400 blocks

[Aaron]

I have question about 400 chevy blocks. I have been offered a 400 4 bolt main block. I have heard the 2 bolt main blocks are stronger. Why is this. Would the 4 bolt block be suitable to build a 550 hp bracket race motor. One more question would a scat cast steel crank hold up in a 550hp application like this. Any input would be appreciated.

[Mike Stark]

The 2 bolt blocks are a little stronger in the main webbing due to the lack of the two extra big holes for the extra bolts. The 4 bolt block will be fine for the motor you want to do. They can hold quite a bit of power with no problem. The crank will be fine too. Just set your clearnaces right and you'll have no trouble.