I Just received my new valve covers from Trick Marine. They look awesome. I want to install them tonight but I need to drill holes in them for the breathers before I install them.

Last week I bought what I thought was a set of billet air breathers but when I got them they are actually PCV valves. They are really cool looking but I don't know if I need them.

My old valve covers had a air breather on each cover . There was a hose form the breather to the flame arrester that that would help ventilate the gases in the block. I was looking to eliminate the need for these hoses to get a cleaner look on the motor.

So what is necessary for crank case ventilation on a marine application???

Would a set of breathes with filters on them with no hose to the flame arrester be fine .

Or can I use the two Cool looking PCV valves and run the hose to the flame arrestor. I don't mind doing this because the Billet valves look cooler than any breathers I found

Or use one breather and one PCV valve.

This is a 575 hp blown 454.

Thanks
Paul

My experience is to keep the hoses if you want a clean engine and bilge. The possible oil residue and condensation is not worth it in my opinion. We even had to extend the hoses higher in one application to keep the engine clean

Yeah , what he said. Without the vent hoses to get oil fumes and possible residue in the engine compartment.
Even more so with a blown engine
Try some braided stainless hose for dress up

Ditto on the hose. I even run a PCV on my blower motor now to keep condensation down in the cool months. No Thermostat.

you can use a billet over flow can and stainless hose ....
Like this...

With just the weak "suck" from a tube led near the arrester inlet, I don't think a real PCV valve will see enough vacuum to open, and the engine will function more in a "sealed" condition. (very no good)

I just picked up some plastic "fake PCVs" to allow free vent from cover through the tube up to the carb.

"Elbow-Breather" Quicksilver Part #97850 $2 ea.

or buy real PCVs and drill out guts.

Your going to need a baffle if you use a straight thru PCV valve. Make sure your Valve Covers have them built in.

You can also buy some MR Gasket baffled grommets for 5.00 pair. Part #720-5425. That's what I did.

Bob