Technology
Carburetors that Never Flood? Is Fuel Injection Even Better?
In this episode of the Engine Noise Podcast, hosts Jeremy Nutt and Matt Lantaigne dive into the world of carburetors and fuel injection. They discuss the evolution of carburetors, including the unique...
Carburetors that Never Flood? Is Fuel Injection Even Better?
Technology •
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Interactive Transcript
Speaker A
Welcome to the Engine Noise Podcast, brought to you by our awesome sponsor, 1aauto.com, a podcast for do it yourselfers like me, who know exactly how to never finish a car restoration. I am your car guy and favorite podcast host, Jeremy Nutt.
Speaker B
And I'm Matt Lantaigne. And I hear you're there, Jeremy. Sometimes things just. You just can't finish things.
Speaker A
Yeah, it just takes a long time.
Speaker B
You know, Things, things come up, you know?
Speaker A
Yes. Sometimes you're like 15 years old and you buy a project car and then pretty soon you're like 39 and the project car's not done.
Speaker B
Yep.
Speaker A
So what are you gonna do?
Speaker B
Time goes by pretty quick.
Speaker A
Yeah, I mean, you know, it's just hard to finish things in 24 years. You know, you gotta, you get a couple of things and, you know, you gotta eat dinner sometimes you gotta go to school.
Speaker B
Yeah, no, it's totally understandable. You don't have to make excuses, Jeremy.
Speaker A
It's fine. All right, well, all right, well, today I have some cool topics.
Speaker B
Hit me.
Speaker A
All right, so the show lineup is. All right, I'll tell you, Matt. I'm just gonna tell you I'm ready.
Speaker B
I've been waiting with bated breath.
Speaker A
Alright, today we have an important show about something that I hate and something that I love. Oh, that's right. We're talking about carburetors.
Speaker B
Ooh.
Speaker A
We're talking about fuel injection. Aha. Okay, you can guess, you can guess which one I hate and which one I love.
Speaker B
Matt, I, I am gonna say carburetors.
Speaker A
Yeah, I hate them. Yes.
Speaker B
Yeah, I don't blame you.
Speaker A
Now the listeners might be saying, Jeremy, you have already told us about carburetors and how they should be left in the 1800s and that they should all be locked in an abandoned salt mine and yeah, you're right, I don't like carburetors. But we have not discussed the evolution of carburetors and the one carburetor that will never flood your engine. Oh, interesting fun fact there for you. And we have also never discussed all of the totally rad types of fuel injection that exist. I think at some point we might have talked about like some direct injection or something. And maybe we talked about a little injector stuff here and there, but we never really covered the batch fire injection, the throttle body injection, the multi port sequential fuel injection, that kind of stuff.
Speaker B
Wow.
Speaker A
So we're about to cover all these in one absolutely beautiful episode of Engine Noise Podcast.
Speaker B
I love it, Jeremy.
Speaker A
Yeah. So let's get Started.
Speaker B
Let's go.
Speaker A
Engine Noise Podcast is brought to you by 1aauto.com quality auto parts that ship quickly and come with thousands of free online videos that walk you through your installs. All right, Matt, the year is 1738. And you remember that year, right? 1738. Yeah.
Speaker B
We're going way back.
Speaker A
Yeah. How old were you then?
Speaker B
I think I was, like, two.
Speaker A
Oh, wow.
Speaker B
I was still really bad at math.
Speaker A
Yeah. Yep. Well, in 1738, I'm pretty sure, like, around then, it was one of those things where if you really liked rocks in 1738, you could just start calling yourself a geologist because you just really liked rocks.
Speaker B
Why can't it be like that now?
Speaker A
I don't know. And then, like, if you really like science, like, then you just start calling yourself a scientist. Like, I don't know if you actually need qualifications to. To just become things in the 1700s. I don't know, but I'm pretty sure.
Speaker B
Is this where, like, the last names were established, where you just did that thing? So that was your last name, Like. Yeah, Shoemaker. If you made.
