What is the highest RPM for SBC 400

Old 10-15-2007, 06:47 PM
  #1  
Blue68Camaro
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Default What is the highest RPM for SBC 400

I am trying to decide what gear ratio to go with but i dont want to be at max rpm at half track. What is the max rpm that i should think about going so as not to do any damage to the engine?
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Old 10-15-2007, 07:04 PM
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SST4530
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Depends on how the engine is built and what components you used. Give some specifics.
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Old 10-15-2007, 07:27 PM
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woodsman
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How tall a tire do you have on the back. 26" / 28"
1/8th or 1/4 mile track
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Old 10-15-2007, 08:52 PM
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SST4530
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Have you had it dynoed to see what RPM max HP and torgue ocurr? Otherwise it will just be an educated or maybe an undeucated guess. :lol: :lol: :lol: :wink:
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Old 10-16-2007, 05:26 AM
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badrad
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Like blittle said, depends on how you build it. I had one in high school with stock 2 bolt bottom. Turned it to 6000 all the time with no problems. Now that I'm older and hopefully wiser I would use splayed caps on a 2-bolt block with the lightest rotating assembly I could afford. 400s are somewhat underrated, build it right and it will throw down solid big block numbers.
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Old 10-16-2007, 09:33 AM
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Building 2 400s right now, setting for 8K rpm max. But one of them I'm using a 3.625 stroke so it'll prolly still be pulling hard at 8K. Other than stroke, building them the same. Using 208 int, having ported now with a super victor.
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Old 10-16-2007, 03:48 PM
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rabiddawg
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the biggest problem with 400s is the weak webbing in the block.
I had my mains splayed and installed a crank girdle.
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Old 10-16-2007, 04:05 PM
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Short stock 5.585 rod length is bad if you intend to turn any significant RPM over 6500. Puts to much side load on the cylinder walls. Longer rod is better.
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Old 10-16-2007, 05:21 PM
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I'll be running 6"er rods, will help with detonation. Mine are 2 bold main conversions (4 bolt billet splayed caps)
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