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Re: School me on center counter weighted cranks [Re: Dragula] #2622490
02/17/19 11:42 AM
02/17/19 11:42 AM
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polyspheric Offline
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I see i've exceeded the audience's attention span... again.
I'll try to use more slang and fewer facts in future.

the counter weights where offset to help longevity for high RPM
I leave mine home to save weight.


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Re: School me on center counter weighted cranks [Re: Dragula] #2622509
02/17/19 01:15 PM
02/17/19 01:15 PM
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Charlotte, North Carolina
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Why is expensive Mallory weight always added to a crankshaft counterweight? Why couldn't the underside of a piston or the bottom of a rod cap be lightened instead? The trick is to keep it as light as possible, isn't it? Why keep adding weight? I see this on tires in the dealership. People that have had their tires balanced several times in their life. Some come in with weights all over the inside of the rim. We all know that this is laziness on the part of the tech balancing the tires. Can the same be said for crank balancing?

Re: School me on center counter weighted cranks [Re: sgcuda] #2622551
02/17/19 03:24 PM
02/17/19 03:24 PM
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Originally Posted By sgcuda
Why is expensive Mallory weight always added to a crankshaft counterweight? Why couldn't the underside of a piston or the bottom of a rod cap be lightened instead? The trick is to keep it as light as possible, isn't it? Why keep adding weight? I see this on tires in the dealership. People that have had their tires balanced several times in their life. Some come in with weights all over the inside of the rim. We all know that this is laziness on the part of the tech balancing the tires. Can the same be said for crank balancing?


If you are adding weight to a counter weight, it's because it's too light. You can't take that much out of a rod cap or a piston unless the piston is junk. Let's say all you need is 15-20 grams of Mallory. You ain't going to find that much weight to remove between the rods and the Pistons unless they are just flat out garbage.


Just because you think it won't make it true. Horsepower is KING. To dispute this is stupid. C. Alston
Re: School me on center counter weighted cranks [Re: polyspheric] #2622577
02/17/19 04:33 PM
02/17/19 04:33 PM
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Originally Posted By polyspheric
I see i've exceeded the audience's attention span... again.
I'll try to use more slang and fewer facts in future.

the counter weights where offset to help longevity for high RPM
I leave mine home to save weight.


Maybe less emphasis of your college degree would be more helpful.... if you actually do have an understanding of that which you speak.

long on words indicates a shortage of understanding.


'86 Maple Grove KOS Mopar low qualifier......true street legal with no power adders.

NOS-used when losing since 1940.

Re: School me on center counter weighted cranks [Re: Dragula] #2622608
02/17/19 05:35 PM
02/17/19 05:35 PM
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polyspheric Offline
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What a rude little boy you are. You asked the same question several times, but are unable to understand that there is no definitive answer: you're responsible for your own decisions.
Which "college degree" are you referring to?
Incomplete comprehension indicates a shortage of intelligence.


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Re: School me on center counter weighted cranks [Re: madscientist] #2622612
02/17/19 05:40 PM
02/17/19 05:40 PM
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Originally Posted By madscientist
Originally Posted By sgcuda
Why is expensive Mallory weight always added to a crankshaft counterweight? Why couldn't the underside of a piston or the bottom of a rod cap be lightened instead? The trick is to keep it as light as possible, isn't it? Why keep adding weight? I see this on tires in the dealership. People that have had their tires balanced several times in their life. Some come in with weights all over the inside of the rim. We all know that this is laziness on the part of the tech balancing the tires. Can the same be said for crank balancing?


If you are adding weight to a counter weight, it's because it's too light. You can't take that much out of a rod cap or a piston unless the piston is junk. Let's say all you need is 15-20 grams of Mallory. You ain't going to find that much weight to remove between the rods and the Pistons unless they are just flat out garbage.


But the same 15-20 grams split between 8 pistons and 8 rods might be doable. Does anyone actually know the relationship between rod/piston weight relative to where 1 weight is added to a crankshaft?

Re: School me on center counter weighted cranks [Re: Dragula] #2622666
02/17/19 08:08 PM
02/17/19 08:08 PM
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New York
polyspheric Offline
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For this method, in a V8 with 90° bank angle, the relationship: balance weight = 100% of rotating mass + 50% of reciprocating mass. Other engines vary all over the map.

Not that easy.
A connecting rod has, by popular convention, its weight divided into reciprocating (top) and rotating (bottom) components. The line of division is the center of gravity.
Missing from this equation: a really long rod (3:1 ratio) has most of its reciprocating thrust in the vertical plane, a short rod (1.3:1) has a far larger horizontal component.
Conventional balancing completely ignores this (but it's critical to motorcycle engines).


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Re: School me on center counter weighted cranks [Re: polyspheric] #2622669
02/17/19 08:13 PM
02/17/19 08:13 PM
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Originally Posted By polyspheric
What a rude little boy you are. You asked the same question several times, but are unable to understand that there is no definitive answer: you're responsible for your own decisions.
Which "college degree"(that explains a lot) are you referring to?
Incomplete comprehension indicates a shortage of intelligence.


