Coolest induction system video ever!

[shady]

it always amazed me that how well & long an engine runs when starting it by just pouring gas down the carb throats when the carb is dry. just raw gas sitting in the intake.

[XR7]

I was impressed when I saw this the first time as well. What caught my eye the most was just what Jay was talking about, the "ram effect" of the pulses in the runner when it got into the "sweet spot" for RPM. Basically ram tuning or 3rd harmonic tuning, whatever you want to call it... it was pretty evident with the finger getting pulled down hard at that certain RPM where the runner length was correct for that RPM. This is how race engines make more power and have well over 100% volumetric efficiency.

I too was amazed at the amount of fuel climbing the plenum wall and washing around everywhere. I thought it would be more of a mist or the fuel would be more of a "fog" being mixed better with the air (A/F ratio).

I am sure the plenum shape couldn't be more like normal just because it was made up out of flat sheet and more of an experiment for testing.

Certainly and eye opener!

[Heo]

In the 70s 80s Volvo R-Sport
sold an intake for 36-36 Weber.
For the B20 Engine,that had
"Finns" on the plenum floor
To make a mist of the Liquid
Fuel it was said
It was the only 36-36 intake
That worked god
Other without the finns was hard
To tune over the Rpm span
Sputered and hesitated.on Low
Rpm

[westcoastgalaxie]

That fuel separation is one of those concepts that make you go duh after seeing it live like this. You stand in a hurricane you get wet. No surprise oems went to EFI, then DI. Sure wasnt for the sake of making things complicated. You can bet they did similar experiments.

With all that said still impressive the power and efficiency that can be achieved with a simple carb. That kind of out of the box thinking may not be that unorthodox, sounds like good ol problem solving to me. Identify a problem, identify how a given system works to see what affects your problem and solve. There will be more than one way to skin the cat. Not always simple but always effective.

[babybolt]

"Put another way, I'd like to see the result of a similar tunnel ram test but with throttle bodies that only handle air and the fuel is added directly to the runners via injectors.....obviously EFI.   
If most of that wild fuel separation in the plenum now goes away, wouldn't we expect a fair hp increase, a sharper throttle, etc?"

With fuel injectors, I would bet that fuel would still be sucked back into the plenum and lay on the bottom, if not coat the sides of the plenum after awhile. 

[Qikbbstang]

It was decades ago, but it was the biggest screw-up I ever had anything to do with in an industrial account. A paper mill requested I furnish an air-intake filter for a large Joy piston type air compressor. The inlet flange was to be a 14" ASME. I can't recall the CFM but the filter housing and piping were required to be an all stainless steel. I contacted my supplier and delivered what essentially looked like a giant mushroom that held a huge single cylindrical filter element. About a week after it was installed I was called to the mill to look at the filter housing that had a experienced cracking in numerous areas. Fortunately we had recently hired a new mgr at another location that came from the air compressor market. He advised me to give him the bore, stroke, pipe size, rpm and length of intake piping. I faxed him the info and called to see if he had received it. He'd already done the calculations and advised the "critical length" zone was 10'-14' and the filter housing was situated dead in the middle of where it should not be. I advised my customer to either shorten or lengthen the inlet piping x-many feet, returned the filter housing to the mfg who rebuilt it and returned it rush and it worked happily for decades. You'll notice in the PDF they even mention valve breakage.
    When 14" pipe and large filter housings crack from intake pulses you can't help but think: "Man if you could tune to take advantage of those pulses". 

http://www.industrialairpower.com/wp-content/uploads/2008/10/joy-wn-compressor.jpg

http://docs.lib.purdue.edu/cgi/viewcontent.cgi?article=1110&context=icec&sei-redir=1&referer=http%3A%2F%2Fwww.bing.com%2Fsearch%3Fq%3Dcritical%2Blength%2Bcompressor%26src%3DIE-SearchBox%26FORM%3DIENTTR%26conversationid%3D#search=%22critical%20length%20compressor%22

[XR7]

Here is an interview video with Jon Kasse. It first talks about engine masters for a while, then about the "finger in the runner" video posted above. Pretty interesting...

https://www.youtube.com/watch?v=69pr4_DRbZY

[Dumpling]

Would it help if you ran some sort of beaters in that huge plenum to keep the fuel aerated?  Two Kitchen aid beaters at each end of the box, 4 total, literally mixing things up, electric powered?

Would DI engines still have fuel backwashing up the intake ports out of the chamber?

[Qikbbstang]

Smokey Yunick refered to the turbo on his 50+mpg fuel efficient car as a homogenizer................... 

Years ago there was a company that sold gaskets with woven wire cloth spanning the ports. A flat section of cloth would certainly cause restriction, but deeply bowled cloth could arguably offer minimum restriction and still break up fuel droplets 

http://www.hotrod.com/how-to/engine/hrdp-1009-what-ever-happened-to-smokeys-hot-vapor-engine/

[machoneman]

Would it help if you ran some sort of beaters in that huge plenum to keep the fuel aerated?  Two Kitchen aid beaters at each end of the box, 4 total, literally mixing things up, electric powered?

