273 Build

Sounds like you're as excited as me. LOL You have a great combo going there.
I was seriously thinking about a bigger cam for mine but I was impressed at the Isky E4's power and torque for a cam that's pretty close to the stock cam. Schneider has a good looking flat tappet cam #14202 (264/480/110) that would
be my second choice. http://www.flatlanderracing.com/ (scroll down to flat tappet cams). That might be something for you to try. Mike
Schneider is in the know! He ground me a decent solid 142 F 284/284 .513 I believe. Great throttle response with 308 heads.