I recently built a highly modded 3.4 it currently has about 150 hours

The past few weeks its smokes only under hard throttle and i have noticed coolant going down the past week

Engine has 3-5% leak down and 140-145psi threw out the engine....any help is appreciated

 

Sounds like a head gasket is leaking. Is the smoke a whitish color?

RBob.

 

Missing coolant, smoking... yup. Your engine is eating the coolant it seems.
Is your oil frothy? Wouldnt a leaking headgasket show up obviously on a compression test?

 

No the oil is still clear and looks great. It runs WAY to well to be a headgasket i think?

The smoke is white for sure

Could the intake gaskets be leaking?

 

The intake gasket would likely leak into the lifter galley and mix with the oil...
Have you pulled your plugs and inspected them? Maybe the intake gasket blew in to 1 cyl adjacent to the pass through.

 

Plugs look good no white spots from the coolant and no carbon build up.

Ill add its only when its hot