2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.

air pump into intake-would it work ?

Old Feb 24, 2005 | 06:03 PM
  #26  
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It won't work at all

I am a high schooler and therefore have no knowledge of fluid dynamics. Everything I know comes from some sort of reason. I will now proceed to show you why your air pump will not supercharge your engine any better than an electric blower from a boat.

first, take out your air filter housing.
This will leave you with two pieces.
1. The small air pump hose
2. The afm hooked up to your intake.

Next, compare the size of the opened afm (flap wide open) and the size of the hose going to the air pump. You will notice that at wide open the air pump may be 1/4 of the afms opening. (you could also consider the sizes of 2.5" hose versus a 1/2" hose which would be 5x diff).

From this idea consider this: the pressure from the air pump would need to be able to equalize that volume before even matching the size of the afm.... so to match the size, you would need roughly 4x the pressure. (1 atm==14.7psi x5== 60psi (maybe) to expand to the 2.5" volume)

Now do this, start your car. Consider the suction power from the afm and the air pump tube. You can accelerate your car by pushing the throttle linkage. Feel which one is sucking more.

Also look at the afm and notice how it is moved by suction, wow, that is a lot of suction power.

Based on my fuzzy math and visualizations, the air pump is going to do relatively squat. There is a reason why a supercharger is huge. There is a reason why a turbo charger is relatively larger than an air pump and spinning at hundreds of thousands of rpm.

There is a cap based electric air blower that is effective. I forgot the link, but saw it recently here on the boards, unfortunately those are underdriven electric motors hooked up to high voltage and a larger (turbo sized) pump and cost about $1300.

Last edited by sar; Feb 24, 2005 at 06:07 PM.
Old Feb 24, 2005 | 06:12 PM
  #27  
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ok my hole idea on the vaccum in the intake was wrong, i was thinking of riding in my freinds turbo eclipse, when i let off the throttle there was vaccum because the engine is trying to pull air through the turbo. i still think there is going to be some vaccum in there at wot, it is sucking air so it cant be 0 pressure
Old Feb 24, 2005 | 06:36 PM
  #28  
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BWAHHAHAHAHAHAHA

seen this before

dont worry, i thought of this too, a long time ago.

pat
Old Feb 24, 2005 | 06:47 PM
  #29  
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well this was originally mack123's thread so he gets credit lol. i just still dont see enough data to think it wont give any gains at all. i there was a way to know that the air pump at any rpm doesnt put out as much air as the engine sucks in at that same rpm then this would all be easy to drop. but from how much air i see coming out of my air pump( I just started my car with the hose disconnected) i think it would make it much easier for the engine to breath
EDIT: this is all assuming the airpump is hooked directly to the afm, not simply ran into the side of the intake pipe

Last edited by Mint87RX7; Feb 24, 2005 at 06:53 PM.
Old Feb 24, 2005 | 06:59 PM
  #30  
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dude...a turbo pumps waaaay more air than a airpump, and it has to spin at like 80k rpm to make boost.
Old Feb 24, 2005 | 07:04 PM
  #31  
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i know a turbo puts out insanely more air than the air pump, thats why they make boost. its just that the air pump is free and i think if you hooked it up, it could give you 5 hp. and if it did, it would be fun to try. not trying to compare this to a turbo or sc at all, just trying to figure out what would happen if you did hook it up. if anyone else is curious go disconnect the tube from your acv and rev your car up to 5k and put your hand over the end of the hose
Old Feb 24, 2005 | 07:43 PM
  #32  
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This is one of those guys that just won't listen to reason or explanation, and wishes to invest his time in a meaningless endeavor. Just leave him be...in a week or 2 he'll come back and there will be a small mention somewhere that it seemed to run a bit better on top end but he wasnt sure...of course that'll be those "imaginary" hp gains, the same ones that the guys with hondas get when they put on a set of rims or a cone filter.
Old Feb 24, 2005 | 07:46 PM
  #33  
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ROFLMAO!!!!!!! Hahahahahaha!!!

Hey... Vinyl adds horsepower.


