What do you think about 400 stroked too 512 ? Walls won't be to thin ?
Maybe better 440 stroked to 494cui ?

This is becoming a popular combo. Rods and pistons are a little on the short side but it works OK.

but wchich one would be better ?

512

Before you spend money on the block check the thickness of the cylinder walls, it isn't the stroker kit that makes the walls too thin, it's the block casting quality.

Ultrasonic thickness testers are coming down inprice now that they are being made in C#$%a.

So measure the cylinder wall thickness before you pick a block. Either one of what you mentioned will be fine.

R.

What were you plannig for heads? 512 will want to breath. That's why I built a 451/ Eddy head, the cost of heads would have doubled the build cost to go much bigger. IMHO silly to build a large displacment engine and not put some worth while heads on it. Victors/Indys both with work done.

Let's hear the rest of the planned combo

BS. Build the biggest shortblock you can afford, then put heads on it as you can. This is advice from Chuck Senatore, one of the best bigblock guys around. OF COURSE your big engine will rev higher with power with better heads, but it is pure bunk to say it won't run at all with a smaller head.

What will happen is that the engine will have mondo torque and power up to the point where it maxes out the heads and then power above that rpm point will stay the same, torque going down in proportion to rpm. What it will feel like is unbelievable power up to a point and then no more. When you put on a better head it will make power farther up in the rpm range, too.

A stock Edelbrock head will flow about 270 cfm. That is enough for about 560 hp. If a 451 makes 560 hp at 6500 rpm the 512 will make the same power at 5725 rpm.

R.