Ok I know some folks are going to shake their heads...

Before spend $$$ you may want to look at this thread..

http://inliners.org/ubbthreads/ubbthreads.php?ubb=showflat&Number=48429&Main=6462#Post48429

It'll run rings around even a hot 250 and get 25+mpg with bone stock reliability.. just not for everyone.

51 GMC 4.2 turbo
Can't solved today's problems using the same technology/thinking that created them