Ported E-7s will work fine if done right. You will need valve springs to handle the extra lift of an aftermarket cam. The alphabet cams have been around for a while, but they do work. I have an e-cam in my motor with my current set-up. I have FRPP GT40X305 heads, BBK shorty headers, off road x-pipe, 24# injectors, 70mm TB, 76mm C&L MAF, 1.6 scorpian roller rockers, typhoon intake, 190lph fuel pump, and 3.55 gears. This set-up dynos out at 290 rwhp and 317 rwtq. With drag radials my car will run 7.93 @ 86 mph in the 1/8th mile.

Other cam makers I'm sure are doing better than the letter cams. But unless you do the whole top-end of the motor, then a cam upgrade is not going to do you much good. Hot rod magazine (I can't recall which issue) did a junk yard build -up of a 5.0 motor and was making like 372 hp at the crankshaft with the stock HO roller cam. The camshaft was the last thing they changed and power only increased 16hp. They used a Comp XE270HR camshaft. While typing this my son just brought methe issue of the magazine and it's called Hot Rod Do-It-Yourself Series ENGINES published fall 2006.

Hope this helps.