Theres deffinitely something wrong mate. You've made good power but torque is down in my eyes.
There is a massive debate on the timing issue, but as a lot of people have stated, the 4E and 5E is 2 complete different engines, the 5E just has a turbo slapped on it. I would have it on the 5E marks.
I also agree with the race inlet, it has a larger volume to fill, but also have you had any headwork? Whats that like? Oversized ports will increase lag dramatically!
Have you done a compression/leak down test?
The large 3" pipework is a bit overkill, I wouldn't go any bigger than 2.75 and even then I would say thats pushing it.
As Animal said, you have such a short power band, if your not making full boost till 5k and the limiter is at 7200, there is something wrong there.
Can you get a pic of the ignition table up?
I would be looking at the EGT's, see if your having too little ignition advance or not enough.
4E timing marks, race inlet, 3" pipework, large cylinder ports, poor ignition advance will all lead to lag. With all this re-worked you could be looking at a steep reduction in lag.