I have the ZZ4 engine and its only got about 200 miles on it. I dont know if this is normal or not but cold the engine is at about 50 psi in oil pressure at idle. But as it gets heated up the engine drops to about 27 psi? I just had to re-adjust the timing today to get it right on and this is the first time I have seen the pressure drop this low. Is this normal or is there something wrong?