-Justin
Old Feb 24, 2005 | 08:12 PM
  #34  
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well if i ever do try it i will hook up a low pressure guage too so i can see if there is and change at all. I know that this has been brought up like 4 times but they were all just wanting to run the pump into the side of the intake tube to put "extra air" into it that would just blow out the other end. and nobody ever could find any numbers of the output of the airpump( the only thing the fsm shows is the output at idle). so im still wondering how it would work if hooked up correctly
Old Feb 24, 2005 | 08:19 PM
  #35  
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When I posted I wasnt trying to compare the air pump to a super charger. 2.5" pipe versus 1/2" pipe (maybe), you need 5x as much pressure to make up for the volume loss of using the small pipes on the air pump to equal what you were getting otherwise.

YOU WOULD NEED 60PSI from the pump to equal your current intake volume.

Why not just buy several vent blowers from a boat store? They're less than $10, they'll dump cfms from a relatively low volume off of battery power. But these have been proven to do nothing in terms of pressure increasing.

Consider relating this to a turbo charger or superchargers, because that is what this is. Like somebody said, a turbo doesnt really start generating any boost until the compressor is spinning at 80k rpm w/ a 3" outlet on it. Your 1/2" air pump isn't going to give you any power at all going at a measly 8k rpm.

Buy an electric supercharger off of ebay and tell me how well that works.

a 1/2" opening is not going to give your engine nearly enough air to breath (I take that back if you have something that can compress air to 60psi constantly) Have you ever tried breathing under water w/ a straw versus a snorkel, or can you imagine? If you have a fan on the straw it is still going to be harder to get as much air as the snorkel would.

I'm rambling.
Old Feb 24, 2005 | 08:59 PM
  #36  
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it doesnt have to be making 60psi to make up for the volume. it has to move enough air to make up for the volume, I know you dont think it will move enough air but neither of us knows how much air it moves, i dont even know how much cfm the engine pulls at any certain rpm. without those numbers nobody knows how it will work. the amount of psi (small amount, im sure) that is created depends on how much more (if any) cfm the airpump puts out compared to the intake pulls in.
Old Feb 24, 2005 | 09:10 PM
  #37  
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this thread is a broken apex seal waiting to happen...
Old Feb 24, 2005 | 10:29 PM
  #38  
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take a paper towel, see which hose sucks it in the quickest.
Old Feb 24, 2005 | 10:45 PM
  #39  
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Originally Posted by RotaryResurrection


Any engine (natural aspirated), when at WOT, produces 0 vacuum and 0 boost. WOT, unless there is a special circumstance, is the definition of atmospheric. Look.

All around you and your engine is atmospheric, 0 vacuum, 0 boost. Atmosphere is represented as 0 on your boost or vacuum gauge. This is why, when the car is off, the gauge zero's out...atmosphere is the only force acting on it at that time.

So, the engine is running, at idle. During idle, your throttle plates are almost all the way closed...barely cracked enough to let a little air through. Your engine is spinning, and the force of the rotors drawing away from the intake ports is trying to pull air in...but the throttle plates are closed, so not much can enter. Thus, a vacuum is created everywhere between the intake ports and the throttle plates.

Now you open your throttle plates...the engine's vacuum now pulls in more air past the open plates...therefore, the vacuum drops during the time when the air is rushing in.

Open the throttle all the way...unless you have a terribly restrictive intake, there is now almost 0 vacuum in the intake...because there is no BOUNDARY between the atmosphere around, and the engine...the plates are all the way open. There is a very small amount of vacuum present in certain areas of the intake, which is what continues to pull air into the engine.
That is close. Your engine believe it or not is a very large vacuum pump fueled by the combustion. AS those rotors are spinning they are creating vacuum at a certain throughput or CFM The faster the RPMs the higher the CFM So there is a constant vacuum pulling fuel and air into the intake, even with the butterflies wide open. The ports cannot allow enough air/fuel into the rotor housings. Hence, ported and polished allow greater air flow to quinch the thirst.

Not saying that the smog pump would help with at all just wanted to add the only thing I do know......vacuum, vacuum conductance, Vacuum flow, Torr, Microns, mbarr, Hg in inches, name your vacuum language....I 'm fluent.
Old Feb 25, 2005 | 03:07 AM
  #40  
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I do get a kick out of the responses on this site, I could practically write them all ahead of time. You have 2 sides chiming in, and its interesting.