Speaker A
Yeah, I think that was pretty much it. So in 1738, it's. It's a weird time. You know, the world is going through some things, and there's this guy named Daniel Bernoulli, and he was a Swiss mathematician. Now, you may remember that I just mentioned that I think pretty much anybody can call himself a mathematician in the 1700s. And. And that may or may not be the case. I don't know.
Speaker B
Are you trying to downplay Bernoulli?
Speaker A
I'm not. I'm not downplaying him because he did some great stuff, but I'm just saying, you know, I don't know, like, in the set in 1738, could I call myself a mathematician because I really like doing multiplication? I don't know.
Speaker B
Right.
Speaker A
So Daniel Bernoulli allegedly was a Swift. A Swiss mathematician. Now, he was probably pretty legit because he wrote a book in 1738 called Hydrodynamica, which is a dope name for a book.
Speaker B
Wow, that sounds like a rock band or something.
Speaker A
I know. It pretty much could be. And if we start a band. Matt, that's not a bad name choice right there. Yeah, Hydrodynamica is a great name. So in this book that he wrote, he talked all about fluid dynamics, which, yes, I think you'd have to be probably pretty smart to write about. So I'm giving Bernoulli his credit. So with the fluid dynamics came Bernoulli's principle, which, lucky. I mean, yeah. Pretty. Pretty cool. So he came up with this principle that said an increase in speed of fluid occurs simultaneously with a decrease in pressure or decrease in the fluid's potential energy. And you know what? I read that, and I was like, I don't know what that means.
Speaker B
Yeah.
Speaker A
So then I started digging into it a little bit, and it turns out I'm gonna explain this in Jeremy terminology.
Speaker B
Okay.
Speaker A
Okay. What this means.
Speaker B
Yeah.
Speaker A
Okay, so imagine you have a cup of water, and you take this cup of water and you drop a straw in it.
Speaker B
Yeah.
Speaker A
And then you send a whole bunch of air over the top of the straw.
Speaker B
Mm.
Speaker A
So you're, like, blowing over it, going.
Speaker B
Yeah.
Speaker A
Over the straw.
Speaker B
Yeah.
Speaker A
When you do that, the straw will draw the water up from the glass through the straw, and it will spray out the end of the. Of the straw.
Speaker B
Is that true?
Speaker A
It's real. Yeah. This is, like, a thing.
Speaker B
How come I've never done this before?
Speaker A
It's a science project that you should totally do. And the way if you really want to do this in your house, the way you do it is you get the cup of water, you put a straw in it, and then you get another straw, and you use that straw, the second straw, to put it in your mouth, and you blow air, like, right at the top of the straw that's in the glass.
Speaker B
Yeah. And.
Speaker A
And when you do that, all kinds of water will basically come out of the cup through the straw, and spray all over your table.
Speaker B
Well, I wanna do this right now.
Speaker A
I know, right?
Speaker B
Sheesh.
Speaker A
So this is basically Bernoulli's principle. This is basically him saying, when you put a bunch of air over something, it's going to cause a low pressure area, which will then draw fluid up the straw and spray it out the top of the straw. Boom. Bernoulli's principle, in Jeremy terms.
Speaker B
Crazy.
Speaker A
Yeah. It's really cool. And that is how carburetors work. So a carburetor is basically this cup of water filled with fuel instead of water.
Speaker B
Yeah.
Speaker A
And the straw is the venturi that is in the carburetor. It's just basically a tube. Oh, well, it's just basically a tube. And it's like.
Speaker B
It's.
Speaker A
Yeah, it's pretty much. Well, it's in the carburetor, there's like a. There's what's called a carburetor float bowl.
Speaker B
I know that.
Speaker A
Which is basically just a cup.
Speaker B
My lawnmower's got one of them.
Speaker A
Exactly. Yeah. So it's got the float bowl now in that bowl is a bunch of gas, and coming out of that bowl is a tube, which is called a venturi. And that tube has a very small orifice in it. Very small. Like, it's a very small tube.
Speaker B
Yeah.
