Are you talking about Redline beyond 10 grand--safely under boost??? or are u talking about N/A becuase i doupt that ur going to take a boosted engine up to 10,000 RPM and it be safe in any car... built or not... i mean i know its been done but its going to cost a lot of money and i hope u have a lot of money if u plan on doing that to a even semi built B18 or B18C5