When comparing two different connecting rods in the same length, say a 6.125 SBC rod, and one is 690g and the other is 610g. Is it the overall weight you are comparing or is it more important to pay attention to the small and big end weights. I know it will make a difference when balancing. But what about horsepower or the ability for the motor to spin faster. Just curious.
Connecting rod weight
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you'd have to see the rod design but typically you want the weight on the big end and the beam. But that really depends on the rod design etc adnuaseum,.
Bobweight was 1800g(Lunati) rods compared to 1890g(Howards)rods.
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Is this a N/A motor? That 1800-1900g would be mid to heavy so I don't think there would be a difference in the end.(Performance wise)
1500-1650g light, 1700-1850 mid, 1900+ heavy IMO for most without getting into max effort N/A stuff.... IMO
Most of the time Drag race engines need strength. Stregth is what is sacrificed.
T-flow
1500-1650g light, 1700-1850 mid, 1900+ heavy IMO for most without getting into max effort N/A stuff.... IMO
Most of the time Drag race engines need strength. Stregth is what is sacrificed.
T-flow
Max RPM is anywhere from 7800-8200
Piston, pin, rings, and locks were 618g
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What are the two rods? what bolts in them?
IMO, without knowing the combo. The weight difference will have very little to do with ET, at that weight. But the lighter Bobweight will help exceleration.
Not sure what rods, but the Howards Billet rods 674g @6.125", Lunati Pro mod rod 672g @6.125"
My book may be wrong, but thats what I come up with...
I like the Howards rod! ARP2000 standard
T-flow
IMO, without knowing the combo. The weight difference will have very little to do with ET, at that weight. But the lighter Bobweight will help exceleration.
Not sure what rods, but the Howards Billet rods 674g @6.125", Lunati Pro mod rod 672g @6.125"
My book may be wrong, but thats what I come up with...
I like the Howards rod! ARP2000 standard
T-flow
Howards 481g/209g weights Heavier then advertised
Lunati 453g/170g weights Proseries
Both have the same rods bolts, 95g difference in bobweight 1800 to 1895. The crankshaft box says balanced to 1750g.
I'm sorry N/A single carb Ls 408. Solid roller, 15.1 compression, 365 cfm heads. The crankshaft company website said it was factory balanced for a 1820g bobweight, but the folks I ordered through only sale them at 1750g. I should of asked my fault. Looks like I'm going have to add metal to the crank either way. For folks reading this thread, weight your rods, pistons, pins, etc. and know your bobweight and order your crankshaft accordingly. Big learning curve for me.
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Ouch.....Good luck!
I would think that the Light weight Billet ones would hold up. L19 bolts and that RPM 8200 shouldn't be a problem. I thought this was a 9000+rpm deal or large ci. sheet metal with twin's on it... Maybe an adjustment in piston lightening or pin could help aswell? Just a thought. Maybe some of the Big dawgs will chime in and have some input on this Ls build.
Bret Bauer might have some imput aswell, he has built some Ls motors.
T-flow
I would think that the Light weight Billet ones would hold up. L19 bolts and that RPM 8200 shouldn't be a problem. I thought this was a 9000+rpm deal or large ci. sheet metal with twin's on it... Maybe an adjustment in piston lightening or pin could help aswell? Just a thought. Maybe some of the Big dawgs will chime in and have some input on this Ls build.
Bret Bauer might have some imput aswell, he has built some Ls motors.
T-flow
I appreciate the response. Thought I would ask. No one in my area is into these motors yet, especially N/A. So I picked everything out on this motor myself. My machinest is a long for the ride. Plus I'm learning everything about machine work, clearences, and picking out the right parts. It's been a big learning curve for me to say the least.
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