PCV Valve?
 

On the 90 SOHC BP 1.8 there is a pcv valve that connects between the intake manifold and the rocker cover. If you remove this PCV valve and plug the end on the intake manifold and put a filter on the rocker cover will this effect the engine at all? that is in a bad way?.

Also can anyone tell me what the hose that connects between the intake tube and the rocker cover is designed to do?. I read in a Hot 4s magazine that it can put oil deposits inside the throttle body and can eventually put carbon deposits on top of your pistons.

Thanks guys.

if it's what i think your talking about, your pcv valve prevents carbon monoxide and unburned hydrocarbons from entering the atmosphere, basically, recycling it to be expelled through your engine and eventually flushed out by your exhaust system. there was talk before about putting a 'breather' fitting on the valve cover inplace of the pcv valve, and the concensus was it provides no benefit to you... so i don't know
peace

When your fuel combusts above your pistons to force them down, some of the exploded gasses blow by the piston rings and make it down into the crankcase (below the pistons).

You don't want these gasses mixing with the oil in your crankcase, because it causes the oil to break down and lose its lubricative properties. Therefore, these gasses need to be vented. In the old days, these gasses were vented to the atmosphere, but in these pollution-free times, they are recirculated through the engine to be burned again.

I suppose that since these partially-combusted gasses are not very rich in oxygen, they could decrease your performance. I don't know how much of a difference you'll notice by removing it, though.

Since the PCV valve is part of your emissions system, your state's inspection process might not be too happy with this mod.

I believe the tube that connects the intake tube to the rocker cover is intended to equalize the pressure differential caused by the PCV system.