The T fitting on the intake manifold has a hose going to the rear that is most likely for a hydrovac brake system.
The short piece going towards the front is a PCV valve. There is supposed to be an "S" shaped piece of metal tubing (about 7/16" OD) going from the PCV valve to a 90 degree fitting in the top of the valve cover. The PCV valve is designed to be dismantled, cleaned and re-assembled.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12
'52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
| 
