Limited Modified Rod choice?

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I have rods in flatheads that's been run for years like Mr Carlson said, I have S/A animals and small block opens, with the same rods for 3 years now, just change the bearings every 6-8 races, I guess it depends on oil and how often you change it also.
aluminum fatigues. ask a top fuel mechanic how often the aluminum rods are replaced. doesn't matter about a replaceable bearing or what oil was used.

ARC does a lot of stupid things to their rods such as leaving all the tool paths on the surface and carving their logo and information into the rod itself. these are stress risers and would make any mechanical engineer cringe. the rods would benefit from being polished and shot peened like the horseman rods were done. I do like they use the proper I beam profile and not that H beam abomination.

there are stock rods in 5hp briggs flatheads on log splitters and generators that have done a fair deal more than 3 years.
 
The old Horstman H-beams were practically indestructible. I bought this rod around 1993. I don’t think I’ll run it again, lol, but it didn’t bend or break.
 

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aluminum fatigues. ask a top fuel mechanic how often the aluminum rods are replaced. doesn't matter about a replaceable bearing or what oil was used.

ARC does a lot of stupid things to their rods such as leaving all the tool paths on the surface and carving their logo and information into the rod itself. these are stress risers and would make any mechanical engineer cringe. the rods would benefit from being polished and shot peened like the horseman rods were done. I do like they use the proper I beam profile and not that H beam abomination.

there are stock rods in 5hp briggs flatheads on log splitters and generators that have done a fair deal more than 3 years.
we not quite at top fuel HP yet, some people way over think these little engines, with spread sheets, calculations, formulas, us older guys put engines together with what we know works, in many years of racing I can count on one hand or so, how many engines we blew and it still works just fine today.
 
The old Horstman H-beams were practically indestructible. I bought this rod around 1993. I don’t think I’ll run it again, lol, but it didn’t bend or break.
Because they are over built and heavy. Carillo invented these things because they are easier to machine.
All the engineers at Honda, Chevy, Ford Toyota Yamaha KTM parilla triumph Norton Kawasaki Suzuki Ferrari Porsche briggs Oliver CZ husqvarna BMW Mercedes PCR etc etc all agree the I beam rod is the correct shape
 
he said " it provides some cushion for the explosion that happens 10,000 X per minute in a limited." My math tells me that's 20,000 rpm
You can't be serious in your critique of my writing about the number of revs and firing events in a limited. I guess, like you, I could have enlightened everyone with my vast knowledge and experience of the overlap firing of a 4 stroke Briggs. You are absolutely correct. The number of times it fires is twice that of the rpm read on the tach. BUT, the number of times the plug fires was not my point at all, it was the excessive rpm we turn these engines and subsequent load the rod bearing needs to endure.
And for what it's worth, if I could turn a limited 20,000 rpm and it still live, you know darned well we'd all be doing it!
 
You can't be serious in your critique of my writing about the number of revs and firing events in a limited. I guess, like you, I could have enlightened everyone with my vast knowledge and experience of the overlap firing of a 4 stroke Briggs. You are absolutely correct. The number of times it fires is twice that of the rpm read on the tach. BUT, the number of times the plug fires was not my point at all, it was the excessive rpm we turn these engines and subsequent load the rod bearing needs to endure.
And for what it's worth, if I could turn a limited 20,000 rpm and it still live, you know darned well we'd all be doing it!
I knew exactly what you meant. I was just messing with you.
 
Actually a Briggs fires every revolution.
mine fires 31 degrees before tdc on overlap. My in valve opens at 60 degrees btdc. On over lap. Is it waisting any air and fuel coming in? How much cfm is there between 60 degrees btdc @ .006 lift? Versus 16 degrees btdc @ .050 lift?
 
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