bmod ehaust evac system

[phantomfab]

Hey everyone. I have a question concerning USRA Bmods. The question is being we are only allowed to run the evac system using a one way valve on the header and we can only use it on one side is there any advantage to running one. Also, if i do install one do i use the style that slips into a gromet and uses a breather such as the picture supplied or is it better/worse to weld in a fitting to the valve cover. Also wonder if a hose from the oil pan to the valve cover would make any difference as well. Thank you all.

[phantomfab]

since the picture wouldnt load I though I would just upload a link to a set like i was talking about.

http://www.jegs.com/i/JEGS-Performance- ... 0/10002/-1

[rebelrouser]

I have run this system for years in drag engines, Yes it will improve performance, how much? Maybe a couple HP, depends a lot on ring package, how good the oil pan is, etc. Best thing I like about the system is it reduces oil leaks. I use clear plastic hoses, and I can see real fast if blow by is getting excessive just by watching the amount of oil and water vapor in the hoses when engine is idling.

[MadBill]

There were some posts a while back re evac systems. I believe a SpeedTalker came up with an ultra-effective design that's in one of David Vizard's books, wherein the discharge tube is pointed straight downstream in the throat of the merge section. I want to say it pulled ~ 10" Hg...

[englertracing]

https://www.speed-talk.com/forum/viewtopic.ph ... 8&start=30
I think this is what Mad Bill is talking about.

I think it will be as good as it gets,
use a 1" hose to connect it to the valley. I would try to use it without a check valve,
or if your not into that use two check valves in parallel as to not restrict it.

Scavenging from the valve cover is not ideal as the air will be flowing counter the oil drainback
I think connecting it to the valley would be ideal, (not sure how that would work with whatever manifold you are using)
Connecting a hose from the pan to valve cover would have a similar effect

also don't expect earth shattering gains.

[MadBill]

https://www.speed-talk.com/forum/viewtopic.ph ... 8&start=30
I think this is what Mad Bill is talking about.

That's the one!

[geraldtson]

I don't care for them but if they help or fix something by all means. Someone used to make a bolt up (2 bolt) breather system designed more for the tall cast aluminum erson and such valve covers which could be converted to the evap breathers with a little hose and a couple clamps. Speedway-Allstar Performance- Erson may still carry them. The grommet style you referred to should work fine without all the welding.Depending on your valve covers. Wish i could do the picture thing on here,got a set of the bolt up on latemodel in shop. I need to tighten up!