Valve cover questions ?

[434 nova]

Can you run valve covers without breather holes or do you need breather holes? I am not running a vacuum pump or anything like that.

[Craig W.]

The engine needs to breath. Either use a vacuum pump, header evac or valve cover breathers. A sealed up crank case is an oil leaking in the making and will hurt power.

[supernova]

Yes you need breathers, if not pressure will build inside the block and could push out seals and gaskets to start with.

[434 nova]

Thanks guys, I will defently be buying fabricated valve cover with breather holes.

[sc racing]

I was going to use a 1/2" NPT hole that was already in the valley part of my intake and run a #10 hose to a breather tank because I couldnt weld any bungs on my valve covers without messing them up they have some type of clear anodizing on them and I didnt want to grind it off. I didnt want to use the push in breathers so I got the screw in type and just drilled holes. Theses brethers have the check valve inside them so I dont have to run the diverter valve on the colletor just the pipe.