[blykins]

You still didn't answer my question. What are the pluses of a flat tappet cam?

Here's how I would handle your scenario:

I would sonic test the block, present the results to the customer, and if in my opinion I thought it would cause problems by boring it to the customer's spec, then I would tell the customer that. If they still insisted, then they can take it to another builder.

You know why? Because I don't trust anyone's words.....even if they "say" they'll assume all risk. Who's to say that the customer wouldn't turn tail and then blab all over the internet that his engine builder screwed up his $3k side oiler block?

Again, it's not worth it. I don't need the money that bad.