SBC Connecting Rod Length
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SBC Connecting Rod Length
I was told that I should use a 6 inches connecting rod in my Chevy 350 instead of the stock length of 5.7 inches. What are the advantages/disadvantages of using a 6 inch? Thanks in advance for the info...
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Can you share some of your testing data to prove this??BGriff wrote:Longer rod, longer dwell at TDC, better for high RPM HP.
Short rod, better for low end torque, more side loading at piston skirt.
Like how much tq increase did you see in A-B-A testing with the shorter rod??
Please list all the info of each combo and the actual TQ increase numbers.
Keith
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We see a big differance on the 2 bararrel circle track engines going from a 5.7 to 6.250 rods and from what I have seen they male peak power about the same RPM but the 6.250 rod will carry alot longer then the short rod engines.
The cam will be different for a longer rod engines as well.
The cam will be different for a longer rod engines as well.
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CNC BLOCKS wrote:We see a big differance on the 2 bararrel circle track engines going from a 5.7 to 6.250 rods and from what I have seen they male peak power about the same RPM but the 6.250 rod will carry alot longer then the short rod engines.
The cam will be different for a longer rod engines as well.
Seen the same here..
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Carl or 3V, can you give some actual numbers??? When you say carry it longer I assume you mean the peak HP father up the RPM range. How much farther???
Is this something that is only found with the 2bbl engines???
Keith
Is this something that is only found with the 2bbl engines???
Keith
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What I have seen with the longer rod is that the engine does not nose over as bad above the HP peak-- say the peak is at 7000, with a longer rod , it can carry the better power way uo to 8000. On the other hand, with a shorter rod, even when the peak is at 7000, by 8000, the power will drop off 30 to 40 HP-- The differance might be 25 more HP with the loger rod at 8000
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