Check out http//:
www.dndmotorsports.com They have some great stuff. I would also go with the 331 I herd that the 347 is good for power but not for the daily driver for reliability. Depending on the way you drive it the most I have ever herd anyone get out of a 347 is around 50-60,000 mi. Also if you are planing on a power adder go forged on the crank also hope this helps you out.