Hi I just received my Offenhauser valve covers from Summit for my 401 and i have to say they look awesome!!! However there is one thing i dont understand: On the one valve cover side there is the hole for the oilfilter, but on the other there is no hole for the hose that is going to the carb. Do i have to drill a hole for this hose or can i put it on without any filter or hose? I thought the covers come ready to install. please take a look on the pics. Thanks and happy easter Alex
Alex, Those valve cover may fit a lot of different engine displacements and years of production, so many times the aftermarket manufacturer may not open up the holes on a valve cover so the owner can do what they would like. Some of the older nailheads that ran road draft tubes instead of a PCV system may only have an oil fill provision on one valve cover. Hole or not, those are GREAT looking valve covers! Tim
You should be able to go to a speed shop and buy a breather or grommet that will go into the hole on the valve cover and has an opening in the center for a push in pcv valve. I also think there are 'breathers' that have the pcv style fitting built right in. Those and nearly every aftermarket pair of valve covers typically have the minimum amount of holes drilled in them from the factory. Most 'hot rodders' want the cleanest look possible and will put the pcv valve in other locations such as the valley cover etc... good luck,
Some of the 50's Nailheads came with the breather in the valley pan....so that would be a good option for you if you don't want to put a hole in the other valve cover. And yes, you should have one breather and another for pcv....for air in/air out.
Yes-those are nice looking covers. A breather/oil filler with a PCV provision by itself wouldn't really work-OK if there was a breather on one valve cover and closed at the other with PVC itself. You want to pull the blowby gases across or thru the engine for reburn. Probably the 430/455 central location is a tad better and tidy-the PCV is nearer to most of the blowby gases. But that also makes it near to the rotating assembly and heavy oil spray. So, using the nailhead valley pan would be good as long as there is some kind of baffle (as the 455valley pan does) used to keep that spray being pulled right into the PCV-showing up as heavy oil consumption
On the stock valley pans there is still a road draft tube boss in the pan and you could always drill it open for the PCV grommet and weld a baffle box to the underside sheild it from direct oil spray.
Som e of the push in grommets availible have 'baffling' molded into them. I have one of these on the 327 in the wifes 54 Chevy. The pcv valve pushes into the top part and then the 'baffling' makes up the lower part. I may have mis-spoke when I said a 'breather with provision for pcv valve' I should have said a twist in 'cap' with provisions. And, yes-you should have air flowing in one side and the pcv valve on the other side (or valley cover)I don't think there is much more 'splash' oil in the valley than the rocker area but I have never run a motor with the valley cover off....
