diff connecting rod lengths make ?
07-03-2010, 07:03 PM
#1
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diff connecting rod lengths make ? want to build a forged bottom end in 94 Z. 5.7 or 6.0 rod length ? what difference does the length make in performance ? thanks for your help 
t
t 
07-03-2010, 07:09 PM
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6 has been the rule of thumb for 350, 383, and 400 SBC combos for a long long time. Almost everyone who builds rods offers one because its very common choice for a little extra performance with no real sacrafice. Little less side loading on the piston, overall better rod length/stroke ratio versus stock, and I think they even help the piston dwell time at TDC.
You have to buy rods anyway so get the 6" rods. No real cost difference and they're worth a horsepower or 10, or 15.
You have to buy rods anyway so get the 6" rods. No real cost difference and they're worth a horsepower or 10, or 15.
07-03-2010, 08:42 PM
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I was always under the impression that there really is not any "performance" gain. The only thing rod length really effects is the side loading ant the valve timing events, which in effects the dynamic compression ratio. For everything I have ever read, there has been a big debate on whether or not any performance value could really be had on a longer rod or not. Not just this site, but on other engine building sites as well.
But then again I may be way off....
But then again I may be way off....
07-04-2010, 12:37 AM
#5
depends on what you're trying to do with the motor. N/A get the ring pack up high on the piston, and run the shortest CH you can. Rod length is whatever you're left with. Honestly with a low rpm steel rod motor I don't think there's any advantage running a long rod, and definitely no advantage in the pocket book with a custom piston/rod length.
