Yeah.  I remember the previous group buy.  I didn't get in on that one, but I'm ready to give it a try now. 
Do you like yours?

Michael H. wrote:

Yeah.  I remember the previous group buy.  I didn't get in on that one, but I'm ready to give it a try now. 
Do you like yours?

I actually haven't had a chance to even use one of them yet.  There's one in my 331 that's on an engine stand waiting a home in my '89 GT, but when my Diesel truck went down the shop got clogged up with parts for it and I can't get the GT down from the lift to work on it.  The 347 for my '67 is also getting one, but its just a shortblock.  The 3rd one is for my Blazer (383), but that's even farther back on the priority list (until my son decides its what he wants to drive when he gets his license in another 2 years anyway).  So a series of priority changes has prevented me from even being able to mess with one the the valves yet.  Having two kids and their seemingly infinite activities also doesn't help.  
 

I agree there are some major questions in that chart.  If the engine has breathers on it, how is the crankcase under pressure all the time?  Breathers install in the valve covers like the PCV does.  The crankcase may not be under vacuum with breathers, but its not under pressure either (other than atmospheric pressure).  

Competitor's valve, and stock A, B, and C is also misleading because are all those valves designed specifically for the engine being tested?  Doubtful.  If one stock replacement is 58% better than another (assuming they are for the same engine/vehicle) something is drastically wrong with the way they are being made.  That's kind of like saying this stock replacement coil throws 58% more spark energy than this other one.  Sure there are quality variations, but aftermarket parts are still designed, in theory, to a common standard, making that much variation seem unlikely.  10-15% I might buy.  

I would definitely not gut the PCV valve though.  If you want vacuum all the time run a vacuum pump or pan evac system.  The PCV also usually goes directly into the intake or a spacer under the carb, meaning that without a check valve you would create a massive vacuum leak by in effect not running a PCV valve.  Furthermore, if the intake ever sees pressure you are then pressurizing the crankcase (probably not an issue on an NA engine, but for anything boosted this will lead to oil leaks).   Another better option would be to run a catch can.  Though there is more plumbing on such a setup.  

I think the seeming absurdity of the chart aside there is still an advantage to being able to adjust the PCV system to a modified engine.  Like with most things stock parts go well with stock engines, and I've seen a lot of posts with guys who were very happy with the difference the M/E Wagner valve made in the way their modified engine ran.  

That's definitely 100% correct with respect to data.  The first thing you learn in any statistics class is that statistics are used to present data.  The second thing you learn is that the manipulation of the data set leads to most statistics being misleading.  

I would add this though, did you try to run the stock PCV with the MSD Atomic 2 EFI?  Because it begs the question how the engine would have run, since you had to adjust the M/E Wagner valve significantly.  Possibly the stock valve, which couldn't be adjusted would have led to poor running.  Just speculating, but in the interest of a fair comparison it's important to point our that we only have half the data.  

Price and a picture?