Induction and Airflow question

[Anonymous]

What effect would introducing a stream of pressurized air into the induction airflow produce?

This pressurized airflow would not REPLACE, but be IN ADDITION TO the engine's normal aspiration (I.E. atmospheric pressure).

The stream would be introduced into the air cleaner snorkel (of a car equipped w/ standard factory cool air induction tubing), it's flow directed toward the carb.

Not a pencil-thin stream of pressurized air, but from a source of 7/8" diameter (approx. 1/3 the a/c snorkel opening size).

The flow would not be present at idle, only when the throttle is open, and it's volume would increase with engine RPM.

Theory: While I am not a scientist or physics major, it seems to me that since an engine is really just a type of air pump, ANY increase in the amount of air that is moving through the engine would be beneficial.

Since a normally-aspirated engine's intake charge is pushed into the cylinders via nothing more than atmospheric pressure, the system described above would be beneficial as it introduces a flow of air into the induction system at a pressure higher than that of the atmosphere.

Or is any possible benefit lost or diminished due to the fact that the air induction tubing is open to the atmosphere at one end?

Or is there benefit present simply due to the addition of a directed, rapidly moving flow of air towards the carb?

What say you?
Your thoughts and input are welcome...

 

[Anonymous]

sounds like a supercharger or a turbocharger to me.

 

[Anonymous]

How about Ram-Air?!!

The problems with the 7/8" hose is that at high revs, where you are making decent horsepower, you need an enormous amount of air volume to make an appreciable difference in performance, and secondly, where is this air coming from? The use of a supercharger, which is designed for these applications is a much better way of increasing port velocity. Ram-air helps, but only at high vehicle speeds.

 

[StrangeRanger]

You'd have to seal up the carb bonnet when you turn on the high pressure air supply or nearly all the air would just vent to atmosphere. To feed even a small engine, you're looking at a lot of air. A 200 CID engine at 6000 RPM and a volumetric efficiency of 80% uses 277 CFM of air. Since you're not talking about a supercharger, I'm assuming you'd be using an on-board tank. Ignoring all the thermal losses and inefficiencies (mostly because they're too much trouble to work out) to provide enough air for a 6 PSI boost you'd need to supply 390 CFM. To make the system worthwhile, you'd probably want a tank that could provide a minimum of 30 seconds of sustained airflow at this rate or 195 cubic feet of air @ 1.4 atmospheres, something like 275 cu. ft. at one atmosphere. Assuming that you can pressurize your tank to 6 atmospheres or 88 PSI you'd need a tank no smaller than 275/6 = 46 cu. ft. or 344 gallons. In actuality it would have to be quite a bit bigger, say 400 gallons. You could fit it in the bed of a pickup, but the weight and aerodynamic drag would cancel a lot or maybe all of the performance gains. You could go to a high pressure air supply with a step-down regulator and greatly reduce the size of the tank, but such a system would be EXTREMELY dangerous. High pressure gas tanks become ballistic missiles if the regulators are broken off like in a minor fender bender.

FWIW the air tank system was tried on either a top fuel or a funny car back in the 70s (don't remember whose car though) and found wanting. But they were only looking for a 6 second supply at 500 cu. in and maybe 8000 RPM and some stratospheric amount of boost, very different from a street application.

 

[Anonymous]

StrangeRanger-
You bring up interesting points in your response. But my system doesn't use a storage tank, and is designed to enhance only low to midrange RPM performance. Perhaps the info below will provide further food for thought...

SnowDragon-
Yes, it does sound like a super- or turbo-charger, but the system isn't sealed, it is open to the atmosphere at one end, (the carb at the other...)

XT500-
It's not a ram air, either, as it's operational at low vehicle speeds and is not dependent on vehicle motion for it's effect.

I understand what you mean about the enormous amount of air volume at high RPM. My present carb is rated at 195 CFM. All CFM ratings are at a hypothetical 100% volumetric efficiency. NO engine is 100% efficient - typical production engines are at about 80 to 85%. So on my car, even at 85% efficiency, that's only about 166 CFM, and that's only at Wide Open Throttle.

Since this car is a city and suburb daily driver, the engine almost never sees WOT, and the intent w/ this directed, pressurized flow is to enhance low to mid-RPM performance (I.E. Tip-in to 3000 RPM). At RPM's above that, the engine produces adequate power (in my opinion). It is low to midrange performance I seek to enhance.

