ok my motor runs fine and pulls hard with no smoke, but all of the sudden after i put in gsr pistons (in a b16), there is very little vacuum (like 5-6 at idle, which is fairly steady with a little bounce) but no noticeable affect on anything else. im almost affraid to borrow a compression tester but i dont see how it could be low enough to cause that little vacuum. any suggestions on what to check? and yes all the hoses are hooked up, im thinking somehow the iac could be doing it or something, i really dont know

 

i really dont get it...its flashlight time, something has to be unhooked

 

yeah but the thing is that no gaskets have been changed, and nothing is unhooked or cracked, etc. if it hadnt happened right after the rebuild i wouldnt worry and i wouldve been swapping gaskets, etc already (which ill be doing tomorrow most likely)