my friends h/c/i vette had a similar problem it turned out that it need a breather cap for the valve cover....it was retarded as hell it made a wierd noise like the one u are describing so just start it up and take off the oil fill cap and see if its still there

 

"You did change the vally bolts right?.."


YES...new bolts went on....


not sure what the breather cap, and the oil fill cap have to do with it.

i pulled the oil fill cap off actually...the entire fill spout...and didn't notice anything.

 

Take a 2' length of 3/8" hose and put one end in your ear and the other end at the base of each injector. Chances are that an injector O-ring may have gotten displaced or nicked in the install & is leaking there.....the other place to look is on the rear of the intake where the brake booster hose & the small hose to the defrost diverter connect. The injector O-ring is my first suspect as it runs good yet.

Good Luck!

 

i've been meaning to track down some hose of pipe to do that...

i've double and triple checked the connections on the back of the intake.

it almost seems to be coming from the front of the engine. i even suspected something IN the engine or with the accessory drive....which is why i pulled the serp belt.

still nothing.