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Discussion Starter #1
Talking to my machinist today and I asked about busing the Bowtie 6 inch rods I have in the 377. His comment is they were too heavy and to consider another lighter rod if I'm wanting to rev quickly. This rod is 4340 degassed, shotpeened, profile beam, using 7/16 ARP cap screws and locating sleeves. The rods came out of the 355 this fall and I was pleased with how that engine revved. I guess having spun rod bearings in two seperate 3.48 stroke motors years ago using Chevys pinked rods I tend to place a beefier rod big end above a quick revving motor. I'm also running the larger flywheel and thick balancer so it isn't going to rev quick anyway IMO.

I can't find the weight anywhere listed for the 6.0 rod, the 5.7 is 739 grams and the profiled 5.7 is 690 grams. Mine are profiled 6.0, I'll weigh them this week. The 5.7 profiled at 690 has 529 of it's weight on the big end. I've read the I beam is stronger in compression, where the H beam is stronger in torsional loads. This is going to be somewhere around 11.5 static comp motor that will go to 6500-7000 rpm occasionally. Not real high rpm like the shorter stroke sbc. So I'm not certain it calls for an H beam, which from the listings I'm looking at aren't real light either.

Looking at Lunati Pros and Crower Sportsman I beam rods they are also heavy if not heaiver than the Bowtie. So is the heavy rod really an issue especially since I'll only be using a 3.48 stroke and not going to wind it really high?

What are everyones thought regarding an oil hole in the small end, single hole from the top down, two holes from the bottom up?

Just when you think you've got a plan, another thing to consider comes up.

Thanks guys.
 

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Discussion Starter #2
Guess what I'm asking in a nutshell is In know it's a balancing act between durability (heavy) and light weight (quick reving, less stress on crankshaft). But in a car that'll be 95% street driven and then see only limited use, the heavy Bowtie rod should be fine because I should be placing my emphasis on durability anyway? GM claims 10,000,000 cycles on the Bowtie rod without any failures so I'm leaning towards keeping them.
 

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I would keep them. Your right with that heavy flywheel/balancer combo she's not going to spin up all that fast anyway. And with this being a street combo anyway I would worry more about the durability that the power as well.
 

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You should be able to use a really light piston to help offset some of that weight anyway, so since you already have them I would use them.
 
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