will it hold up good as a 408?

 

sure

 

sure, why not. just dont exceed the limits of the block and you'll be ok.

 

what would be the limits on it

 

pwoplw say the 351w block can hold about 700 MAX at the flywheel. so i would say dont over do it. In theory boring it out would make the cyl. walls thinner so i would say the overall strength and durability will be down. So don't exceed 500-550 rwhp.