Since the system is open to the atmosphere, high RPM performance will not be negatively affected. Should the system "run out of steam" above a certain RPM, the engine will still be normally aspirated.

In answer to your question of "Where is the (directed, pressurized) air coming from?" it is produced by an efficient engine driven source, a source which induces negligible parasitic HP loss.
By that, I mean, as an example: You are familiar with how turning on your A/C compressor (w/ the idle speed solenoid disconnected) results in an RPM decrease in an idling engine, due to the drag on the engine caused by the compressor.
The prototype system installed on my car causes no such RPM decrease when activated on my engine at idle (and my engine is not equipped w/ an idle speed solenoid). While I am sure there is SOME parasitic HP loss due to the engine-driven source of air, it is far LESS than the loss caused by the A/C compressor, or even the alternator (when in a maximum charging mode).

 

[StrangeRanger]

Without splitting semantic hairs, if you're using engine power to increase intake airflow, it's a supercharger, type and efficiency yet TBD. I have my doubts about whether there's any benefit to be derived with an unsealed intake system. You might be able to raise VE from 0.8 to 0.9 or something on that order simply by providing enough flow to overcome the pumping losses in the stock intake; beyond that, I've really got my doubts.

 

[Anonymous]

Are you trying to re-use the smog pump?

I'd think that all your going to accomplish is introducing heat into the air charge. Also if you tube extends into the snorkel it could represent a restriction at wot. The stock snorkel aren't known for their high-flow capabilitys anyway. The air supply would have to equal engine demand to prevent that. However at that point your not doing any good as your only equalling what you had to begin with. You would need to exceed engine demand.

As you have already built this, why not test it? If engine efficiency noticeably improves the mileage should as well. Try checking your MPG with and without it.

 

[BIGREDRASA]

I remember a similar story in Pop Sci or Mech many rears ago. A stream of compressed air is introduced into the airflow, thereby speeding up the entire volume of the airflow. It will work if you can compress the air sufficiently to create a significant increase in velocity at the nozzle. It could boost power for WOT applications, but there's no free lunch. You're otherwise looking at a perpetual motion machine, or one that has an output greater than its input.

 

[LEROY POLL]

HELLO ROCKO

YOU ARE ON TO SOMETHING HERE, BUT NOT ON A CARB.

THE AIR UNDER PRESSURE IS A FORCE THAT CAN BE USED TO GET MORE POWER TO THE WHEELS. BUT WHEN IT WAS USED IN THE '70S IT WAS TO DRIVE A TURBIN-'O FAN, THAT THEN PUSH AIR INTO THE CARB.

THEY WERE NOT DRIVEN BY THE EXHAUST, BUT BY HIGH PRESSURE AIR. THEY COULD PUMP UP TO 50-60 LBS FOR A FEW SECONDS. THEY WOULDN'T GET HOT, AND THE EXHAUST COULD KEEP SOME KIND OF TUNING. THEY WERE ABLE TO MELT TIRES AT THE LINE. I MEAN TOTALLY MELT THEM DOWN..!!! PICTURES WERE SO UNBELIEVIABLE THAT MOST DIDN'T BELIEVE IT. IT TOOK SOME PEOPLE GIVING OUT JUST HOW IT WORKED BEFORE ANYONE COULD CHANGE PEOPLES MINDS.

AGAIN THE TRACTION WAS THE REAL PROBLEM FOR MOST CARS. ...ARE YOU THINKING ABOUT PUTTING A RECHARGIBLE AIR TANK IN YOUR TRUNK AND A DASH SWITCH ON YOUR DASH...... AAAAHU????? GET RID OF YOUR N-OX' AND GO PURE AIR.

THE BEST ONE WAS A GAS TURBIN AND AN ALL AIR SYSTEM THAT TURNED A DIFFERINTAL AND HAD DRIVERS ON EACH WHEEL. IT NEVER WORKED WELL.... SAFTY WAS A PROBLEM.. WHAT DID IT RUN AGAINEST.....??? THEY NEVER MADE A CLASS FOR THEM IT WAS TOOOOO... MUCH... UP IN THE AIR :roll: :roll: :roll:

JUST ADDING SOME MORE COLOR TO YOUR STRING!

LIVE IN GRACE

LEROY POLL[/b]

 

[Anonymous]

I have no idea what you are talking about LEROY POLL. Have you got any more info or links?

