ok so iam looking at my old intake manifold and i see there is a lil runner on the intake gasket running to a hole on the block right its under the middlebolt hole what is this for cuz i just put my ho manifold on and it runs bad now so could someone please tell me what its for and what i need to do to the ho manifold????? thanks
 
 
i need to know what i have to do the the flange and gasket to make it work and what does the hole do?????????????
 
 
its the PCV(positive crankcase ventilation I believe) hole. Whatever gases build up inside the block, are fed into the Intake manifold to be burned off. Definitely not a good idea to block it off...
 
that small hole only applys vacuum to air/oil seperator on the block.......  as long as you run the long tube back into your intake system (the black hose that goes into the intake before the t/b) you'll be fine...... I've actualy ran the Air/Oil seperator vented to the air, and didnt have any problems.
SPD RCR Z - 
'02 Z24  420whp 
SLO GOAT  - 
'04 GTO 305whp 
W41 BOI - 
'78 Buick Opel Isuzu W41 Swap
