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Discussion Starter #1
Just pulled apart a motor I'm going thru and found a steel cank with Eagle 6.385 H beams. Anybody use these long rods on a BBC for a pump gas jet boat? I remember hearing something about the rod ratio being better and the piston having more dwell time. Anybody have any input? Not sure if I should send these down the road and get a std set or what...
 

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mo balls than $cents$
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not sure about the facts on the rods, but i'm runnin a set with l19's. goin to water test tommorrow :)devil it ain't a pump gas deal though, but it is a lake boat. sure cleared the standard deck block good without having to break out the die grinder.
 

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E-7 Sheepdog (ret)
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Just pulled apart a motor I'm going thru and found a steel cank with Eagle 6.385 H beams. Anybody use these long rods on a BBC for a pump gas jet boat? I remember hearing something about the rod ratio being better and the piston having more dwell time. Anybody have any input? Not sure if I should send these down the road and get a std set or what...
Lake-boat/river-boat or race machine?

IMO the only time to worry about rod length advantages/disadvantages is when trying to find every single 1/10th HP in a racing class.

Otherwise, not enough difference to bother with. Run 'em.
 

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jetboataholic
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When I get the money saved up I'm going to stuff some 6.535" rods in my Chevy 427T with a stock 454 crank and the 427 pistons. Been told this makes it a stroker motor, and the parts fit flawlessly. I've got the crankshaft (got it for free, just needs a little machine work) now I just need the rods and I'll be set with a bitchin' stroker motor for my rig. Found some forged 4340 H-beam Eagles for about $460, brand new.
 

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Some guy
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When I get the money saved up I'm going to stuff some 6.535" rods in my Chevy 427T with a stock 454 crank and the 427 pistons. Been told this makes it a stroker motor, and the parts fit flawlessly. I've got the crankshaft (got it for free, just needs a little machine work) now I just need the rods and I'll be set with a bitchin' stroker motor for my rig. Found some forged 4340 H-beam Eagles for about $460, brand new.
Better rethink that a bit. The .400" longer than stock rods would work with 427 crank and 427 pistons in tall deck truck block,, or also with 454 crank and 454 pistons. The combination you mentioned would stick the piston out of the block .100" or so depending on how much the block has been decked.
 

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jetboataholic
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Better rethink that a bit. The .400" longer than stock rods would work with 427 crank and 427 pistons in tall deck truck block,, or also with 454 crank and 454 pistons. The combination you mentioned would stick the piston out of the block .100" or so depending on how much the block has been decked.

Thanks for the information. So I should use the 427 crank to make this motor a stoker? Would they still stick out that far even if the block hasn't been decked?
 

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Some guy
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Thanks for the information. So I should use the 427 crank to make this motor a stoker? Would they still stick out that far even if the block hasn't been decked?
I sent a PM to explain. The 427 crank with the 427 piston is still a 427, no matter how long of a connecting rod you use. "Stroker" is determined by the crankshaft, but the pistons and rods need to be the correct length to all work together for a given combination.
 

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E-7 Sheepdog (ret)
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Better rethink that a bit. The .400" longer than stock rods would work with 427 crank and 427 pistons in tall deck truck block,, or also with 454 crank and 454 pistons. The combination you mentioned would stick the piston out of the block .100" or so depending on how much the block has been decked.
Where's hotbo when you ned him to explain the positives of this condition? :D:D
 

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Discussion Starter #12
Looks like the oil ring is suspended over the pin holes for about a half inch or so. Also, makes for a real short piston, maybe some weight savings? I'm planning on a pump gas (10.5:1) or so aluminum head roller cam motor for a g wing, maybe a bottle down the road for river use. I've just never messed with this combo. So if these rods are 250 long, does that mean the same pistons would work with a 1/4 stroked crank with std rods in a 9.8 deck block? I think I would rather have the cubes and go with a stroker crank.
 

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E-7 Sheepdog (ret)
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