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Discussion Starter #1
Hello, Would a shaved crankshaft do any good for a GA16?? or the improvement is not worth the effort??

I had mine shaved but I didnt notice any gain
Thx.
 

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GA16DE
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606 Posts
Hi
By shaving you refer to retire part of the counterweights metal?
Any pics?
 

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Discussion Starter #3
velardejose said:
Hi
By shaving you refer to retire part of the counterweights metal?
Any pics?
You are right, shaving = removing part of the counterweights
 

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Erin Go Bragh!
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wes said:
It will decrease rotating mass which is the same as lightening the flywheel.
Does that help with direct hp, or is it unnoticeable?
 

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wes said:
Totally noticable in acceleration and decelration, also less stress on internal reciprocating components.
I thought the counterweights were designed with the weight of the stock rods and pistons in mind. Does lightening one and not the other unbalance things and induce vibration?
 

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Wise Cracker
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94econobox said:
I thought the counterweights were designed with the weight of the stock rods and pistons in mind. Does lightening one and not the other unbalance things and induce vibration?
This is precisely why this needs to be done by a shop that can lighten and balance the crankshaft. It is also best to use rods that have been balanced end to end within 1 gram. Just makes the assembly that much better/more reliable!
 

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So with a lightened and balanced crank and lightweight/balanced pistons and rods should allow for reliable revving to 6300 rpm time after time, eh? Is there a limit to this, i.e. if this were combined with a lightweight flywheel, would the reciprocating mass be so low, it'd be hard to drive around town (engine slowing quickly between shifts)?
 

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Wise Cracker
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94econobox said:
So with a lightened and balanced crank and lightweight/balanced pistons and rods should allow for reliable revving to 6300 rpm time after time, eh? Is there a limit to this, i.e. if this were combined with a lightweight flywheel, would the reciprocating mass be so low, it'd be hard to drive around town (engine slowing quickly between shifts)?
This is not something most people do on a street car. Not that it can't be done but it is expensive and is not a bang for the buck mod. It will affect drivability to a certain degree just like a lightweight flywheel does. So tooling around town will likely not be as comfortable as it as with the stock motor. But in the world of high performance it is worthile. And revving to 6300 RPM's is a non issue on our cars, assuming you meant 7300 then yes!
 

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Soggy GloryHoler
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even having just a lightened flywheel is too much to get used to for alot of drivers, so having a complete lightened drivetrain is not going to be easy for the street, its your money so yeah it is very expensive and not worth it for most..........would be very twitchy and jerky for the average person........
 

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Discussion Starter #13 (Edited)
To tell you the truth it wasnt's that complicated for street driving, in fact it was almost the same feeling as a lightweight flywheel, nothing more nothing less.

The crank was shaved and balanced, but I'm not sure if the rods were, so maybe that would be a reason for the metals to fail?? I know it was also mentioned that the 8400 rpms were not safe but maybe the "unbalanced" rods helped??? (btw wes, I'm the slow rpm lerner :thumbdwn:).

When opening the motor to replace the damaged parts, they told me that the crank had a fissure in the same point the metals broke (3rd cylinder) so I will have to replace the crank, I'm considering a stock crank cause as Wes mentioned before, It was not a bang for the buck, what would you recommend?




Regards
 
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