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Almost Alive
Samba Member
Joined: October 12, 2009
Posts: 1345
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 Posted: Tue Feb 02, 2010 10:25 am Post subject: Full Circle Vs. Counter weighted Cranks |
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| What are the differences and what applications are they best suited for? |
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miniman82
Samba Swamp Donkey
Joined: March 22, 2005
Posts: 9515
Location: Southern Maryland
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| Posted: Tue Feb 02, 2010 12:35 pm Post subject: |
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Not his again... 
If you have to ask, you don't want to know.
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Build thread: http://www.thesamba.com/vw/forum/viewtopic.php?t=212747
| Glenn wrote: |
| satterley_sr wrote: |
I just wanted to bitch but I'm getting no sympathy. |
Welcome to the Samba. |
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saulverde
Samba Member
Joined: September 06, 2009
Posts: 162
Location: Alabama
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| Posted: Tue Feb 02, 2010 12:39 pm Post subject: |
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| I'm not a genius and have not and won't pretend like I have studied this topic. But I will give you a link to people who likely did. http://www.geneberg.com/cat.php?cPath=4_80 |
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Almost Alive
Samba Member
Joined: October 12, 2009
Posts: 1345
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| Posted: Tue Feb 02, 2010 12:54 pm Post subject: |
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Perfect. Thanks guys.
I did some searching and came up with nothing. That link helped a lot. |
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Alan_U
Samba Member
Joined: July 10, 2004
Posts: 1762
Location: Vancouver, BC Canada
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| Posted: Wed Feb 03, 2010 1:34 am Post subject: |
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I have both a welded full circle (made by DMS) and also a counter balanced welded from DPR.
Theory goes that the additional "cheeks" help make the crank more rigid. I've beat on my DMS crank and my mains in my mag case seemed to hold up extremely well especially the center bearing.
I will say the full circle by DMS makes my DPR "regular" counterbalanced crank light. The full circle apparently helps balance the crank more but it may just be a "mental" thing.
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No more time for VW's....... |
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miniman82
Samba Swamp Donkey
Joined: March 22, 2005
Posts: 9515
Location: Southern Maryland
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| Posted: Wed Feb 03, 2010 3:41 am Post subject: |
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Adding weight doesn't balance a crankshaft, balancing it does. This myth about FC cranks is ridiculous. 
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Build thread: http://www.thesamba.com/vw/forum/viewtopic.php?t=212747
| Glenn wrote: |
| satterley_sr wrote: |
I just wanted to bitch but I'm getting no sympathy. |
Welcome to the Samba. |
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Alan_U
Samba Member
Joined: July 10, 2004
Posts: 1762
Location: Vancouver, BC Canada
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| Posted: Wed Feb 03, 2010 8:59 pm Post subject: |
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| miniman82 wrote: |
| Adding weight doesn't balance a crankshaft, balancing it does. This myth about FC cranks is ridiculous. |
The weight is not the contributing factor for the advantages of full circle.
If you've ever looked at the DMS full circle you will see how the additional cheek helps make the crank rigid.
I see no fault in anyone investigating the option of full circle.
I would purchase a DMS full circle again if I needed another crank.
I would question "Genes" writings. I do not agree with all of his writings. IF all of his views were 100% accurate the world will come to an end and stop using synthetic oil. Not trying to disrespect Mr. Berg. I'm just pointing out that the new age has different views.
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11.92sec pump gas true daily driver. Who says it cant be done.
No more time for VW's....... |
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A.J.Sims
Banned
Joined: December 11, 2003
Posts: 1016
Location: LowBugget.com 982 N Batavia A4 Orange Ca 92867
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| Posted: Wed Feb 03, 2010 9:00 pm Post subject: |
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I like for 200 hp combos and lower a standered counter weighted crank but for 250hp I add a type 4 center, and 300hp I will go full circle. Based on lighten flywheels. Over 350hp start thinking flanged!
But with the subtracting weight from the flywheel then you might want to add some weight to a smaller circumference area, like the crank instead of the further out area of the flywheel! 
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miniman82
Samba Swamp Donkey
Joined: March 22, 2005
Posts: 9515
Location: Southern Maryland
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| Posted: Thu Feb 04, 2010 3:48 am Post subject: |
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| Alan_U wrote: |
| miniman82 wrote: |
| Adding weight doesn't balance a crankshaft, balancing it does. This myth about FC cranks is ridiculous. |
The weight is not the contributing factor for the advantages of full circle. |
You mention case saddle life though, which really has more to do with rotating assy balance quality than anything else. For proof, just look at how many completely stock cases get pounded out by normal driving. The stock non-cw crank does damage, but only because people tend to take the RPM's to places they ought not to go with stock engines. If crankshaft whip and weakness were the issue at high output, you'd almost certainly see the FC technique combined with flanged cranks. Stands to reason that if Moldex and others though it were a good idea, you'd see it more often. This is why it's such a debate, because there are so few that agree with its use.
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Build thread: http://www.thesamba.com/vw/forum/viewtopic.php?t=212747
| Glenn wrote: |
| satterley_sr wrote: |
I just wanted to bitch but I'm getting no sympathy. |
Welcome to the Samba. |
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Alan_U
Samba Member
Joined: July 10, 2004
Posts: 1762
Location: Vancouver, BC Canada
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| Posted: Thu Feb 04, 2010 7:57 pm Post subject: |
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Mini82,
No arguments or debates. I have no energy nor time to express what works for me.
If you look at DMS full circles they are not truly a full circle like many imagine. Would I buy one again? sure. Why did I buy a DPR counter weighted crank? just because.
Why haven't people purchased a dms full circle?? because its bad? Or they are too frugal to spend some extra coin? Is it an emotional decision?
I've compared my full circle beside a "normal" counter weighted. The center portion of the crank appears significantly beefy.
I see no negatives using either.
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Turbo_Manx_Maniac
Samba Member
Joined: December 05, 2004
Posts: 103
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| Posted: Fri Feb 05, 2010 11:03 am Post subject: |
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| If you look from a strength standpoint, cranks don't typically break at the center bearing, they break at the rod journal. Full circle does add strength to the larger cranks at the rod journal. |
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