disassemble engines....lots of them...from lots of different 928 models.
Engines with an "added" clamps show accelerated wear on the front side of the thrust bearing.
That tells me that the shaft, even though clamped securely and not able to pull out of the flexplate when an additional clamp is installed, is still "over twisting" and pulling the crankshaft to the rear.
Unlike the problem when the flexplate gets crushed into the flywheel (from the clamp slipping) and there being constant high loading on the flexplate (and thus the rear of the thrust bearing), the contact with the front side of the thrust bearing may not be as significant of an issue.
However, in my mind, it does point to the real cause of the problem and requires some further research.
And that "high loading" is going to reduce the power output of the engine....not to mention that this load is "pulling" the crankshaft in the opposite direction than it wants to travel (under acceleration) and loading the rods against their thrust surfaces.
And I've mentioned this, in a prior thread....
I disassemble engines....lots of them...from lots of different 928 models.
Engines with an "added" clamps show accelerated wear on the front side of the thrust bearing.
That tells me that the shaft, even though clamped securely and not able to pull out of the flexplate when an additional clamp is installed, is still "over twisting" and pulling the crankshaft to the rear.
Unlike the problem when the flexplate gets crushed into the flywheel (from the clamp slipping) and there being constant high loading on the flexplate (and thus the rear of the thrust bearing), the contact with the front side of the thrust bearing may not be as significant of an issue.
However, in my mind, it does point to the real cause of the problem and requires some further research.
And that "high loading" is going to reduce the power output of the engine....not to mention that this load is "pulling" the crankshaft in the opposite direction than it wants to travel (under acceleration) and loading the rods against their thrust surfaces.
10-16-2014, 04:22 PM
#21
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Good to see another option available- I think the total now runs at 5 systems [including my currently deployed option utilising Loctite.
Not that I have seen that many examples of clamp failure [about 8 cases] but the only motor that survived was my S4 motor and that because of my intervention through this list
It seems that TBF failure occurs in the region of 60k km to 120k km. The clamp slips because it cannot apply sufficent force to hold thejoint so the logical question has to be what has degraded to permt the slippage to occur? The only logical explanation I can reason is that some kind of crevice corrosion may be taking place- nothing too obvious that you can visually see/easily but maybe just enough to reduce the area of contact and thus the effective clamp tension.
When my S4 drive shaft failed I fitted a new drive shaft to the used [70k km clamp] and it would not hold so this makes me think the clamp is possibly the problem child. Personally I have never heard of a very low mileage failure of this kind.
Applying the Loctite effectively fill the voids and [possibly?] acts as a seal to prevent crevice corrosion taking place. Either way it has served me well for some 100k km of useage with my S4 motor in my S4 and the last 7 years with this motor in my GTS chassis.
Any solution that increases the effective clamping force is a good solution providing it holds, Constantine's clamp is mechanically speaking the most elegant [my opinion] solution. The Loctite solution increases the contact patch surface area so more total clamping force is available for the same applied torque on the tensioning bolt [the cheapest solution].
As I can tell Richard's clamp, another imaginitive piece of engineering, acts as a back up that mechanically holds the clamp to the shaft independent of the status of the clamp to shaft contact.
Ultimately the only thing that matters is the ability of whatever system is used to hold the shaft with no slippage whatsover. Anyone who runs the auto tranny without one of these enhancements is tempting fate [foolish?] to say the least.
Regards
Fred
Not that I have seen that many examples of clamp failure [about 8 cases] but the only motor that survived was my S4 motor and that because of my intervention through this list
It seems that TBF failure occurs in the region of 60k km to 120k km. The clamp slips because it cannot apply sufficent force to hold thejoint so the logical question has to be what has degraded to permt the slippage to occur? The only logical explanation I can reason is that some kind of crevice corrosion may be taking place- nothing too obvious that you can visually see/easily but maybe just enough to reduce the area of contact and thus the effective clamp tension.
When my S4 drive shaft failed I fitted a new drive shaft to the used [70k km clamp] and it would not hold so this makes me think the clamp is possibly the problem child. Personally I have never heard of a very low mileage failure of this kind.
Applying the Loctite effectively fill the voids and [possibly?] acts as a seal to prevent crevice corrosion taking place. Either way it has served me well for some 100k km of useage with my S4 motor in my S4 and the last 7 years with this motor in my GTS chassis.
Any solution that increases the effective clamping force is a good solution providing it holds, Constantine's clamp is mechanically speaking the most elegant [my opinion] solution. The Loctite solution increases the contact patch surface area so more total clamping force is available for the same applied torque on the tensioning bolt [the cheapest solution].
As I can tell Richard's clamp, another imaginitive piece of engineering, acts as a back up that mechanically holds the clamp to the shaft independent of the status of the clamp to shaft contact.
Ultimately the only thing that matters is the ability of whatever system is used to hold the shaft with no slippage whatsover. Anyone who runs the auto tranny without one of these enhancements is tempting fate [foolish?] to say the least.