Ps, lay of the CAPS LOCK

 

[82F100SWB]

He's talking about Turbonique stuff, which was quite cool... If I dig around, I have some info and ads... It was in the 60's tho, not the 70's.
Evan

 

[LEROY POLL]

HELLO 65XP

THE ONLY ARTICLE I FOUND WAS NOT EXACTLY WHAT WE SAW AT THE TRACK BUT CAN SHEAD SOME MORE LIGHT ON THE AIR THING.

HOT ROD (PAGE 42) JULY 1967. THIS IS THE IDEA ONLY. THEIR WERE GAS TURBINS TURNING THE AIR TURBINS. THEY USED NO BELT. LATER THEY JUST USED THE GAS TURBINS TO TURN OR DRIVE A WHEEL. FOUR TURBINS. I NEVER SAW IT RUN.

IT ALL STARTED BY USING STARTER MOTOR FOR SUPERCHARGING. IN MY SCHOOL ONE OF MY GROUP GOT A KIRBY VAC. AND ADAPTED IT TO A STARTER MOTOR. IT WAS OKAY AT LOWER SPEEDS BUT DON'T THINK IT DID MUCH ABOVE 3500 RPM. YOU COULD FEEL A DIFFERANCE IN HIGH GEAR AT ABOUT 30 MPH. THIS WAS ON A 1953 FLAT FORD V8 THREE SPD. WE ONLY BEAT OTHER FORDS. OH! (AND ALL THE CHEV'S IN TOWN.) !!! IN THE QTR. MILE HE SAID HE WENT FROM 67 MPH. TO 71 MPH. HE SAID IT ONLY HELPED OFF THE LINE. LATER HE PUT A '50 OLDS MOTOR WITH THE HYDRO IN IT AND IT TURNED 91 MPH.

IF I CAN GET SOME MORE INFO ON THIS I'LL TRY TO GET IT TO YOU.

LIVE IN GRACE

LEROY POLL

WE ONLY USED A 6 VOLT STARTER MOTOR.......NOW I'M WONDERING IF A 12 OR 18 VOLT STARTER MOTOR TODAY WOULD DO MUCH BETTER....??

 

[Anonymous]

Could you please give a little more details as to what your system consists of without giving your idea away? is it some form of belt driven pump? which sucks air in from a high pressure location ( behind front bumper etc ) then speeds up the air and pressurises it with an impellar and forces it into the engine? Basically like a supercharger....but what type of pump are you using...perhaps and aircon compressor?

 

[Anlushac11]

8) FWIW


Someone is selling an "electric sueprcharger" in the Jegs Auto catalog. The device is rated at 450cfm and looks like a small jet turbine. It also IIRC runs about $369(You could almost set up a turbo for that much

There has been some heated debate that any electric driven fan could produce enough air to produce even 1lb of air pressure.


My opinion is that if the device can be tested and proven to provide the cfm of air specified theres still no guarantee what kind of air pressure it could provide. I would think it would give some benefit but testing needs to be done.

 

[Anonymous]

Most of those 'electric' superchargers are just boat bilge vent fans, and some are wired to be overdriven. They won't move squat worth of air for an engine. They are also all over Ebay.

Garret tried (and has) an electric driven turbocharger (simplified). Almost made it to market- but it also requires a good bit of juice, and an expensive controller.

It kinda sounds like the Smog pump idea here- they don't move squat worth of air, either. most are made to dilute the exhaust stream at a 1:20 ratio (meaning 20 times less than the engine is operating on).

 

[Anonymous]

Is it something like this?

 

[Greywolf]

Thermodynamically, you don't really get something for nothing.
A turbocharger, while allowing you to reclaim energy you'd otherwise lose, actually robs you of some horsepower. Ditto for a supercharger. they just give you back far more than they take.
While I believe an electric motor could drive a fan/turbine impellor and produce boost, the amount of power required to drive it would be fairly large. Let's say it's 5 horsepower (about the drag created by an alternator under reasonable load). Have you seen the size of a 5 horsepower electric motor?
Ben
P.S. One of my hobbies is oddball power plants. In 1924 a ship, the M/S Dolius, was built with a diesel/reciprocating steam oddity that used a small steam turbine to drive an air boost pump. It was essentially a steam-driven turbocharger!

