My friend's 460 has a PCV valve hooked up to vacuum at the carb base, AND a breather cap on the other valve cover, but the cap is the type with a hole on top; and you can really see the blow by at idle.
My 460 has both as well but the breather is the type where the vent is under the cap, venting at the base of the cap.
Are both necessary? Doesn't one negate the effect or effectiveness of the other?
Insight from 460 gurus would be appreciated.
