Could someone explain to me what the difference is between a balanced crank and a dynamically balanced crank or is it the same thing just with a fancy name ?
Chris.
Dynamically balanced crank
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firestorm996
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Errr, it's more expensive 
to get it dynamically balanced.
Dynamic is better so I have been told as (as is Firestorm996's VTR - one of my engines) the pistons/rings/small end and rods and big-end shells are all weight matched. Then a weight is made to the exact weight of the above. This is fixed to the crank pin, evething else is put on too, both end of the crank and then it is all balanced to with in 0.02oz (think it's 0.02) whilst spinning and all together, ker ching ££££
I'll ask him when I see him next and get the full story.
Before I get it done I did find a website that explained it all and nascar engines are balanced dynamically as above.
Del.
to get it dynamically balanced.Dynamic is better so I have been told as (as is Firestorm996's VTR - one of my engines) the pistons/rings/small end and rods and big-end shells are all weight matched. Then a weight is made to the exact weight of the above. This is fixed to the crank pin, evething else is put on too, both end of the crank and then it is all balanced to with in 0.02oz (think it's 0.02) whilst spinning and all together, ker ching ££££
I'll ask him when I see him next and get the full story.
Before I get it done I did find a website that explained it all and nascar engines are balanced dynamically as above.
Del.
Sirch345: to answer your question I guess basically, you are talking about the same thing, a balanced crank.
There are two balancing methods used for various purposes:
1. Static balancing - usually used on large slow rotating objects, such as large propellers for aircraft. Heavier blade falls to the lowest point etc etc.
2. Dynamic Balancing - where the component is rotated and the amount of unbalance is measured on planes.
My guess is it would be impossible to statically balance a V crankshaft, incidentally, it's quite difficult to dynamic balance a V Crankshaft too, as Del correctly said a mass is attached to the big ends which is a proportion of the weight of the con rod, small end, piston & rings. The proportion depends upon the angle of the V.
An inline engine it's just a case of balancing the crank on it's own and removing material from the heavier side of the crank.
I hope that helps.
There are two balancing methods used for various purposes:
1. Static balancing - usually used on large slow rotating objects, such as large propellers for aircraft. Heavier blade falls to the lowest point etc etc.
2. Dynamic Balancing - where the component is rotated and the amount of unbalance is measured on planes.
My guess is it would be impossible to statically balance a V crankshaft, incidentally, it's quite difficult to dynamic balance a V Crankshaft too, as Del correctly said a mass is attached to the big ends which is a proportion of the weight of the con rod, small end, piston & rings. The proportion depends upon the angle of the V.
An inline engine it's just a case of balancing the crank on it's own and removing material from the heavier side of the crank.
I hope that helps.
BazilD
Sometimes you're the bug, and sometimes you're the windscreen!
Sometimes you're the bug, and sometimes you're the windscreen!