377

SuperBuickGuy

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Joined
Jul 16, 2012
Messages
3,859
Location
Seattle, WA
I've been dancing around the edge of doing this for awhile - and I think I'm going to jump in.

I have a 400 block, 4 bolt splayed caps, 200 cfm aluminum heads and a C3 Corvette that was supposed to be a quick flip... I think I'm going to jump all in and make this car far less streetable with a motor that only works at higher rpms.

Plans:

the heads are 64 cc, 208/160 valve heads
the block is a seasoned 2 bolt main
I have billet, splayed caps
I have the comp cams spec, but presume it's large by huge solid-roller.
single plane intake, double pumper carb
bore will be stock or cleaned up stock .010
6.0 rod
3.48 steel crank
hyper pistons, though I may use forged... cr of 12.0 (and no, I don't care that I have to use race gas, e85 is available, and I'll run that if I do much of any driving)
4 speed trans
3.55 gears
 
I've been dancing around the edge of doing this for awhile - and I think I'm going to jump in.

I have a 400 block, 4 bolt splayed caps, 200 cfm aluminum heads and a C3 Corvette that was supposed to be a quick flip... I think I'm going to jump all in and make this car far less streetable with a motor that only works at higher rpms.

Plans:

the heads are 64 cc, 208/160 valve heads
the block is a seasoned 2 bolt main
I have billet, splayed caps
I have the comp cams spec, but presume it's large by huge solid-roller.
single plane intake, double pumper carb
bore will be stock or cleaned up stock .010
6.0 rod
3.48 steel crank
hyper pistons, though I may use forged... cr of 12.0 (and no, I don't care that I have to use race gas, e85 is available, and I'll run that if I do much of any driving)
4 speed trans
3.55 gears

400 Blocks are pretty frail and if you going to be using good hardware its a must to get those blocks plate honed or ring seal will be compromised.

First thing is to get the block sonic tested as I have seen many of those OEM 400 castings fail and mostly it just one cylinder making the block junk.

Here is a link to look over as far as pics of cylinder distortion and this guy went through 3 builds with 400 blocks and all were junk in the end. He would have been way ahead to go to a Dart SHP block. And he was warned LOL.

http://www.stevesnovasite.com/forums/showthread.php?t=220628
 
I've been dancing around the edge of doing this for awhile - and I think I'm going to jump in.

I have a 400 block, 4 bolt splayed caps, 200 cfm aluminum heads and a C3 Corvette that was supposed to be a quick flip... I think I'm going to jump all in and make this car far less streetable with a motor that only works at higher rpms.

Plans:

the heads are 64 cc, 208/160 valve heads
the block is a seasoned 2 bolt main
I have billet, splayed caps
I have the comp cams spec, but presume it's large by huge solid-roller.
single plane intake, double pumper carb
bore will be stock or cleaned up stock .010
6.0 rod
3.48 steel crank
hyper pistons, though I may use forged... cr of 12.0 (and no, I don't care that I have to use race gas, e85 is available, and I'll run that if I do much of any driving)
4 speed trans
3.55 gears

400 Blocks are pretty frail and if you going to be using good hardware its a must to get those blocks plate honed or ring seal will be compromised.

First thing is to get the block sonic tested as I have seen many of those OEM 400 castings fail and mostly it just one cylinder making the block junk.

Here is a link to look over as far as pics of cylinder distortion and this guy went through 3 builds with 400 blocks and all were junk in the end. He would have been way ahead to go to a Dart SHP block. And he was warned LOL.

http://www.stevesnovasite.com/forums/showthread.php?t=220628

I have the sonic tester guy on speed dial - it took 4 blocks to get a block that I could sleeve on my 455 (now 430) Buick build... the nice part about this block is it's never been bored - and if I can get away with it, it won't be this time either...
 
I've been dancing around the edge of doing this for awhile - and I think I'm going to jump in.

I have a 400 block, 4 bolt splayed caps, 200 cfm aluminum heads and a C3 Corvette that was supposed to be a quick flip... I think I'm going to jump all in and make this car far less streetable with a motor that only works at higher rpms.

Plans:

the heads are 64 cc, 208/160 valve heads
the block is a seasoned 2 bolt main
I have billet, splayed caps
I have the comp cams spec, but presume it's large by huge solid-roller.
single plane intake, double pumper carb
bore will be stock or cleaned up stock .010
6.0 rod
3.48 steel crank
hyper pistons, though I may use forged... cr of 12.0 (and no, I don't care that I have to use race gas, e85 is available, and I'll run that if I do much of any driving)
4 speed trans
3.55 gears

400 Blocks are pretty frail and if you going to be using good hardware its a must to get those blocks plate honed or ring seal will be compromised.

First thing is to get the block sonic tested as I have seen many of those OEM 400 castings fail and mostly it just one cylinder making the block junk.

Here is a link to look over as far as pics of cylinder distortion and this guy went through 3 builds with 400 blocks and all were junk in the end. He would have been way ahead to go to a Dart SHP block. And he was warned LOL.

http://www.stevesnovasite.com/forums/showthread.php?t=220628

I have the sonic tester guy on speed dial - it took 4 blocks to get a block that I could sleeve on my 455 (now 430) Buick build... the nice part about this block is it's never been bored - and if I can get away with it, it won't be this time either...

It does not mater if its bored or not as I have a stock 400 with .128 on the thrust on one cylinders and the block is junk, 400 blocks are not worth sleeving as I said they are a frail block, thin decks, thin cylinders and weak webbing.
 
the motor that was sleeved was a 455 Buick - when there is talk of a weak block, that is the poster child (the 400 is the Atlas man comparatively) - thus, it also got a cast-iron girdle and a lifter girdle as well. Value priced? no; but keeping a Buick in a Buick is valuable to me.

there is no chance I'd spend the money to sleeve the 400, even if it were strong enough... but the point was I know a sonic guy and I'm using him first. If that turns out wrong, then I simply won't do this build - my first love would be a bbc 427, the 377 would simply be a less-costly, less-intrusive alternative... until it's not, then it's not going to happen.
 
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