The car is a mostly stock Evo 7 & was perfectly fine.
I performed the following:
-Removed the head & had it ported & reinstalled again.
-Changed the timing belt with a new oem belt
-Changed the balance shaft belt with a new oem belt

Now, the engine has moderate vibrations after performing the above steps, whether the gear is engaged or in neutral!

Any suggestions?

 

balance shafts are probably out of phase..

 

Can you elobrate further? And how to remedy it?

 

A lot of people forget to rotate the oil pump gear 180....only if it needs it. When you turn the gear and release it....the arrow should fall back in place with the notch on the case.

 

Yes, sure, I've done that.

 

Could even be something as trivial as a boost leak causing an erratic idle. You didn't give us very much information.

 

Does it vibrate at idle? Or when revving the engine up

 

Timing out by a tooth?

 

The timin belt could be to tight. That has happened to me. Had to re due the tensioner

 

Good bet the balance shafts got timed wrong.

 

Upon revving, it's maximized at around 4000 whether in gear or neutral
No boost leaks & I have checked the timing belt & it seems fine, not too tight!
I'm positive that balance shafts setup is fine but I currently have no other option but to recheck them again.

 

Like I said before, your belt is probably to tight if you know for a fact the oil pump gear is correct