Thread: 400/406 Builds
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Old 07-04-2020, 03:31 PM   #136
SCOTI
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Re: 400/406 Builds

Quote:
Originally Posted by kwmech View Post
May be a little too much cam for the compression, but with the 4.11 gearing you may not even notice. Definitely will be a tire burner
Quote:
Originally Posted by Captainfab View Post
I agree with a little too much cam for the static compression. Have you calculated the dynamic compression? Also the intake port of the heads is a bit too big for the rest of the combo. IMO a 180-195cc intake would be better for your power goals. I hope your tires are fairly tall with those 4.11 gears. A 650-750cfm carb would be fine.
Curious about these statements. When I do the math, it calcs out to about a 9.6:1 Static/8.4:1 Dynamic compression. The In/Ex duration @ 224° seems mild given the larger displacement of the small-block (406 vs. 355). I see many, many recommendations for around 230° for a 400+ cube motor. The head port sizing does seem off but I tend to go smaller than what the typical magazine builds suggest. When I calc'd this combo out, it estimated 400hp @ 4800rpm. TQ should be more than that as it's a mild motor combo.

Just curious of what I'm not seeing/considering.
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