Chevrolet Repair: 1955 chevy p/u, oil pressure sending unit, intake leaks

Question
I have a 55 chevy p/u that I just dropped a 383 engine into. I was trying to adjust the idle on the carb. and when I adjust it lower and hit the gas, the idle goes back up. I noticed there's an oil leak on the back of the engine, I'm guessing from the intake. Will this cause the engine to idle high no matter what if there's a leak from the intake? Also the oil pressure gage reads high, then it drops and stays low for a while. That's why I was wondering if the intake leaks, will this cause the problems I'm having? Any help would be appreciated.
Thanks,
Ronnie

Answer
Hey,

  An intake leak will give you idle problems only when it is leaking air.  If this is the case you would have a low unstable idle because the low pressure area by the idle ports  will not want to draw fuel.  Is there any way the Oil pressure sending unit is leaking?  This could cause a bad oil pressure reading if it is leaking through the center.  
 Do you have a Quadrajet on it?  If it still has the choke assembly make sure that the high idle cam is not engaging on the stop screw when the air is forced down through if the choke setting is not correct it could be tipping that cam over a bit.

Wayne