Speaker A
And as air passes over the end of that tube, it draws the fuel out of the tube and into the engine. Like through the carburetor. Yeah, it's. It's pretty kind. It's kind of cool.
Speaker B
Yeah.
Speaker A
So that is how a carburetor works. It works because of Bernoulli's principle. And you're probably saying, well, that's all cool, but who actually invented the carburetor? And I'm about to tell you, Matt.
Speaker B
That's exactly what I'm thinking.
Speaker A
Right. There's this guy named Samuel morey, and in 1826, he invented the carburetor according to the Internet.
Speaker B
Hmm.
Speaker A
But his method of carburetion was a little bit different than what we just talked about. His was basically, you have this cup of fuel, and you just pass a bunch of air over the top of it, and the air going over the fuel just kind of takes the fuel fumes and it drops it into the engine, and the engine runs. And that's all well and good, but it's not as good as it could be. Using the straw into the fuel float bowl is a much better design. And that is where our friends Carl Benz, who you may know from Mercedes Benz.
Speaker B
Ah.
Speaker A
Wilhelm Maybach from the Maybach Car company, And Gottlieb Daimler from Daimler Chrysler.
Speaker B
These are tough names.
Speaker A
Yeah, I know, but all these dudes were pretty much right at the forefront of carburetion in the late 1800s. They were all, like, coming up with new carburetor designs, and they're basically the ones who took Sam Morey's design and kind of turned it into what the modern carburetor is now, where you have a venturi going into a float bowl, and you're actually atomizing the fuel, and it's going down into the engine. So. So pretty cool question for you. What.
Speaker B
What produced the air or, like, pushed the fuel into the engine from the venturi?
Speaker A
Yes. It's a negative pressure inside the engine. So when the piston goes down, it causes a negative pressure inside the engine because the valve is, like, closed at that point, and the piston's going down, and then the val. And then the valve starts to open up as the piston's going down, and it draws in a whole bunch of air and fuel mixture through the carburetor.
Speaker B
Ah, I see. Now that makes sense that that is Bernoulli's principle.
Speaker A
Exactly. And then because there's so much air rushing in, it pulls in the fuel with it, going past that little venturi. And you get the right mixture, you do a little tuning on the carburetor to make sure you get the right air and fuel mixture, which you never do.
Speaker B
You never do.
Speaker A
Which you never do. And then on the other side of the carburetor, there's a throttle plate, and that throttle plate goes. Gives you more or less air going through the carburetor. And then there's also another plate in there called a choke. And what the choke does is the choke basically blocks off all the air. So that means the piston comes down, it draws in, like, way more fuel than air. And that's what a choke does on the engine. It basically floods it with fuel so that it can start up really easy. And then as soon as the engine's running, then you turn off the choke, and it gets the normal air fuel ratio, and it's a much happier running engine.
Speaker B
Okay.
Speaker A
Yeah. Pretty neat, right?
Speaker B
Most early cars had carburetors, right?
Speaker A
Yeah, cars pretty much had carburetors from the late 1800s, right up until, like, the 19, early 90s. Yeah. But these carburetors came in three different styles, generally. And in the early early days of automotive design, there were updraft carburetors. And an updraft carburetor means the air came up from the bottom and through and out the top of the carburetor. And you would find these usually on cars between the late 1800s, probably the early 1920s. And you'd also find these on tractors. So if you ever go see an old tractor that's like, you know, we'll say 19, 30 and before, it probably has an updraft carburetor on it. So I know around Massachusetts, every ice cream stand seems to have an old tractor in front of it. So the next time you're at an ice cream stand and you see an old tractor sitting nearby, go check it out, because it's probably got an updraft carburetor on it.
Speaker B
There you go.
Speaker A
Yeah. And the cool thing about updraft carburetors is you pretty much can't flood an engine with an updraft carburetor, because when you flood an engine, it basically means that all of this fuel is kind of sitting in the intake manifold, and it's just too much fuel, and it essentially, like, wets all the Spark plugs. And the spark plugs don't want to fire, and it just floods the whole thing out with fuel and not enough air. But if you have an updraft carburetor, the fuel can't pool in the intake manifold because the fuel would just drip out the bottom of the carburetor because that's. It's an updraft. Like.
