Re: Rotating Assembly Weight Reduction
[Re: WILD BILL]
#626827
02/28/10 10:37 PM
02/28/10 10:37 PM
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Joined: Aug 2009
Posts: 2,076 Mooresburg, Tn
'72CudaRacer
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OP
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Quote:
Maybe that's why Scott and Dale did all my balancing on a day I wasn't there to help
I might be better off if he would just run me off...I know he would be! Can I watch??? Can I help??? Please??? Dan? Now, where did he go, again? HaHaHa.
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Re: Rotating Assembly Weight Reduction
[Re: Sport440]
#626828
03/01/10 11:46 AM
03/01/10 11:46 AM
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Joined: Oct 2007
Posts: 4,219 New York
polyspheric
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New York
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Herb Adams says a lot things. That approximation might have some merit - if referring to a specific radius of rotation. 1 lb. off the center of the crank does nothing. 1 lb. off the pin at 3.31" stroke does something. 1 lb. off the OD of a 440 counterweight does a whole lot more.
Boffin Emeritus
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Re: Rotating Assembly Weight Reduction
[Re: '72CudaRacer]
#626829
03/01/10 12:13 PM
03/01/10 12:13 PM
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Joined: Oct 2007
Posts: 4,219 New York
polyspheric
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Weight off pistons: 225 grams × 8 = 1800 grams reciprocating weight = 63.49 oz. Weight removed from crank for balance @ 50% factor: 900 grams rotating weight = 31.75 oz. Total weight off crank: 2700 grams = 95.24 oz. = 5.95 lbs. just for the pistons.
Weight off rod bearings: 4 grams × 8 = 32 grams rotating weight + 32 grams balance = -64 grams = 2.26 oz.
Rod weight loss: you added the 8 grams that you identified as a loss. In addition, we don't know how this was distributed.
Boffin Emeritus
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Re: Rotating Assembly Weight Reduction
[Re: emarine01]
#626831
03/01/10 06:11 PM
03/01/10 06:11 PM
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Joined: Jan 2003
Posts: 1,235 TN
65racer
2009 IHRA World Champion
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2009 IHRA World Champion
Joined: Jan 2003
Posts: 1,235
TN
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Brian, I shot you a PM, let me know if you got it, been having internet service problems Dave
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Re: Rotating Assembly Weight Reduction
[Re: polyspheric]
#626832
03/01/10 06:53 PM
03/01/10 06:53 PM
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Joined: Jan 2003
Posts: 6,591 Canton, Ohio
Sport440
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master
Joined: Jan 2003
Posts: 6,591
Canton, Ohio
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Quote:
Herb Adams says a lot things. That approximation might have some merit - if referring to a specific radius of rotation. 1 lb. off the center of the crank does nothing. 1 lb. off the pin at 3.31" stroke does something. 1 lb. off the OD of a 440 counterweight does a whole lot more.
totally! It was a approximation IMO, with No specifics to radius of rotation. As you state the further out, the better the effect. mike
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Re: Rotating Assembly Weight Reduction
[Re: polyspheric]
#626833
03/01/10 07:48 PM
03/01/10 07:48 PM
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Joined: Aug 2009
Posts: 2,076 Mooresburg, Tn
'72CudaRacer
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Quote:
Weight off pistons: 225 grams × 8 = 1800 grams reciprocating weight = 63.49 oz. Weight removed from crank for balance @ 50% factor: 900 grams rotating weight = 31.75 oz. Total weight off crank: 2700 grams = 95.24 oz. = 5.95 lbs. just for the pistons.
Weight off rod bearings: 4 grams × 8 = 32 grams rotating weight + 32 grams balance = -64 grams = 2.26 oz.
Rod weight loss: you added the 8 grams that you identified as a loss. In addition, we don't know how this was distributed.
So, is this a good thing? Or just useless knowledge? With this amount of weight reduction, will it make a diffence as to what the engine will "see"? I'm thinking that it can't hurt.
