Crankcase Scavenging

[gsbill]

Hap, Why the personal attacks? I'm here to enjoy myself and maybe help others...Sorry you have such an issue with my posts...I just took your post for what it said...I dont want to argue.

The topic is well documented by very, very well known and accomplished racers and builders...I'm glad nothing is "wrong" with your bike...maybe the only issue was, that you didnt wash it often enough, hence the oil film build up...I dont expect you to care about me or my bikes or experience...

You seem vicious and defensive...I just dont get it...all because I stated that if your bike was covered with oil, something is wrong...My Goodness!

I know now that your views and more importantly, your motorcycle, are very much a way in which you measure yourself as a man and a person..so I will never again venture into discussion with you..dont want to risk it.

However I do wish you well and if you get the bug, call around to the guys racing fast bikes and do some research about crankcase scavenging...

Good day sir!

[lecroy]

Such a simple subject, so many ideas..... It has been fun reading it all.
Bill, you sure you drag? You know the saying, "Half the wheels twice the attitude". Your not fitting the mold .


"If Jake is going for 1/4 mile times then he should just put a crankcase filter on the vent off the top of his engine. That will prevent garbage from being pulled into the engine as it cools down."

If this were only allowed. At the track Jake runs at I am sure he could get away with it, but why bother. A 12 oz RubyRed, some holes, a zip tie and your done. Even has a nice lip for you to tie it to your frame. Very little weight as well. What more could you want? Jake, I would even drink one for you if you don't like the stuff.



2.1.2 CATCH CAN
Catch cans are mandatory on all motorcycles that do not utilize
a stock crankcase breather routing to the air box. Engines
with breather hose plumbed into a vacuum pump system also
require a catch can for catastrophic failure. The catch can
must be securely mounted. Use of suitable size hose clamps
is allowed; wire ties / zip ties are discouraged.

[gsbill]

[Hap Call]

I know now that your views and more importantly, your motorcycle, are very much a way in which you measure yourself as a man and a person..

You know nothing about me. I do know that you make statements about subjects that you know nothing about.

However I do wish you well and if you get the bug, call around to the guys racing fast bikes and do some research about crankcase scavenging...

You need to talk with the those guys...learn about inline 4 engines with 180 degree cranks and how they pressurize the case. Don't just learn that pro-stock bikes put vacuum pumps on the case...learn why they do it. You really don't understand what you are saying.

By the way, it was the "WTF" statement that set me off.

Lecroy, thanks for the clarification on the rules. I used a bottled water bottle on mine.

Hap

[gsbill]

An open post from Bill Fischbach:


I'd like to provide some good info in regards to crankcase venting, vacuum pumps etc., for everyones reading enjoyment! The principal applies to all 4 cycle motors, of any configuration. I hope to have GS inline bike info shortly to post. Thanks for reading!


ARC Crankcase Vacuum Systems

--------------------------------------------------------------------------------
BOLT ON HORSEPOWER! Precision machined from aluminum alloy, these breathers are the culmination of countless hours of R&D plus extensive bench and live testing. Do not be misled by knockoffs, they don't create the correct vacuum that increases horsepower. Do not underestimate the value of this product on a racing engine. Our dyno tests have shown a minimum 5% increase in horsepower in every motor we have tested just by bolting this thing on! Your engine becomes more efficient, especially at higher RPMs, improving acceleration and horsepower.

WE GUARANTEE AT LEAST A 5% GAIN IN HORSEPOWER!!!

Major features include:
? Eliminates vent lines and the need for catch cans.
? Helps stabilize rings for more consistency and horsepower.
? Prevents air from entering the crankcase saving horsepower.
? Helps eliminate oil leaks, blown crankcase gaskets and seals.
? Removes air from the crankcase and keeps it out, improving oil atomization and reducing drag.
? Triples oil life, saving you money and keeps the oil in the engine giving you greater protection from costly engine damage.

http://www.aerospacecomponents.com/vacp.htm

By producing high crankcase vacuum, horsepower is increased by improving ring seal and preventing blow-by, intake-charge contamination and detonation. Allows racers to run low-tension piston rings for less friction. More consistent and effective than header-mounted evacuation systems. Features billet aluminum housing, 12-AN fittings and integral mounting lugs to fit most engine applications. Parts available individually or in complete kit form.

http://www.fastbygast.com/Catagories/Products/description/vacuumii.asp

Ever wonder what that buzzing noise was coming from inside a Pro Stocker before they fired up? It's a Pro Stock secret... at least until we told everybody! That noise is coming from an electric vacuum pump. It's purpose is to evacuate the engine cases of unwanted pressures and make the piston rings seal better. The result is my favorite thing... HORSEPOWER! Well... almost my favorite thing.
Features:
Oil-less operation
Permanently lubricated bearings
Built-in cooling fan for constant use
Convenient mounting tabs
Closed housing and motor
Stainless valves and aluminum valve plate
Die cast aluminum head and diaphragm hold down plate
Balanced for smooth, low vibration operation
Long-life diaphragmHelps prevents oil leaks

GSBill...Big high HP motors(PSB motors) use GM vaccum pumps to suck any Built Pressure out of the crank case..The word is, its worth about 15 horsepower...Keep in mind this is on a 25k plus, 300hp motor.

