77 400 compression
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77 400 compression
i am rebuilding my 400 and i would like to get the compression up a little bit. the cam i wanna run suggests 9 to 1 but i i cant find the pistons to do it i would like some hint as to what to do
Tuned
Joined: Jun 2004
Posts: 338
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From: Northern MA
Howdy, is that the 400M? You might find some earlier model 351C high compression (closed chamber) heads and I think they're the same pattern though not positive. High compression will give you good power but it relegates you to high octane gas. I'd bet your cam will work fine with the stock compression. Badger should have some higher compression pistons for you.
Posting Guru
Joined: Mar 2009
Posts: 1,357
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From: Alston, MI
either find a 400 out of a 71 ford, lincoln, or merc because they have 9:1 compression pistons. or get cleveland heads (i don't remember what head exactly, but there is one that bumps it past 9:1 without changing pistons)
Sealed Power Z427P - Sealed Power Cast Pistons - Overview - SummitRacing.com
these pistons don't have valve reliefs, which i think are the same style as the 71 400. the compression calculator brings it up to 9.14:1 but i may have been mistaken with my numbers
Sealed Power Z427P - Sealed Power Cast Pistons - Overview - SummitRacing.com
these pistons don't have valve reliefs, which i think are the same style as the 71 400. the compression calculator brings it up to 9.14:1 but i may have been mistaken with my numbers
Posting Guru
Joined: Mar 2009
Posts: 1,357
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From: Alston, MI
you can also get the deck machined .05" so the piston gets a bit closer to the head (the 400's pistons never make it close to the head). that should bump up your CR a bit, but you'd also need to get your intake manifold machined right to fit. shave the bottom of the intake where it meets at the valley pan and get thicker intake gaskets that meet up at the heads.
Fleet Mechanic
Joined: Nov 2010
Posts: 1,501
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From: Axtell, TX
TMeyer, Inc. Precision Automotive Machining
There ya go. Tim Meyer is the man for the 335 series. I don't want to start a war here, but he is correct in calling it a 400, not 400m. 302C(australia), 351C, 351M, 400, that's the engine family. Best of luck.
Oh and welcome to FTE!
There ya go. Tim Meyer is the man for the 335 series. I don't want to start a war here, but he is correct in calling it a 400, not 400m. 302C(australia), 351C, 351M, 400, that's the engine family. Best of luck.
Oh and welcome to FTE!
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