Question for the 928 engine building experts
#16
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Lifetime Rennlist
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The point I was trying to make is that on the flat journal surface oil does a good job off preventing metal to metal contact but on the shoulders of the thrust bearing it no longer pushes a wave of oil around the surface. The radial action tends to push out the lubricant as it escapes around the outer edges. Too much gap and too little lubrication and you get metal to metal. On the automatics the creep of the clamp on the torque tube leads to too much preload. With a 5 speed the action of the clutch pulls on the crank. On and off the throttle probably has little to do with loads on the thrust surfaces. But with any clutch it is best to shift to neutral as you approach a stop and let out the clutch as using the release bearing to hold out the clutch is an unnatural act to be avoided as much as possible.
#17
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Thread Starter
Greg,
I need a rich benefactor!
It would break my heart to sling a viable GTS crankshaft [were it such] but of course deep down I pretty much know that there is little to no prospect of me ever putting this unit back in a primary motor. Were it a spare motor- maybe. Alex's post was indeed very informative so gives me a reason to hang on to what I have just in case.
On the bright side my GTS crank must be "the mother of all paperweights" -
Regards
Fred
I need a rich benefactor!
It would break my heart to sling a viable GTS crankshaft [were it such] but of course deep down I pretty much know that there is little to no prospect of me ever putting this unit back in a primary motor. Were it a spare motor- maybe. Alex's post was indeed very informative so gives me a reason to hang on to what I have just in case.
On the bright side my GTS crank must be "the mother of all paperweights" -
Regards
Fred
#18
Former Vendor
Greg,
I need a rich benefactor!
It would break my heart to sling a viable GTS crankshaft [were it such] but of course deep down I pretty much know that there is little to no prospect of me ever putting this unit back in a primary motor. Were it a spare motor- maybe. Alex's post was indeed very informative so gives me a reason to hang on to what I have just in case.
On the bright side my GTS crank must be "the mother of all paperweights" -
Regards
Fred
I need a rich benefactor!
It would break my heart to sling a viable GTS crankshaft [were it such] but of course deep down I pretty much know that there is little to no prospect of me ever putting this unit back in a primary motor. Were it a spare motor- maybe. Alex's post was indeed very informative so gives me a reason to hang on to what I have just in case.
On the bright side my GTS crank must be "the mother of all paperweights" -
Regards
Fred
Making "custom" 928 parts is senseless. I know that and understand it. The market is very small and very limited in the number of people that want "the best".......even though they are dealing with one of the very best cars ever made. The "price point" for most custom 928 pieces is extremely low.....The lowest quality parts that could be made, out of the lowest quality metal, in the cheapest country on earth to make stuff is too expensive for the majority of 928 owners. The majority of "current" 928 owners want a "uber" car for less than $10,000.
I actually built "my GTS" crankshafts for several reasons:
1. There are a few people interested in increased performance from these engines.
2. A few of these people want quality parts.
3. Porsche will eventually run out of GTS crankshafts and I wanted to have an already tested option, ready to go.
4. GTS crankshafts are very heavy. I corrected this issue.
5. The "early" connecting rods are very weak and have very high bearing speeds. I corrected both of these issues.