Re: alfa-digest V7 #630 - Restrictors in the oil passages

[AlfaNeely@domain.elided]

In a message dated 4/13/99 7:02:09 PM Central Daylight Time, simon@domain.elided 
writes:

<< Subj:	 Re: alfa-digest V7 #630 - Restrictors in the oil passages
 Date:	4/13/99 7:02:09 PM Central Daylight Time
 From:	simon@domain.elided (Simon Favre)
 To:	AlfaNeely@domain.elided
 CC:	alfa-digest@domain.elided (Alfa Digest)
 
 I think we're talking in different languages. ;=)
 <snip>
 I was not suggesting grinding grooves in the crank. I was talking about the
 bores in the block, but that may be a useless idea.
 <snip>
 >         I am not sure what you mean by a "redundant" oil passage.  The four
 > cylinder Alfa crank is drilled with six holes capped by the infamous 
aluminum
 > plugs.  One hole goes from the number 1 rod bearing throw to the number 1
 > main.  The second goes from the number 1 rod through main number 2 and 
stops
 > in the middle of rod bearing number 2.  The third goes from number 2 rod to
 > number 3 main.  The rest of the crank is a mirror image of the front half 
and
 > I will ignore it for this discussion.
 
 If you have oil coming into #2 and #4 mains from the new holes in the block 
 via the drilled bearing shells, then perhaps the oil passages in the crank
 that fed #2 and #4 are redundant. It depends on your point of view, I guess. 
 ;=)

 This is where I was trying to ask a question. I guess I was confused about
 the shape of the bearing shell. If the grooved shells don't require a groove
 in the block bore, then it sounds like a viable option. Is grooving standard
 shells an option?
  
 It's definitely more interesting than cupholders.
 
 Ciao,
 
 Simon
  >>
	We are speaking the same language, just using it different.  To me 
the journal is on the crankshaft.  I seem to recall Hot Rod Magazine cutting 
oil grooves in the crank, however, I agree with  bearbvd@domain.elided (Greg 
Hermann) when he says,
 
<< Not only no, but #%$ NO!! This would create a stress concentration in the
 crank, and be VERY undesireable. The classic approach is to "cross-drill"
 the crank--drill two holes at 90 degrees to each other clear through the
 journals>>
 
	I looked at an Alfa block and the bearings ready to go in it.  The 
factory did groove the block so that oil circulates all around the back side 
of the three main bearings supplied with factory oiling.  The three wider 
bearings also have four oil holes to feed from the oil supply behind the 
bearing shell.  I did not do this on the two mains I had drilled.  I just 
have one hole feeding the groove in the bearing surface.  I do not know if 
the additional oil capacity would be useful or not.
	Alfa is amazing sometimes.  They go to all the trouble to supply 
plenty of oil to three of the main bearings and supply almost none to the 
other two.  It is almost as if the two narrow mains are just along for the 
ride.  But they do spin bearings without extra oil.
	Having a set of bearings grooved is possible.  I just shopped until I 
found some already done.  The set I ordered from Centerline did not have 
grooves in all bearings and I had to return them as none of the 0.010 under 
sets they had in stock had that feature.  The bearings I am ready to put in 
came from IAP.  They are "Bimet" manufactured by Trioneuro.  Never heard of 
them, but they look fine and are fully grooved on the mains.  The matching 
rod bearings are not grooved at all.

	OK, I have my tax return done six months and one day before I have 
to.  I promised my wife no extension this year.  I am off to read the article 
on the art of engine balancing in the May 99 Hot Rod Magazine.  Tomorrow 
night, it is back to the garage, at long last!  Tax season is taxing for a 
CPA and procrastination by constant checking of e mail is too tempting.  
Maybe I will go weld a cup holder to the cage in my race car. 
Ciao,
Russ Neely
Oklahoma City

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