 

[LEROY POLL]

HELLO

I'M SORRY BUT WASN'T ABLE TO SIGN ON FOR ABOUT SIX DAYS.

THE AIR DRIVER FOR THIS WAS NOT HOOKED UP TO THE MOTOR. IT WAS A SMALL GAS-TURBINE, ABOUT 12 INCHES IN DIAMETER, THAT WAS THE POWER SOURSE. THIS DROVE AN IMPELLER WHICH DROVE AIR INTO THE CARBS.

THE ONLY TIME I SAW IT RUN WAS ON IT'S THIRD RUN. IT DID NOT START WITH THE TURBINE HOOKING UP, OR MAYBE TURN ON. IT WAS AFTER THE CAR LEFT THE LINE THAT THEY WERE TURNED ON. THE CAR MOVED SO FAST AND THE NOISE WAS SO LOUD THAT EVERYONE JUST ROARED AND IT WAS UNBELIEVIABLE. THIS NOISE WAS OVER THE OPEN PIPES OF THE BLOWN-CHRYSLER GOING BY...(IF YOU HAVE SEEN AND HEARD A DRAGSTER)!!! MY FIRST THOUGHT WAS THAT IT HAD BROKEN AND WAS ON FIRE. THEIR WAS JUST UNCONTROLABLE POWER. EVERYONE HAD BEEN TALKING ABOUT IT BEFORE I SAW IT,.......BUT I WAS NOT READY FOR I SAW.

I WAS TOLD THAT THEIR WAS A HOT ROD ARTICLE ON THE SYSTEM. I WAS NEVER ABLE TO FIND ONE IN ANY MAG. I DID SEE ADVERTIZING ON THEM, AND PICTURES. THE STORY WAS THAT THE TURBINES DRIVE A TURBINE BLADE LIKE A TORQUE CONVERTER WHICH SLOWED DOWN THE AIR DRIVING IMPELLER TO A USEBLE SPEED AND LEVEL. AGAIN I'VE NEVER SEEN AN ARTICLE. IF ANYONE A HAS SEEN ONE ,COULD YOU GIVE US A POST HERE?

ABOUT THIS TIME THERE WAS A TURBINE THAT RAN IN INDY. THE CAR ONLY MADE A WOOOOOSH-ING SOUND. THIS THEORY WAS MADE INTO A SMALL GAS TURBINE THAT WAS THE POWER GIVER. THE BIG DIFFERANCE WAS THE SOUND. THESE GAS-TURBIN'S SOUNDED LIKE A VERY LOUD BLOW-TOURCH,OR JET. .THEY LOOKED LIKE A BLOW- TOURCH WITH FIRE COMING FROM THEM. THEY LOOKED UNSAFE WHEN RUNNING A LOW SPEEDS.

I SAW ONE RUN A OKLA. CITY. A SMALL CHEV-ROT 327 WAS ABLE TO BEAT TWO OF THE FASTEST BLOWN CHRYSLERS THERE. I WAS NOT GIVEN A CHANCE TO RUN AGAIN, BECAUSE OF PORTESTING. I DIDN'T HAVE A PIT PASS SO NEVER SAW IT UP CHOSE.

I SAW ANOTHER ONE A POMONA. STILL ON PIT PASS BUT IT DID NOT RUN,... BUT CAME TO THE LINE TRYING TO FORCE THE MATTER. IT LOOK LIKE IT HAD A GAS- TURBINE ON EACH WHEEL. ALSO HAD A TURBINE I THINK FOR A MOTOR TO DRIVE IT.

I DO BELIEVE THESE WERE OUT-LAWED AND WERE NOT ALLOWED IN TO THE PIT AREA. THE IMPELLERS WOULD TEAR APART, TURBINE WOULD EXPLODE, AND FIRES WERE SOME KIND OF A PROBLEM.

I STILL DON'T KNOW HOW THEY WERE DRIVEN!!! DIRECT?....CHAIN?......GEAR?..... GAS?....RUBBER BAND? I DO KNOW THAT THE IMPELLERS WERE WAY TOO BIG TO TURN THE SPEEDS THEY WERE TURNING.

I HAVE BEEN LOOKING FOR ANY KIND OF WRITE-UP AND HAVE NOT FOUND ONE YET. I HAVE SEEN STILL PICT. OF THEM AT SOME EVENTS.AND TRACKS. BUT NO ARTICLES.

LIVE IN GRACE

LEROY POLL