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Re: Rotating Assembly Weight Reduction
[Re: 65racer]
#626834
03/01/10 07:50 PM
03/01/10 07:50 PM
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Joined: Aug 2009
Posts: 2,076 Mooresburg, Tn
'72CudaRacer
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Quote:
Brian,
I shot you a PM, let me know if you got it, been having internet service problems
Dave
No mail from The Champ.
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Re: Rotating Assembly Weight Reduction
[Re: Sport440]
#626835
03/01/10 08:55 PM
03/01/10 08:55 PM
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Joined: Apr 2006
Posts: 3,675 Akron, Ohio U.S.A.
roadhazard
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Akron, Ohio U.S.A.
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Quote:
Hey Greg I see what happend with the 4.77# vs the 6.88#
Brian had both sets of numbers listed in grams 3126 - 2136 and typoed a 3 and 2 switch. You did the math for the 3126, Brian did the math for 2136. After rereading the post the 2136 gram number is the correct one. So 4.7# is the number.
6.8 - 4.7 its all in the right direction. mike
Yes Mike it's all in the right direction
Brian those mods should pick your car up a bunch and with a lighter bob weight it should be more durable also You have a Sweet looking ride. What's her best time and MPH?
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Re: Rotating Assembly Weight Reduction
[Re: roadhazard]
#626836
03/01/10 10:14 PM
03/01/10 10:14 PM
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Joined: Aug 2009
Posts: 2,076 Mooresburg, Tn
'72CudaRacer
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Brian those mods should pick your car up a bunch and with a lighter bob weight it should be more durable also You have a Sweet looking ride. What's her best time and MPH?
Thanks Greg, Most of the tracks around here are 1/8 mile, except Bristol and even they run brackets on 1/8. Mid to high 6.8x, @ 98-99 mph, 60' 1.46/1.47. Last spring we went to Z-Max for Pinks All Out, 1/4 mile at approx 600' lower altitude, I went 10.873 @ 122.29, 1.481 60', 1/8 mile on that same pass was 6.869 @ 98.77. I'll include a photo from the rear of that pass. Car weighs 3270 lbs w/ me, SS springs, 11.5 X 29.5 MT, all steel, fiberglass hood. I really don't have a clue as to what this new engine will do, I just hope it don't mess up my combination. This car has always been deadly consistant. The guys that I race with will tell you that my reaction times will be from .00x-.070, but count on the car running dead on.
Last edited by '72CudaRacer; 03/01/10 10:54 PM.
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Re: Rotating Assembly Weight Reduction
[Re: Streetwize]
#626838
03/02/10 01:20 PM
03/02/10 01:20 PM
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Joined: Jan 2003
Posts: 10,150 Frostbitefalls MN (Rocky&Bullw...
gregsdart
I Live Here
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I Live Here
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Posts: 10,150
Frostbitefalls MN (Rocky&Bullw...
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Another factor is RPM at launch/total rpm loss and recovery in each gear. The less rpm change, the less gain. A super speedway nascar racer probably won't see much, but a car with a tight converter and wide gear splits will. Other factors would be change in size of any rotating part exposed to the crankcase, which would change the drag from windage.
8.582, 160.18 mph best, 2905 lbs 549, indy 572-13, alky
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Re: Rotating Assembly Weight Reduction
[Re: gregsdart]
#626839
03/02/10 09:36 PM
03/02/10 09:36 PM
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Joined: Jan 2003
Posts: 6,591 Canton, Ohio
Sport440
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I like the combined two aspects that both Wize and Greg point out. 1. The motor underload can only rev as fast as the load its driving through will allow it. 2. The limited RPM rev range in witch the said motor will operate in with its combined vert stall and rpm shift points. Both combined would have a effect on any total net effective HP gain of any rotational weight losses. IMO, no doubt theres a performance gain, but the bigger gain IMO would be the reduced G forces on parts by thousands of pounds. mike
Last edited by Sport440; 03/03/10 12:00 AM.
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