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440 balancing #2964767
09/16/21 06:21 PM
09/16/21 06:21 PM
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WI
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68hemiss Offline OP
mopar
68hemiss  Offline OP
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Are there some machinists out there who can help with a 440 balancing question? I am re-building a blown 440 for a friend. It was originally a std bore, stock .010"/.010" forged crank with TRW pistons and stock rods. We changed to Eagle H-beam rods and SRP (JE) pistons. I am working with a machine shop who builds racing engines - this is the first time I have had them do any work for me and he is telling me that the crank is modified and he can't balance it. He says that "the counterweights have been machined and that someone has cut grooves in the counterweights". He told me that "he has to take 200 grams out of the crank which is almost impossible". Look at any 440 crank and the rear counterweights are machined on outside diameter and the grooves that he is talking about are also in all 440 cranks. How do I respond to him? Thanks

Re: 440 balancing [Re: 68hemiss] #2964771
09/16/21 06:46 PM
09/16/21 06:46 PM
Joined: Oct 2005
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Ontario, Canada
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Stanton Offline
Don't question me!
Stanton  Offline
Don't question me!
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Find another shop !!

Also, 200 grams is close to a 1/2 pound ... did he leave a piston and rod out ?!?!




Last edited by Stanton; 09/16/21 06:49 PM.
Re: 440 balancing [Re: Stanton] #2964772
09/16/21 06:50 PM
09/16/21 06:50 PM
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Super Spudsville
Mr PotatoHead Offline
Half Baked
Mr PotatoHead  Offline
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Super Spudsville
X2 on another shop.

I like light stuff and use a spec 2050 gram crank and we go to 1700 gram bobweights with zero issues.




Originally Posted by Stanton
Find another shop !!

Also, 200 grams is close to a 1/2 pound ... did he leave a piston and rod out ?!?!





STOP POTATO HATE!
Re: 440 balancing [Re: 68hemiss] #2964821
09/16/21 09:00 PM
09/16/21 09:00 PM
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Oregon
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AndyF Offline
I Win
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Oregon
If the shop has a big lathe he can take 200 grams off the crank bobweight by cutting the counterweights down. If he doesn't have a big lathe then you might be out of luck.

Re: 440 balancing [Re: 68hemiss] #2964837
09/16/21 09:39 PM
09/16/21 09:39 PM
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Missouri
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jwb123 Offline
super stock
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Missouri
I am not a machinist, but I have built several BBM with the kind of short block you describe, balancing was never a problem. I would select a different shop.

Re: 440 balancing [Re: jwb123] #2964898
09/17/21 07:27 AM
09/17/21 07:27 AM
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Apollo, PA.
B1MAXX Offline
top fuel
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Apollo, PA.
Sounds like an excuse to me, I mean come on, you could use a grinder, if it came to it. sawzall 200gr doesn't surprise me.

Re: 440 balancing [Re: 68hemiss] #2964909
09/17/21 08:31 AM
09/17/21 08:31 AM
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NC
440Jim Offline
I Live Here
440Jim  Offline
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NC
Originally Posted by 68hemiss
He told me that "he has to take 200 grams out of the crank which is almost impossible".

A factory 440 has a bobweight over 2700 grams (depending on year etc.)
Just reducing all the counterweights from 7.50" dia to 7.44" dia would remove about 200 grams.
Alternatively, drilling a 1" dia hole 0.9-inch deep (plus the drill tip) in both the front and rear counterweight will remove about 200 grams.

Not a problem at all. I have seen more holes before.

crank throw rear.jpgBalancing_Drill_Point_Chart.jpg
Re: 440 balancing [Re: 440Jim] #2964929
09/17/21 09:56 AM
09/17/21 09:56 AM
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fredericksburg,va
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cudaman1969 Offline
master
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fredericksburg,va
He said the crank “was modified” well he certainaly don’t wanna see my ‘balanced’ Hemi crank

Re: 440 balancing [Re: 68hemiss] #2965064
09/17/21 06:04 PM
09/17/21 06:04 PM
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Posts: 489
IL
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EchoSixMike Offline
mopar
EchoSixMike  Offline
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Joined: Jul 2009
Posts: 489
IL
200gms remove isn't a problem, when it's 200+ gms "add" you start getting angry at the customer and take it out with the billing pen. This guy isn't familiar with the job or doesn't want to do it. Take it elsewhere. S/F....Ken M

Re: 440 balancing [Re: cudaman1969] #2965067
09/17/21 06:42 PM
09/17/21 06:42 PM
Joined: Oct 2003
Posts: 664
WI
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68hemiss Offline OP
mopar
68hemiss  Offline OP
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WI
Thanks, I would think that this would be a non-issue but the local machine shop that I have used for years closed a few years ago - never had a problem with them - they even used to build USAC Hemis back in the 60-70s. I have been trying different shops, but I guess you don't know how good you have it until you don't have it anymore.

Re: 440 balancing [Re: 68hemiss] #2965115
09/17/21 09:36 PM
09/17/21 09:36 PM
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Posts: 43,007
Bend,OR USA
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Cab_Burge Offline
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Bend,OR USA
"Machine shops" are a lot like other professions, you have to look hard to find the best ones scope up


Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)






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