Regards
Fred
10-16-2014, 05:33 PM
#22
Rennlist Member
If there are forces that pull and push the driveshaft as Greg says, under different circumstances, then to me a "sliding coupler" would seem to be the best solution, such that the driveshaft could move fore and aft a little. This was mentioned by someone else in another thread as being the system used in jet engines.
Are there any reasons why this would not work on the Porsche drivelines?
Are there any reasons why this would not work on the Porsche drivelines?
10-16-2014, 05:38 PM
#23
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Following Greg's line of thought I am glad I got a NEW (not clean used) driveshaft when I had my TT rebuilt by Constantine. Have his Super Clamp too.
10-16-2014, 06:10 PM
#24
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Again the two biggest selling points of this clamp design is that it goes one stage further than anything else currently on the market and ensures there is no movement possible at all. As already said clamping on its own is not enough so Richard wanted to take it beyond the pure clamping force of the "Superclamp".
The same and possibly more clamping force than a "Superclamp".
The additional mechanical ability to prevent any movement of the torque shaft - period. No other clamp does that!!!
And here is the "Icing on the Cake" you do not have to REMOVE the TT & Gearbox to fit it.
The same and possibly more clamping force than a "Superclamp".
The additional mechanical ability to prevent any movement of the torque shaft - period. No other clamp does that!!!
And here is the "Icing on the Cake" you do not have to REMOVE the TT & Gearbox to fit it.
__________________
Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
George Layton March 2014
928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
George Layton March 2014928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
10-16-2014, 08:37 PM
#25
Former Sponsor
Again the two biggest selling points of this clamp design is that it goes one stage further than anything else currently on the market and ensures there is no movement possible at all. As already said clamping on its own is not enough so Richard wanted to take it beyond the pure clamping force of the "Superclamp".
The same and possibly more clamping force than a "Superclamp".
The additional mechanical ability to prevent any movement of the torque shaft - period. No other clamp does that!!!
And here is the "Icing on the Cake" you do not have to REMOVE the TT & Gearbox to fit it.
The same and possibly more clamping force than a "Superclamp".
The additional mechanical ability to prevent any movement of the torque shaft - period. No other clamp does that!!!
And here is the "Icing on the Cake" you do not have to REMOVE the TT & Gearbox to fit it.
Nice!
10-16-2014, 08:59 PM
#26
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Again the two biggest selling points of this clamp design is that it goes one stage further than anything else currently on the market and ensures there is no movement possible at all. As already said clamping on its own is not enough so Richard wanted to take it beyond the pure clamping force of the "Superclamp".
The same and possibly more clamping force than a "Superclamp".
The additional mechanical ability to prevent any movement of the torque shaft - period. No other clamp does that!!!
And here is the "Icing on the Cake" you do not have to REMOVE the TT & Gearbox to fit it.
The same and possibly more clamping force than a "Superclamp".
The additional mechanical ability to prevent any movement of the torque shaft - period. No other clamp does that!!!
And here is the "Icing on the Cake" you do not have to REMOVE the TT & Gearbox to fit it.
As far as the other theories being discussed about the drive shafts, I also don't agree with them from our research done about TBF and when having our new drive shafts made.
We already have a design on paper for a sliding coupler, but it is costly and includes new drive shafts and a new flex plate coupler. We haven't gone through with making it since we really don't see where it would make fiscal sense to get it all made.
Have fun,
10-16-2014, 09:07 PM
#28
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Sorry, but I take exception to this line. This new clamp does not operate by superior clamping, it does so by limiting the rearward travel of the drive shaft.
As already said superior clamping on its own is not the answer - hence the new design. I do not sell your Superclamp I sell the PKlamp and the Ritech clamp to cover ALL needs. Competition is always good if not welcome.
10-16-2014, 09:13 PM
#29
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In the picture showing half the clamp placed onto the drive shaft and OE clamp, it seems there is a very specific cutout to allow for the OE clamp and the rear of the drive shaft as it sticks out of the rear of the OE clamp. The cutout seems to limit the rearward travel of the drive shaft by the interference of the spline bump at the rear of the spline.
We have noticed that the amount of splines showing at the rear of the OE clamp varies when setting the float of the flywheel/crank off the engine's thrust bearing.
How would this new clamp allow for this variance of spline length at the rear of the OE clamp?
We have noticed that the amount of splines showing at the rear of the OE clamp varies when setting the float of the flywheel/crank off the engine's thrust bearing.
How would this new clamp allow for this variance of spline length at the rear of the OE clamp?
10-16-2014, 09:34 PM
#30
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Yes - this is a free World (I Think) and you as well as everybody else is entitled to there opinion.
As already said superior clamping on its own is not the answer - hence the new design. I do not sell your Superclamp I sell the PKlamp and the Ritech clamp to cover ALL needs. Competition is always good if not welcome.
As already said superior clamping on its own is not the answer - hence the new design. I do not sell your Superclamp I sell the PKlamp and the Ritech clamp to cover ALL needs. Competition is always good if not welcome.
And the reason your not selling our products is because no one is selling them besides ourselves, hence our Rennlist Small Business Partner banner.
Cheers,