Molnar crank on balancer

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Oldmanmopar

Going left turning right
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Here are some pictures of a Molnar crank on a balancer and the weight removed from the outer diameter. also the print of the 8 spins after cuts. It will get more cuts to get it closer. Check the videos in the next post.

Also I posted pictures of a molnar and a scat here with motors built elsewhere. Check out the holes they drilled. One of the holes with the flashlight in shows the drill hit one another. One crank is from Jensen machine. Can you say vibration

Then look how he reduced the holes and depth by cutting the diameter in the next post videos of the computer graph. When he is done there will be barely any hole drilled. Torque out the gazoo with way less outer reciprocating weight. The last picture is the crank for our small block

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Are most cranks drilled during balancing because it is less expensive or that they do not have the machinery to cut the OD down? Seems to me the later is the prefered method. Thanks for sharing info and pictures.
 
4 deep holes in both counter weights. Read the graph



After taking .100 off the counterweights. 1 hole in each. Now cut a little more until the hole gets shallow. Then finish balance it .

 
Are most cranks drilled during balancing because it is less expensive or that they do not have the machinery to cut the OD down? Seems to me the later is the prefered method. Thanks for sharing info and pictures.
It takes less time to drill holes. Also the cranks are very hard and take carbide cutters to cut them. Cutting the OD also cuts down on windage. . That crank was taken out of the balancer 8 times and put in the lathe 8 times and its not done. You can see on the graph in the first post the change with every cut up to 8. I'll repost the the rest of the balance and cuts. I just walked down and he was closing up for the day at 7:30 pm.
 
That looks like something on the Winberg Cranks website. Awesome looking work!
 
I have been curious how much oil clinging to rods/pistons/crank throws messes with the balance when a motor is running...
 
I have been curious how much oil clinging to rods/pistons/crank throws messes with the balance when a motor is running...
They put equal in truck tires to balance them so would it effect balance? Only the crank would know.

But they also make crank scrapers and dry sumps. Everyone would have a different opinion on that question.

I say keep the oil from being picked up by the crank for performance reasons and to keep the oil in the pan for oiling reasons. Our race block is also made to keep the oil from returning down the center over the cam or crank. There are holes to thread for plugs. It flows around the reciprocating masses. What would have been the reason for that? They even sealed off the oil pump drive gear area,

Here are pictures of our race blocks, Newer Resto R3 and an old X block. Note the closed valley on the new block. There is a reason for this?

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Do you have any pictures of how he mills the relief into the crank counterweights and then cuts it into that beautiful wing shape? Curious to see the fixturing it takes to do that work.
 
Just imagine trying to throw water into a fan that's blowing 'at you' except now flatten the blade. I don't have the right word for it but when that crank is spinning there is a force field let's just say around it of windage that is pushing any and everything off of it... to its outer edges...'get to rest of windage in a sec'
.what is definitely there , is oil coming against it as it rains down 'returns' and with G-Force kicking in.. yet still it instantly sheds everything to the outside. Why oil direction is important hence the use of better returns to the rear and scrapers and of course trays which not only do a bit of final directing tothe sump but also stifle any oil from being picked up like a semi truck flying by with trailer that about drags you with it..
the scraper is there to make sure we quickly shed the last bit of oil drug by the crank that the windage tray couldn't keep in the sump. Or even not quick enough to where there's still residual sitting in the tray with the amount raining down that is not given enough time as RPM increases versus drain back AND rod and main bearing leakage.

The cam bearings,rods, mains...all in th4 middle...so heres where dry sump pops in to say hi.
 
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Part 2.
As anything fluid..it will merge , converge and severe its relation faster with a narrowed/knife edge counter weight and to some micro extent drag less with it. Measurable? Idk. I'm not the one to ask at that point.lol
 
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Jeez, I wish my boss would get a balancer like that. We have old junk but it works
 
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