400 sbc build

[CFH87]

Was wondering what it would take to make around 550 hp, and be able to take up to a 300 shot of juice. I've got a virgin 509 small block was thinking maybe a 434 or 406. Looking to run afr or any comparable heads and diamond pistons... Let me know what you think and what it would take thanks.

 

[SSedan64]

I'd start with an Aftermarket Block.

 

[bowtie81]

I was thinking doing the same thing as you. By the time you figure all the machining to accept a 4" stroke, which you could cut into the water jacket and possible thin wall thickness. Like already stated you'd be further off going with an aftermarket block.

 

[prairiehotrodder]

I agree about using an aftermarket block. If you must use the stock block i would not go bigger than 3.875 stroke and not bore more than .020 . I've cracked 400 cylinder walls on a .030 over 377 making 500 hp. The Dart SHP block would probably work well for what you are doing.
brian

 

[Doober]

AFR 195s, 10:1 and a cam around 235º-240º @ .050"... roller would be better. It'd be a little soft on the low end but midrange up should be a screamer.

 

[CNC BLOCKS]

I'd start with an Aftermarket Block.

X2 400 blocks at 550 horse are a crap shoot to say the least.

I have seen guys spend a ton of money on a 400 block and when bolting the torque plate on have them crack from the head bolt hole out to the cylinder making the block junk.

Dart SHP and SHP Pro block would be a good choice.

 

[CFH87]

What about a 406? Already have whats thought to be a "good" block its the 509 casting...

 

[CNC BLOCKS]

What about a 406? Already have whats thought to be a "good" block its the 509 casting...

Have it sonic tested an tell us how good t is ??