Would DI engines still have fuel backwashing up the intake ports out of the chamber?

Yes, I believe even with direct port injection, some backwashing would occur. Consider Kaase's finger as it is pulled up AND down as the valve opens and closes. Pulsing is an effect of the valve's opening and closing at a rapid rate. When the valve is snapped shut, that column of air/fuel it still moving towards the backside of the valve at high speed. The collision to some extent causes backflow (or back wash) until the valve reopens.

As Jay mentioned earlier on "....What gets me is the strength of the pulses; I had no idea they were that strong.  When I switched runner lengths of the intake on my SOHC, I saw a huge power increase at the engine speed of interest, so there was evidence that the induction tuning really has a major effect.  But to see Jon's finger snapping back and forth like that in the port really drives that point home."

Adding longer or shorter ram tubes on an fuel injected engine, like his SOHC in the '63 Galaxie, is a well know tuning trick to essentially move the rpm band up or down, short being up, long being down. However, I never really thought about how a long ram tube (for low-middle range strength) would coincidentally keep more of the air/fuel suspension, and not just the air, closer to the intake valve. I'd venture that if the runners in the plexi-box were say twice as long as depicted even less of a sheet or wave of raw fuel would accumulate in the plenum section.

And yes, Yunick is still long dead as are many of his disproven theories. The good theories and facts did survive him but have since been supplanted or added to by facts modern race builders like Roush, Penske, Kaase and other giants of the trade have proven time and again.   

[gdaddy01]

I wonder if that is some of the thinking behind the " McGee " valves from years gone by . google mcgee valve .

[turbohunter]

Years ago there was a company that sold gaskets with woven wire cloth spanning the ports.

Don't look now but that's been prototyped and in development again.

[machoneman]

One of the greatest scams of all time, the wire mesh over the intake plenum. It's right up there with Yunick's error (or scam?) on the long rod theory. Here's what noted Ford Pro Stock engine designer and all-around drag race engine expert Darin Morgan has to say, with facts backing him up:

People put WAY to much importance on this preconceived " ideal rod ratio" idea. Rod ratio is not a primary consideration when designing an engine. You get the deck as short as possible so the piston does not come out of the bore. That gives you better manifolding which will make ten times the power any " ideal rod ratio" would net you. You shorten the pushrod and make the valve train stable above 9000rpm. You make the piston ring package as compact as possible to get the pin as high as possible and that will make for a light weight, balanced (not top heavy) piston design, THEN you decide what rod connects the piston to the crank. Its not magic, its simple mechanics. People look at what Smokey Yunick said and they take it out of context in my opinion. He said you should put the longest rod YOU CAN not the longest rod YOU CAN CRAM JAM OR MANIPULATE into the engine. I see people all the time screw up the engine combination to facilitate some preconceived ideal rod ratio and they wonder why the thing wont turn up and make power. The difference in the GM 358 NASCAR test engine from 5.250 inch long rods to 6.1 inch long rods was maybe 2ft/lbs and 2 HP. Not much to worry about. That satisfied the GM engineers that there is nothing there. Does a short rod make more TQ? Does a long rod make more top end power? It probably does but its such an insignificant amount, its not even worth messing with! If there was a major advantage or power gain in this, it would have been proven a long time ago and we could all put this to rest but no one has. I wonder why??

Darin Morgan
R&D-Cylinder Head Dept.
Reher-Morrison Racing Engines
1120 Enterprise Place
Arlington Texas 76001
817-467-7171
FAX-468-3147

 Visit our web site at
http://www.rehermorrison.com
Darin Morgan   

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[turbohunter]

I'm confused Bob.
Why argue wire mesh with a rod length comment?

And I'm certainly nowhere close to as experienced as Darin Morgan but rod length (it would seem to me) IS a primary consideration when designing your engine. Piston height is kinda important no?

Sorry if we're heading off the intended thread path.

[machoneman]

I'm not conflating the two at all. Wire mesh stuff was right up there with magnetic fuel lines magically improving mileage. Debunked as were many other alleged mileage improver ideas.

Rod length is also one of those over-thought topics that also allegedly reduced reversion in an intake tract per Kaase's example plexi-box, dramatically increased hp and cured baldness as well! Morgan and others have since proved otherwise. If it's 50th on his list as he stated elsewhere in those wonderful Reher-Morrison racing engine articles, it should be the same on our "list." Just sayin'...... 

Point is: the reversion in the Kaase intake tract appears to be present regardless of rod length and a few other factors common to many engines. Perhaps a much longer runner length dampens the collection of sheets and drops in a common plenum.  Save for more testing, we don't really know is this is the case.

http://rehermorrison.com/category/tech-talk/