compression gauge is cheap....and doing the test is simple....
Click here
doesnt need to be a super expensive one thats accurate....just need it to compare cylinder to cylinder.
let me know if you need directions on doing the compression test.

if in fact the head is lifting enough to let water in but not show on a compression test....it wont be long before the headgasket lets go....
lifting of the head is caused by two things...1. Headbolts arent strong enough and they are stretching (replace with ARP bolts) 2. To much timing and peak cylinder pressure is to high (shitty tuning)