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I think I would do PCV on opposing corners and the fresh air caps at the two opposites, IF there is enough vacuum to support such a system.
 

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1965 2+2 Vintage Burgundy A-code C4
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So why not something similar to the b302 system?
 

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Catch can not an option?
 

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What are you looking to accomplish? At high rpm/throttle opening you're only going to have so much vacuum available and, since the PCV system is, in itself, a "controlled vacuum leak", you'll further reduce the capability to evacuate excess blow-by. There's a reason why folks use exhaust-generated evacuation..... it works when vacuum is limited and especially when power-adders such as forced induction result in excessive blow-by under power.
 

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I thought the pcv was supposed to be on opposite sides so as to draw fresh air not just to the valve cover area but through the crankcase.
 

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1965 Mustang GT. 11.898 @ 113.646, all motor, three pedals
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If you’re looking to control/minimize ring flutter, no PCV system will do that, regardless of how it’s plumed. You’re in vacuum/evac pump territory.
 

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1965 Mustang GT. 11.898 @ 113.646, all motor, three pedals
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Although the collector evac deals work decent enough, for what they are.
 

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If you’re looking to control/minimize ring flutter, no PCV system will do that, regardless of how it’s plumed. You’re in vacuum/evac pump territory.
Correct. The pumps help promote ring seal and thus gives increases of 10+ HP, with lighter than stock tension rings offering up to about a 30 HP increase.) The pump drag is a non-issue as the pumps offer virtually zero resistance (meaning we can intentially leave the drive belt quite loose to reduce side load pull on the bearings.) Mine's a GZ, has seen numerous 8300rpm runs, and is also street friendly. Unfortunately the cost to play isn't cheap and typically start in the $1K range.

A side issue is when you keep negative pressure in the crankcase, oil leaks are virtually a non-issue and the required puke tank helps keep the track clean for the next guy.
 

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I've always wondered if the old Thermactor smog pump would work for crankcase evacuation. Just a simple vane type setup. So long as it wasn't sucking water or globs of oil, it should pull a few inches of vacuum, right?
 

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Discussion Starter · #13 ·
I've always wondered if the old Thermactor smog pump would work for crankcase evacuation. Just a simple vane type setup. So long as it wasn't sucking water or globs of oil, it should pull a few inches of vacuum, right?
A vacuum pump would work but it needs to be electric for high rpm use and thats just more weight in the front
 

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Discussion Starter · #14 ·
So why not something similar to the b302 system?
It doesnt really rid the crankcase of contamination. For racing all that matters is winning the race. the oil is changed after every race. this is for street driving and roadrace track.
 

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Discussion Starter · #16 ·
I thought the pcv was supposed to be on opposite sides so as to draw fresh air not just to the valve cover area but through the crankcase.
Right. A pcv valve and breather cap on the same valve cover doesnt do anything. The pcv valve sucks air from the cap across the inside of the valve cover but doesnt suck fro3m the crankcase.
 

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Back in the '90's I put 2 PCV valves on my 351W to try and control blowby, can't remember if I did same VC or opposite but while driving 50mph both closed at the same time causing airlock, engine shut off and I coasted to a stop not knowing what happened. A friend showed up, noticed the 2 PCV's and pulled one, gasping vacuum sound and I was back running again o_O
 
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Why wont the Wagner PCV valve work for a high rpm engine?

You are really overthinking this - the breather will simply vent at high rpm if pressure in the crank case goes positive .PCV will maintain negative pressure the rest of the time.

Otherwise as said, run a belt driven vac pump. Best solution outside of a dry sump.
 

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Discussion Starter · #19 · (Edited)
Why wont the Wagner PCV valve work for a high rpm engine?

You are really overthinking this - the breather will simply vent at high rpm if pressure in the crank case goes positive .PCV will maintain negative pressure the rest of the time.

Otherwise as said, run a belt driven vac pump. Best solution outside of a dry sump.
I contacted Wagner and its not a high rpm race piece. Race engines dont use a pcv so why design one that nobody but me would by. i drive race engines on the street, for daily driver, etc. I'm techincally a hard core biker except preference is a Campbells chicken noodle suoped mustang and other fords. The breather system isnt that great for street use. the pcv is a great thing.
 

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just TL;DR: there's a finite amount of vacuum available, whether it's low or high RPM. The valves are calibrated for a specific amount of flow. If you run two valves, but have the same amount of suction, it's not going to flow twice as much - it will simply create a vacuum leak at low and midrange RPMs, and do about the same at high RPMs as a single hose/single vent setup.
 
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