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post #1 of (permalink) Old 02-28-2006, 08:27 PM Thread Starter
 
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400ci? Opinions?

The search continues... I've found a couple of contenders, but none of them are EXACTLY what I'm looking for... it changes daily anyway, so it may be a while.

Anyway, I found a '78 that is in pretty good shape that has a 400ci in it. What do you guys think of this motor? I am really looking for a 350 because parts are plentiful and cheap.... but I don't know anything about the 400, so I can't comment.

What do you guys think?
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post #2 of (permalink) Old 02-28-2006, 09:07 PM
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Re: 400ci? Opinions?

never owned one. but the grape vine says they had cylinder wall problems. mainly overheating. but who knows if it is true.

if the truck is in good shape, i'm sure you could swap in a 350 bottom end. even rebuilt they are not to bad, around $1500. you could use the crank to make a stroker 350, a 383. 400 crank into a 350.
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post #3 of (permalink) Old 03-01-2006, 12:33 AM
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Re: 400ci? Opinions?

We've got two 400s, one with ~75k miles on it and runs like a champ (mine). The other has unknown miles on it and needs a rebuild. The heads need refreshing and it looses a little compression past the rings. Neither get anywhere near overheating in the summer while running A/C. I've got a heavy duty fan clutch on mine and keep my cooling system up to snuff, it rarely gets above the 155 degree mark. I too have heard the too thin cylinder wall story too, but have never seen problems first hand.
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post #4 of (permalink) Old 03-01-2006, 07:46 PM
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Re: 400ci? Opinions?

The 400 will take many parts the 350 will as well. the aftermarket has them covered very well, so dont be shy towards one!
post #5 of (permalink) Old 03-02-2006, 09:26 PM
 
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Re: 400ci? Opinions?

my 400 has never left me stranded. If you're looking for a motor, the 400 would be my first choice. They may not be as popular as the 350, but in my experiences, the 400 runs and performs better than the 350 on my newer truck.
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post #6 of (permalink) Old 03-06-2006, 09:26 AM
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Re: 400ci? Opinions?

400 Is definitely a stronger performer than a 350 in these heavy vehicles. I've owned many of each. NO shortage of parts for 400's.
overheating? Heck,these days you can buy a new HD 3 or 4 core radiator on-line for $150.
The cylinder walls are siamesed together with no water jacket between that's why they had a rep for overheating. A Good(meaning effective) cooling system is all thats needed. Don't try to rev it like a 350 either. Don't need to. DAVE
post #7 of (permalink) Old 03-06-2006, 12:59 PM
 
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Re: 400ci? Opinions?

My 79 K5 had the 400 in it.............it was a freaking monster!!!!.......I loved it.........power to spare and very reliable.

No worries about the 400........
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post #8 of (permalink) Old 04-30-2006, 03:49 PM
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Re: 400ci? Opinions?

The block is actually stronger because of the siamesed cylinders. And it has a fatter crank (2.65" mains), shorter rods (5.565") and what else?... yeah, steamholes. Don't hesitate if it's a 2-bolt block. With the thicker mains a 2-bolt with a little help from Arp makes for a better bottom end. But a 4-bolt won't explode in your face either, so don't sell it short just because of that.

And this must be my first post in 3-4 years?! I wonder if the OG's still around?

/Andreas
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post #9 of (permalink) Old 04-30-2006, 10:27 PM
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Re: 400ci? Opinions?

There is something about the head gasket too. Steam holes. I can't remember if it has them or does not have them. I think the issue was if you did not get a 400 head gasket you ended up blocking off some water jacket passage or something.
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post #10 of (permalink) Old 05-01-2006, 03:50 AM
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Re: 400ci? Opinions?

Yup, gotta have a 400 head gasket.

Oh, one more thing - It's externally balanced.
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