Its obvious if the system worked, it would already be widely used.
I dont have a lot of time to write responses or do searches. Actually the question was written to see peoples experiences about the topic. I keep my cars bone stock.

thanks all
Old Feb 25, 2005 | 08:00 AM
  #41  
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<tongue in cheek>I just have one question to ask...
Will this work well with my Tornado?
Should I aim the output from the air pump at sort of an angle to help get more swirl?

</tongue in cheek>
Anyway, for trivia's sake.. ran across this..
Originally Posted by [url
http://www.yawpower.com/martech.html[/url] ]
For instance, a 13B has a displacement of approximately 80 cubic inches. This means that it can potentially displace, or pump 80 cubic inches of air per revolution. At 6000 rpm, this equates to 480,000 cubic inches, or 277.8 cubic feet per minute.
But, here's an idea.. take an inflatable beach raft with one of those big filler openings.. (the type of opening that is meant for the exhaust of a vacuum cleaner). Now take your bicycle pump and put the hose inside the raft, through the big opening meant for the vacuum cleaner hose. Don't seal up that opening, just leave it clear with the exception of your bicycle pump's hose.

Now start pumping with your bicycle pump.. How full can you get the beach raft? Tired of pumping with the bicycle pump? Take a little emergency car air compressor, and repeat the experiment. Tired of waiting for that? Take your shop air system and try it.. think about the power required to generate what results you get and see if you feel it is efficient in terms of those results.

Anyway, my point is that all you can really hope to do is try to offset the head losses due to flow restrictions in the intake tract, but you have designed your intake tract to be as unrestricted as you can manage, and the machine you are trying to use is not an efficient mechanism to pump air like that...

Generally, the automotive engineers aren't completely stupid... You can make "improvements" over what was done on a car by changing what compromises you are willing to accept (fuel economy, expense, reliability, comfort, noise, etc.), but it's very, very rare that you can really find a free lunch without a major shift in technology or scientific understanding.
Old Feb 25, 2005 | 08:07 AM
  #42  
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here is the bottom line: you will get more power gains from taking the airpump off then you will from plumbing it into the intake. remember that any power used has to come from the crank, so if you pump 5hp worth of air, it will drain 5 hp. this is only a good exaqmple for small cfm, since with efficient, large cfm pumps like supers and turbos its obviously not true. however, with a real inefficient small pump setup like youre talking about...i dont see it making any more than it draws.

pat

ps now that i think about it....hey man, go for it. try it. you will be much more satisfied with the results of actually trying it then you will from what we tell you. it will only take 15 minutes anyway.

in fact, ive got 4 or 5 extra airpumps you can have if you want em...you could try stacking em all up...

Last edited by patman; Feb 25, 2005 at 08:12 AM.
Old Feb 25, 2005 | 08:12 AM
  #43  
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well machine a pulley for the airpump that is like 1inch diameter instead of the beastly 6 inch. Granted it would still not work, but i would pump at least 6 times as much air. (or is would it be a raised to the 6th kind of deal?) anywho, the thing wont do it. the velocity, which wont match a turbo's capacbility is not everything. The mass of the air will not measure up. You might speed the air up a bit, but not manage to compress it.
Old Feb 25, 2005 | 08:38 AM
  #44  
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I don't think your getting the point, unless all the air that enters the engine came in through the airpump aany additonal positive pressure it creates will just flow out the intake. The airpump produces such a low cfm that even if it did work without all the air entering the engine going through it it would still take just as much power to run as it could possibly produce. the only way to make power with that air pump is to take it off the car. I would thing that even those ebay electric superchargers that do nothing would be better than this idea
Old Feb 25, 2005 | 08:45 AM
  #45  
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if you connect it to the air pump, sealing it to the air pump, you will see a change in the vacuum @ WOT.

THE VACUUM WILL INCREASE, your air pump is going to just be a stupid convoluted path for your engine to draw air through, it won't keep up with the motor let alone create boost!

try it, you're not going to pop anything, your car is going to be slow it will be like having the throttle stuck at 10% open when you're flooring it.
Old Feb 25, 2005 | 09:01 AM
  #46  
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We've been through this before. Won't work.

Search "air pump supercharger" if you want to know.

Thread closed. I don't have the energy or time to clean up all the UTTER CRAP posted here.
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