400sb from a '73
Evangelion
02-18-2004, 09:49 PM
I have a stock 400smblk with a 2barrell carb. Im wanting to know the stock specs of it, like; HP, Compression, Stroke, Bore... Im planning on dropping it in this truck I have sitting around untill I can find a suitable car that i can drop it in to. So my question would be; Where can I find stock specs on engines like that? And if anyone already knows this info, what is the stock HP, Compression ratio, Stroke, and Bore?
dxrflyboy
04-11-2004, 07:22 PM
4.125" bore, 3.75" stroke, 8.5:1 compression, probably around 175 net hp.
400 oddities:
5.565" connecting rods vs. 5.7" for all other SBC's
"siamesed" cylinder bores with "steam holes" in block & cylinder heads
2.65" main journals vs. 2.45" for all other '68-up SBC's
externally balanced crankshaft used counterweighted harmonic balancer and flywheel
Block casting #3951511 has 4-bolt mains; other 400SB castings machined with 2-bolt mains. '73 could be 3951511 or 330817
400 oddities:
5.565" connecting rods vs. 5.7" for all other SBC's
"siamesed" cylinder bores with "steam holes" in block & cylinder heads
2.65" main journals vs. 2.45" for all other '68-up SBC's
externally balanced crankshaft used counterweighted harmonic balancer and flywheel
Block casting #3951511 has 4-bolt mains; other 400SB castings machined with 2-bolt mains. '73 could be 3951511 or 330817
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