Son, Incomprehensive explanation indicates a shortage of intelligence.

Last edited by Harry's Taxi 2; 02/17/19 08:17 PM.
Re: School me on center counter weighted cranks [Re: Dragula] #2622748
02/18/19 12:02 AM
02/18/19 12:02 AM
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New York
polyspheric Offline
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You didn't find a complete answer to your question in my statement?
Not my job.


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Re: School me on center counter weighted cranks [Re: Dragula] #2622778
02/18/19 01:01 AM
02/18/19 01:01 AM
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Man, I hate it when it's cold outside. Everybody gets all testy lol.

The long and short of it is this. You typically only find center weights on expensive cranks, designed by smart folks. Bryant, and winberg to me are top of the heap of the stuff we all use. They have suggested them for one application, and recommended against in others. So if you're wondering how to order your 3 to 5 thousand dollar crank, either of those shops will shoot you straight without any regard for making more money. A benefit of dealing with top, established shops that really care about reputation, and quality.

Re: School me on center counter weighted cranks [Re: Dragula] #2622863
02/18/19 12:02 PM
02/18/19 12:02 PM
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NE Ohio
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I can answer that question .................

Which "college degree" are you referring to? - "I’m entirely self-taught, and have no professional engineering or technical training."

Re: School me on center counter weighted cranks [Re: Dragula] #2622873
02/18/19 12:30 PM
02/18/19 12:30 PM
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New York
polyspheric Offline
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Translation: "I didn't sit in a room while someone read prepared text to me until I could repeat it".
Anyone have a different description for a degree? Hint: none of them involve getting under a car, do they?


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Re: School me on center counter weighted cranks [Re: dthemi] #2622874
02/18/19 12:31 PM
02/18/19 12:31 PM
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Originally Posted By dthemi
Man, I hate it when it's cold outside. Everybody gets all testy lol.

The long and short of it is this. You typically only find center weights on expensive cranks, designed by smart folks. Bryant, and winberg to me are top of the heap of the stuff we all use. They have suggested them for one application, and recommended against in others. So if you're wondering how to order your 3 to 5 thousand dollar crank, either of those shops will shoot you straight without any regard for making more money. A benefit of dealing with top, established shops that really care about reputation, and quality.


Thanks Dt Hemi for some real world insight on a interesting subject



"Just a Bracket car dressed up like a streetcar"
Re: School me on center counter weighted cranks [Re: polyspheric] #2622963
02/18/19 04:29 PM
02/18/19 04:29 PM
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Bend,OR USA
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Originally Posted By polyspheric
Translation: "I didn't sit in a room while someone read prepared text to me until I could repeat it".
Anyone have a different description for a degree? Hint: none of them involve getting under a car, do they?

That sounds exactly like some of the electrical engineers I had to deal with while working for the telephone company that knew nothing about customer service or dealing with them runaway


Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
Re: School me on center counter weighted cranks [Re: Dragula] #2622970
02/18/19 04:49 PM
02/18/19 04:49 PM
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Las Vegas
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UGH...Never gonna understand why some folks get so butthurt over some of this stuff.

As for the question at hand. A center counter weighted crank is always better IF it is needed for your application..


"I am not ashamed to confess I am ignorant of what I do not know."

"It's never wrong to do the right thing"
Re: School me on center counter weighted cranks [Re: Dragula] #2623013
02/18/19 06:35 PM
02/18/19 06:35 PM

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So what would be the applications for a Center counter weighted crank?

Re: School me on center counter weighted cranks [Re: ] #2623073
02/18/19 09:58 PM
02/18/19 09:58 PM
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Frostbitefalls MN (Rocky&Bullw...
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Originally Posted By Superfreak
So what would be the applications for a Center counter weighted crank?
high rpm, high HP, to save/add life to a stock block.


8..603 156 mph best, 2905 lbs 549, indy 572-13, alky
Re: School me on center counter weighted cranks [Re: Dragula] #2623248
02/19/19 11:30 AM
02/19/19 11:30 AM
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MI, usa
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$3000 crank in a stock block? Seems backwards to me.
Doug

Re: School me on center counter weighted cranks [Re: dvw] #2623348
02/19/19 03:25 PM
02/19/19 03:25 PM
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Frostbitefalls MN (Rocky&Bullw...
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Originally Posted By dvw
$3000 crank in a stock block? Seems backwards to me.

Doug,after cracking one $800 crank in 100 runs, and chewing up the maincaps in my nice new megablock back in 05, i spent 2300 for a Crower ccw. I figure guys that are somewhat commited to stock blocks might find it and reasonable alternative if it doubles or triples the life of thier block. A busted block also means a lost race and or weekend, all that machinework and parts, and block cores that are getting tougher to find.


8..603 156 mph best, 2905 lbs 549, indy 572-13, alky
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