Re: Poor compression - cause? Updated
Posted: Fri Jul 17, 2020 12:36 am
The modified McCoy Stromberg to Weber conversion heads do not have the standard breather oil knock
out chamber, as this machined off as part of the conversion and for some reason yours is similar. Do you know the source of your head? QED many years ago developed a similar head conversion that may also have removed the breather box . I have never seen details of their conversion but i understand it had welded in inlets. They sold it for a short while in the late 80's early 90's before they started casting their own new heads
Putting a breather on the front of the cam cover is the normal way to deal with not having the standard breather chamber arrangement. The standard breather chamber does not really contribute to head oil drainage and removing it does not affect it.
If wanting to use the engine block breather rather than add one to the cam cover then you need to set up something like Ford used so the oil is knocked out of the breather gas flow and drains back into the engine
cheers
Rohan
out chamber, as this machined off as part of the conversion and for some reason yours is similar. Do you know the source of your head? QED many years ago developed a similar head conversion that may also have removed the breather box . I have never seen details of their conversion but i understand it had welded in inlets. They sold it for a short while in the late 80's early 90's before they started casting their own new heads
Putting a breather on the front of the cam cover is the normal way to deal with not having the standard breather chamber arrangement. The standard breather chamber does not really contribute to head oil drainage and removing it does not affect it.
If wanting to use the engine block breather rather than add one to the cam cover then you need to set up something like Ford used so the oil is knocked out of the breather gas flow and drains back into the engine
cheers
Rohan