GSBill...However I do wish you well and if you get the bug, call around to the guys racing fast bikes and do some research about crankcase scavenging...

Hap.....You need to talk with the those guys...learn about inline 4 engines with 180 degree cranks and how they pressurize the case. Don't just learn that pro-stock bikes put vacuum pumps on the case...learn why they do it. You really don't understand what you are saying.

BTW...I do get to occasionally hang out with those guys/gals.

[lecroy]

Some more info...

http://www.dragstuff.com/techarticles/vacuum-pumps.html

[Anonymous]

Currently my strret bike just has a K&N type filter on the rocker box vent. But if these pumps work would putting a hole into the exhaust to set up a venturi effect then conect the hose from the rocker box creat a big enough vacuum to make any difference
Even if it was only a few Bhp it would be cheap BHP 8O

[gsbill]

I put a feeler out over at Dragbike.com to gather more info on this subject...I'll have more to post soon....Check back!! Thanks for reading.


More info on crankcase scavenging

http://www.dragbike.com/forum/forum_posts.asp?TID=1326

... Bill, the benefits of a vacuum system are many. You can use less ring tension and the cylinder remains dry. The rings tend to stay down when the piston changes direction. The spinning and pumping piston/rod/crank mass has much less air~oil dynamic drag. As a side bonus the outside of the engine stays dry. No one runs withot it in any of the Pro NHRA or NASCAR normally aspirated classes. When you work out all the details it's worth three or more percent power production, with an increase in efficiency. Roland Tamaccio


Next One....



Bill, A couple of years ago I was looking at putting a vacuum pump on my streetcar so I rang an engineer from Castrol to ask him what he thought about it and if it would have any detrimental effects with street driving. He told me that it would probably be advantageous as it would help reduce foaming of the oil.

A vacuum pump is definately worth Horsepower. A friend had a V8 Cleveland that would go 12.00 every run. We put a vac pump on it and it went 11.80. The next run we took the belt off and it went 12.00.

Greig

[Anonymous]

I've ordered the scavenging kit from summit, it's made for V8's so I'll have a spare. I hope to dyno my bike soon to get a baseline before I do this, and I will test to see if it makes any difference. If anything for my street bike it will hopefully prevent oil leaks better. I'll keep you guys posted. Still trying to get pictures of my catch-can in the making.

[gsbill]

Excellent!! Keep us posted....

[Nerobro]

here I am almost wishing I had a twin now. A twin would give me an easy way to ensure low crankcase pressures. (put on a check valve, and when teh pistons go down, forcing air out of the crankcase, and then when they go up, the check valve will keep the air from re-entering... viola, low crankcase pressures)

As aformentioned, low crankcase pressures reduce foaming, control oil better, make the rings seal better, reduce pumping losses, increse horsepower by making the pistons see a greater pressure ratio... yes it's a good thing.

Now... just VENTILATING the crankcase.. doesn't provide much. If your rings aren't trash, it really isn't necessary to improve crankcase ventilation.

Small electric pumps are avilable for pulling a vaccum in the crankcase. You don't need much of one for a 700cc 4cyl.

Now the reason I didn't reply when this was first posted... was that he was suggesting the use of the exhaust to generate these low crankcase pressures. I've seen this done on high preformance car engines. But.... I don't see them generating MUCH of a vaccum. Pro-stock, Nascar, F1, and many other racing classes use dry sump systems, which artificially create a low pressure crankcase. Using the exhaust trick isn't nearly as effective, but... I"m sure provides "some" benifit.

If you were me. You'd use a small electric pump to do it. Or find some way of driving it off the crankshaft.

[Billy Ricks]

These pumps might be just what the doctor ordered. http://www.virtualpumps.com. They have the benefit of being very small and one line has a 5,000 hour life expectancy.

[gsbill]

Those are cool pumps...the link doesnt work...Loose the index.htm at the end

[Nerobro]

OOOOOOH.... Those pumps give me ideas.... I wonder what good it would do for my focus. Hmm.. maybe just hook it up to my GS :-)

[Billy Ricks]

The nice thing about the Virtual pumps is the size of fitting that it would take to hook up. 1/16" vacuum line is all it needs so drilling and tapping the filler cap is all it would take. Any idea of how much barometric pressure be best? If you look at the specs they list what they can pull.