[ArizonaGT]

Looking for input/comments/suggestions, particularly if you’re cammed up and turning lots of rpm.

 

[ArizonaGT]

Thanks fellas, I’ll give it a shot 😎

 

[ArizonaGT]

Get (or modify yours) collectors with evac bungs, pipe and a couple Thermactor anti-backfire valves and have at it....

View attachment 868075

That’s an option I’ve considered. What I really need to do is a belt drive vacuum pump, but that’s big bucks. At some point I have to ask myself “where does it end?”

Answer: it doesn’t 😜

 

[ArizonaGT]

It seems that at some level of increased performance, the original PCV valve spec does not flow enough air to relieve the crankcase of pressure. Mostly noticeable with any forced induction engine, but certainly a possibility on naturally aspirated ones too

That^ is exactly where I‘m at. There comes a point when your stuff simply doesn’t fit into the box it was originally intended for.
I just bought one of these Wagner valves, it’ll be here in a few days. It’s the quickest/easiest of the (reasonable😜) options I’m considering, so why not give it a shot.

I‘m just starting to gather parts for it, but I‘ve been bench racing a 363 build. That will require a lot more than just a slick PCV valve but I’m hopeful this Wagner deal gets me by until I’m actually swapping motors. Thanks all for your input 😎

 

[ArizonaGT]

FWIW, I‘m already running a separator/catch can. It’s one of those sealed Moroso cans, and it works well. I’ll update the thread once I have the chance to play with this new valve.

 

[ArizonaGT]

Whereas I exceed 7000 rpm every time out of the garage 😝 thus the need for more efficient crankcase evac. Primarily for high rpm ring seal, but also for oil leaks that I’m getting real tired of fixing.

 

[ArizonaGT]

More CI!

soon 😉

 

[ArizonaGT]

I’m reading the tech info. Tuning recommendations are (essentially) based on greater than/less than 10” idle vacuum. My deal makes 11” Hg, so I’m right on the in-between edge Lol 🤣

I haven’t been this excited to play with new/shiny stuff for a while. This is gonna be fun 👍

 

[ArizonaGT]

Ok, but why no leaks? Is it because of trapped pressure? Why is the pressure trapped if you have an "open" system with a breather cap on one side and a tube without a PVC on the other?

Without vacuum evacuation, the flow capacity is limited to the ID of the holes/grommets in the valve covers (and the breathers themselves), and it’ll build crankcase pressure. All that pressure has to go somewhere, often past the crankshaft seals, causing leaks. This usually isn’t a problem with typical street engines operating at typical street rpm as PCV systems were designed for that (relatively low cylinder and crankcase pressure)

I lost the ‘typical’ part long ago 😜

 

[ArizonaGT]

Of course, during "non-typical" driving, e.g. WOT (=typical for ArizonaGT as I understand it ), there's no vacuum evacuation, since there's (almost) no vacuum at the source (the intake manifold plenum) and the ventilation just bleeds of the pressure.

And that^
My current deal is fairly high strung, but my soon-to-be Dart 363 will embarrass this little Mexican 333 that I’m running now. The 363 will get an appropriate evac system for near zero manifold vacuum at WOT. It’ll need it 😉

 

[ArizonaGT]

I ordered it Monday, and it got here today 😎

 

[ArizonaGT]

If I were to install an air/oil separator in my car how/where would I get the oil back into the engine? New fitting on a rocker cover?

It doubles as a catch can. It does not re-circulate the accumulated oil, you just dump it periodically. Provided that the PCV valve is baffled properly, it doesn’t accumulate much oil, maybe an ounce or two every 500 -1000 miles.

I am not very happy with my power brakes and considering an electric vacuum pump. Perhaps a circuit using a PVC then through a separator and then using the pump to support the PVC and the brakes?

That^ sounds good to me, but maybe run that past Jim and/or other guys running Webers

 

[ArizonaGT]

Just a warning on seperators/catch cans: If you’re plumbing it between a PCV valve and a manifold vacuum source, do not use an open/vented separator. Manifold vacuum will pull air in through the vent which throws your fuel curves off (lean). They can also puke oil everywhere. They’re cheap for a reason; stay away from those.

 

[ArizonaGT]

@BlackStick

Just a thought… and I don’t mean to piss gasoline on a fire… but getting rid of that power brake booster would greatly simplify your specific deal.

 

[ArizonaGT]

Alright, enough of the d*ck measuring contest, you BOTH bring a lot to the table. More than the majority of members here. I learn a lot from you both, so don‘t go getting pissed at each other and then stop coming around 😊

 

[ArizonaGT]

View attachment 869156
Or 11meters/sec or ~24mph

Holy smokes, I was not expecting that^
LMAO 🤣

 

[ArizonaGT]

Back to the topic (ahem) 😜
After initial/baseline tuning of the PCV valve, I got a little carried away (Lol) with stuff I’ve been meaning to do, so I haven’t yet done any test ‘n tune. It might be another day or two, but I’ll update with more PCV data when I can

 

[ArizonaGT]

We need a popcorn emoji 🤪

 

[ArizonaGT]

Well then, since Woodchuck enjoys it so much

Strictly speaking, speed of air [ft/min] x volume of air [cubic feet] = something in [ft^4/min] but I'm sure you meant speed of air [ft/min] x flow area [sq ft] = volume flow [CFM]

The flow through the PCV valve is a function of the flow area and the pressure difference over the valve. A high air flow velocity through the carb and manifold does not necessarily create a low pressure at the PCV valve exit. Unless it is positioned in a low pressure wake area, which is possible.




I know, hence the "wise ass" comment

I’m frequently told I’m a “wise ass”. To which I always respond “it’s better than being a dumb ass.” 😜

 

[ArizonaGT]

This thread has taken an unexpected turn 🤣