Drilled Crank Thoughts...
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01-09-2008, 05:14 PM
#228
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Quick question about those pictures Kevin.
How are they backwards?
I was under the impression that you wanted to match the serial numbers like you see in picture 2.
How are they backwards?
I was under the impression that you wanted to match the serial numbers like you see in picture 2.
01-09-2008, 05:42 PM
#229
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Actually Kevin you have no idea what you are talking about...the assembled rod /cap is machined and the surfaces you see are meaningless the numbers are matched as shown.....Try again to explain the failure...because this time you are SOOOO WRONG !
01-09-2008, 05:43 PM
#230
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Why would the misalignment of the cap trump the serial numbers. Don't the serial number signify the orientation of the caps when the bearing surfaces were machined. I'm not saying you are wrong I just find it odd that the rod people would have screwed up the marking of the rod caps.
Dangit: those 928 Intl people are just too fast and too good.
Dangit: those 928 Intl people are just too fast and too good.
01-09-2008, 05:53 PM
#231
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It is pretty easy when you can walk 50 feet into the warehouse and look at 5 or 6 rods and see that the " misalignment " has NOTHING to do with how the big end hole is machined....
01-09-2008, 06:33 PM
#232
Drifting
bloody turks eh? seems ahmed was stationed to install all the 2/6 bearing caps for porsche 928 engines, silly fool, he was on the wrong side of the engine so he wouldnt use his left hand...
01-09-2008, 06:46 PM
#233
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Nice anecdote but the point remains that the surfaces you were looking at were machined before the caps were joined to the rods and the FINAL machining of the bearing hole and shoulders was done assembled .....guess again. Also worth noting that the rods are NOT semetrical and if the cap were "reversed" would not fit the bearing journal.
01-09-2008, 06:53 PM
#234
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Nice anecdote but the point remains that the surfaces you were looking at were machined before the caps were joined to the rods and the FINAL machining of the bearing hole and shoulders was done assembled .....guess again. Also worth noting that the rods are NOT semetrical and if the cap were "reversed" would not fit the bearing journal.
01-09-2008, 06:59 PM
#235
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By the way, my thinking is comparing a Chrysler operation to Porsche is unreasonable. Weren't 928s hand built as opposed to an assembly line process?
01-09-2008, 07:08 PM
#236
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2mm wider to be precise. Or more specifically on one side 2mm was machined away to make lower end nonsymmetric and make crank lenght 8x2mm=16mm shorter.
01-09-2008, 07:33 PM
#237
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Sucks being at work and missing all this good stuff!
Dave, I read your description and did not see any mention of a drilled crank. Did your engines have a drilled crank by the favored machine shop installed in them? I believe Mark A. had installed a drysump system without drilling his crank and had 2/6 bearing failure. After crank drilling the 2/6 failure was solved for him.
Constantine
Dave, I read your description and did not see any mention of a drilled crank. Did your engines have a drilled crank by the favored machine shop installed in them? I believe Mark A. had installed a drysump system without drilling his crank and had 2/6 bearing failure. After crank drilling the 2/6 failure was solved for him.
Constantine
Two summers ago I lost a fresh 4.7 engine on the track at Portland International. That engine had a full Kevin Johnson windage tray and crank scraper and was running Mobil 1. Last September I lost another 4.7, this time with no scraper, but WITH AMSOIL and an improved breather. Neither engine was run past 6K rpm. Both happened within the first hour of tracking. On both, the 2/6 rod bearing failed.
The new engine will have a dry sump, improved breather, Accusump, and drilled crank and all the mojo I can muster.
Regarding the 300+ preceding pages of discussion, there is NO proof of anything anywhere, except that these engines regularly burn up their 2/6 rod bearings. Virtually nothing else has failed. I'm concentrating on the care and feeding of my 2/6 rod bearings because it would appear that that is the only way I'm going to get any track time.
And if this one fails, I won't need to get another Chevy drilled crank because the next engine will be a Chevy.
Dave
The new engine will have a dry sump, improved breather, Accusump, and drilled crank and all the mojo I can muster.
Regarding the 300+ preceding pages of discussion, there is NO proof of anything anywhere, except that these engines regularly burn up their 2/6 rod bearings. Virtually nothing else has failed. I'm concentrating on the care and feeding of my 2/6 rod bearings because it would appear that that is the only way I'm going to get any track time.
And if this one fails, I won't need to get another Chevy drilled crank because the next engine will be a Chevy.
Dave
01-09-2008, 08:42 PM
#238
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Again you do not know what you are looking at. What matters is the hole through the rod where the bearing fits not the alignment of the sides of the ends of the rod and caps which do not touch anything. And again the offset of the shoulders makes flipping the cap around IMPOSSIBLE ....try that scenerio.
