I'm no expert but I'll tell you a few things to try...
Easiest and cheapest is to work in your timing curve. I like to try 20 initial with 38 total in by 3000 rpm. Work up to that until you hear detonation. That will probably perk you right up.
I would recommend a Performer RPM intake instead of the regular performer.
You might want a bigger cam. I had picked that cam for my pickup truck, but in a cobra you can use more.
Here is a desktop dyno plot of my isky cam vs the crane in my 390 build.
Chuck
