Smoking problem, white smoke, help please...

[Walaboom]

Awhile back, I found out my coolant tank was dry, so I added coolant in there, not long after it I added it (about 2 weeks), it was almost empty again, so I added more coolant, but this time, I realize when I rev to over 3000 rpm, there is good amount of white smoke coming out of my exhaust...

I can also see small amount of bubble, maybe 2 bubbles per second coming out of my coolant tank. Oil is not looking milky/coffee and I dont see oil in the coolant tank or radiator when I open the radiator cap.

I have a KA-T w/ XS Engineering kit, currently only running 6.5 PSI.

Compression test, 18x 18x 18x 179, all pretty good reading for a car with 103k miles, therefore I doubt i have headgasket problem, but I am not so sure since it only smoke after rev over 3000 miles, therefore I want to ask some experts for advice.

Weird problem is, once the coolant in the coolant tank dry out (meaning you dont see coolant in the tank anymore) My car doesnt smoke anymore and the level of coolant in the radiator doesnt go down and engine temperature stays normal.

I just changed valve cover gasket, for both valve cover and spark plug seal. (Maybe I messed up here?)

Can anyone please help me and tell me what kind problem I might be having, thanks in advance.

1 more thing I have done recently, I changed spark plug, currently using BKR6E-11, gapping 0.3, not sure if this can be the cause, but I just added this info, so people that can help me diagnosis.

[C-Kwik]

try running a leak down test instead of a compression test. You are more likely to find small leaks in the headgasket with this test. If you have a compression tester, just hook up an air compressor to the hose instead of the gauge. Run it anywhere from 70-100 psi at the compressor. Look for bubbles in the cooling system.

I believe there is a device you can buy that does teh reverse as well. It replaces the radiator cap and allows you to add pressure. If the pressure starts to decrease then you have a leak. But given the loss of coolant, it sounds like you are leaking coolant somewhere.