they go inside the vale cover and block any oilthat isbeing thrownat the fill hole.

 

u buy a kit to put the fill hole where u want it my hs auto teacher had those on his boss 347 motor he built

 

Or you could just keep the cap on when the car is running

 

with the Ford Racing ones, you have to get the holes cut in for oil and also need breather/ PCV valve. I bought mine second hand so it was all done. Apparently its not too hard to do and then you just get rubber gromets to fill the holes and plug your filler cap/ pcv/ breather straight in.

Ideally youd fit the same or longer baffles as the second set you posted. The baffles are supposed to stop oil from splashing into the breather/ pcv valve.

Have a look at a few pics...heaps of guys have them and they look great!

 

I'm sure if you look around you can find the ford racing valve covers that are already cut

 

Here, try these!! http://store.summitracing.com/partde...p;autoview=sku

 

^^^Cheers, I was looking into those with Red lettering and black background, and then I decided on this pair from NPD.

 

Oil will come through your breather and squirt oil directly into your PCV valve and ultimately your intake. All factory OHV engines have baffles in the valve covers, genius.

OHC engines don't need them due to how the top end is oiled.