rev problems

[xsaigen]

Hi I have an 88 csx-t and I changed the head gasket and put a new turbo on because antifreeze ran through my turbo and messed it up but when I drive it or just have it sitting in my garage. When I try to rev the engine to 6000 it stops at 2000 and just keeps hitting 2000 but if I slowly rev the engine to 6000 it goes all the way up but when i let it go under 2000 it stays under 2000 and also it idles just fine if that helps any. plz help

[NAJ]

Is the check engine light on or are there any fault codes in memory?
Is the turbo spooling and are you actually getting boost into the engine?
Are you sure that the cam and ignition timing are correct? 1 tooth off on the cam will make a big difference.

[xsaigen]

if i rev it slow past 2000 rpms and i push the pedal to the floor it revs fine untill it gets under 2000 again.