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Yea, I'm sure your setup is the way to go since there's pressure in your intake - if it's a line I'm assuming there is no collection canister but if done right it probably doesn't need one, as long as the rings are doing their job - is your setup like an ejector where the Turbo exhaust actually creates a small vacuum on the crankcase ? Hows your oil consumption ? Thanks Doug -
 

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Doug,
Would you have a photo or 2 of your crankcase vent system? This idea intrigues me, and I would love to incorporate this on my NA muscle. Certainly better than the stock crankcase vent system.
John
 

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Doug,
Would you have a photo or 2 of your crankcase vent system? This idea intrigues me, and I would love to incorporate this on my NA muscle. Certainly better than the stock crankcase vent system.
John
John,

I THINK he is describing the old big block trick of welding a nipple at an angle onto the down pipe with a hose running from the breather on the valve cover(s).

This is what I am referring to (correct me if I am wrong, but this has been done for eons and does work assuming you have enough exhaust flow to create enough vac): https://www.summitracing.com/parts/sum-120108?seid=srese1&cm_mmc=pla-google-_-shopping-_-srese1-_-summit-racing&gclid=Cj0KCQjws5HlBRDIARIsAOomqA0QvM8cqZog-xkQoYrG7vrpqG8Zm41mOVbd938XIuUWAz0IMaYB1R4aAjCWEALw_wcB
 

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Discussion Starter #85
yes those are the parts, but you only need one threaded nipple and one , one way valve. It does have enough vacuum after the turbo ( or in the collector of a two into one pipe).
 

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Interesting......
Dont know how well that would work on a NA engine. Have my doubts
Most exhaust systems have back pressure in them and some bike tuners actually have tested this. In an aft turbo, there is none so it's apples and oranges. Hoses, one way valve and a catch can is the better option in my view. Even just one way valving in the stock system will reduce oil carry over into the box.
Ron
 

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Discussion Starter #88
I believe NHRA ProStocks are the baddest NA motors on the planet. They all utilize crankcase evacuation vacuum pumps to suck air out of the crankcase ( lots of Sportsman racers do too). At 5000 rpm, simply moving the air under the piston from one side of the motor to the other is happening over 80 times a second. Anything you can get out is a benefit.
 

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I believe NHRA ProStocks are the baddest NA motors on the planet. They all utilize crankcase evacuation vacuum pumps to suck air out of the crankcase ( lots of Sportsman racers do too). At 5000 rpm, simply moving the air under the piston from one side of the motor to the other is happening over 80 times a second. Anything you can get out is a benefit.
Vacuum pumps. They do that for two reasons I know. To reduce air under the piston on the down stroke which removes some resistance that comes from the under side of the piston trying to run into this air and compress it
. Secondly for better ring seal. The negative pressure helps keep the rings planted on the lower land of the piston. Win win results.
Regarding our Revolutions. Adding one way valving to the standard breather routing creating a static to slight negative in the case has been proven to add a couple of ponies. Less oil barf out of the hose(s) is also a side benefit. As the current Revolution stands the breather system creates slight positive pressure pulses. There is room for improvement.
Ron
 

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Well, how do we improve it ? Discussion ?
Well, what's kept me from one way valving the crankcase is an unknown in the design. Take any single cyl or variation of a v twin and just about all of them have a one way valve in them to bring the case to static or slight vac. The unknown here is why wasn't it done with the Revolution. Is there some underlying design intent regarding long term lubrication in some part of the engine or trans that a one way case venting could screw up some? I've not come up with the answer yet.
Ron
 

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Well, what's kept me from one way valving the crankcase is an unknown in the design.
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A quick search located a few threads where other forum members tried check valves to improve on the OEM crankcase vent system; e.g. this one.
In this thread an aftermarket oil catch can, check valves, and the MotoHooligan airbox are all discussed. (Ron, you posted in this thread).
 

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A quick search located a few threads where other forum members tried check valves to improve on the OEM crankcase vent system; e.g. this one.
In this thread an aftermarket oil catch can, check valves, and the MotoHooligan airbox are all discussed. (Ron, you posted in this thread).
Thanks for reminding me about repeating myself.:)
I did however come up with a one way breather valve head that replaced the existing cansister cap which a hose could exit out the bottom of the breather box and either to a catch can or just under the bike. Got as far as a quick sketch but no actual prints. I'm retired now so no machine shop available and not a lot of interest to pursue it. Me personally I get very little oil in the box but I do see some carbon on the intake valves from oil misting.
Ron
 

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Interesting post here on detonation; https://www.enginelabs.com/engine-tech/misunderstood-causes-of-detonation-in-high-performance-applications/ Awhile back we had some discussion on the Delco Ion sensing algorithm. I still feel I'm better off to build a tune that doesn't detonate rather than band aid a bad tune. Comments ?
Agreed, but without a knock detection system in place how will you detect said knock to tune it out?

Reading plugs?
"Listening"?

See where I am going with this? I can elaborate much more, but the point is not to let the knock detection system of choice "save" you, but rather provide a critical piece of data to review and then work around (i.e. I had some knock counts at load X so I need to cut back timing there and add some fuel). No data? No way you will fight the knock effectively (or safely). At best you would be guessing.
 

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Discussion Starter #99
Freudie, We're talking chicken vs the egg, I know. I'd use the algorithm if it was available, but its not. So either option requires a work around, right ? If I data log detonation, I still have to accurately figure out the cause to correct it. The link gives some great cause/effect explanations. Please keep posting & making recommendations, the dialog is great.
 

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Discussion Starter #100
I had a thread about water/meth injection in another header. Has anyone built a system ? By injecting pre-compressor it seems we could lower intake air temps to increase charge density and increase anti knock potential from the mixture.
 
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