Speaker B
Yeah.
Speaker A
All of the air goes up from the bottom, so therefore there is no place for the fuel to pool and cause a flooded intake manifold. So that is a fun fact about updraft carburetors. But the problem with updraft carburetors is. Oh, actually, let me tell you one more fun fact about updrafts. Updrafts are also cool because you can have them really low on the engine and you can gravity feed fuel to the carburetor. So you don't even necessarily need a fuel pump because you can have the carburetor so low that it can be lower than the fuel tank and you can skip the fuel pump altogether and just run, you know, straight fuel from the tank to the carburetor and up to the engine. Yeah. Pretty cool, right?
Speaker B
Yeah.
Speaker A
The downside though of updrafts was that they were so low on the engine and it made them. It made the intake manifold and the carburetor take up a lot of valuable space on the side of the engine. So what ended up happening was a lot of engines kind of swapped over to be downdraft carburetors. And a downdraft carburetor is probably what most people think of carburetors today. Like a modern carburetor, it has air that goes down from the top, goes through the carburetor, and the air fuel mixture goes out the bottom and it goes into the intake manifold. So if you pop the hood of your, let's say, 1970 Chevelle.
Speaker B
Yeah.
Speaker A
You got your big block 454 in there. You got your four speed Muncie out back. You got your 411 posi gears. You got your front disc brakes, got your cowl induction hood. Sweet. And under that super cool air cleaner is a four barrel carburetor. And that is a downdraft carburetor. So basically the air comes in the top through the air filter, through the carb into the intake manifold. So that is what a downdraft is. Now a downdraft is great for like a V8 because the carburetor fits nice and snuggly. In between the two cylinder heads. It's nice and compact and there's less parts than if you were to have multiple small carburetors or even a side draft carburetor. Now you're probably like, what the heck is a side draft carburetor? Am I right?
Speaker B
Well, I thought that was the original carburetor.
Speaker A
No, no, updraft was the original.
Speaker B
Oh, okay.
Speaker A
Yeah. So there's updrafts, there's downdrafts, and there's side drafts.
Speaker B
Okay. I'm just. I pictured automatically the side draft because of the straw over the other straw technique.
Speaker A
Ah, right. Yes, Gotcha.
Speaker B
Okay, side drafts, go ahead.
Speaker A
So the side draft carburetor is what you would find on tons of different motorcycles. Motorcycles are like. I mean, any carburetor on a motorcycle is probably a side draft motor.
Speaker B
Side draft city. Side draft city, man.
Speaker A
It's what they do. You'll also find them on some really cool European cars. Some like maybe some older Jaguars, maybe some old Triumphs, maybe an MG or two, that sort of thing. There was a few American cars that came with side drafts as well, but they're just not as. They're not very common. Some people will use them on performance scenarios. So maybe you have like a. Maybe you have a Honda Civic and you want to do. And you want to do a simple carburetor setup for it. Now why you'd want to do this, I don't know, but you got a four cylinder engine, it's an inline engine, and you could put individual side draft carburetors on each cylinder. And it's really cool to do that because then you can tune each cylinder precisely with its own carburetor.
Speaker B
Oh.
Speaker A
So if you find cylinder three, decide it wants to run a little bit richer than cylinder two, you can tune the carburetor perfectly for that specific cylinder on the engine.
Speaker B
It's like as close to digital as possible. That's still analog, right?
Speaker A
Yeah, it's pretty cool. So like in the updraft world, you'd usually have one updraft carburetor for the whole engine.
Speaker B
Yeah.
Speaker A
And in the downdraft world, most likely you're going to have one carburetor. There is some exceptions where you'd want to have multiple, like single barrel carburetors or a couple dual barrel. You have a tri power setup or something like that. But with side drafts, you almost always have multiple side draft carburetors and you have one for each cylinder. And it's. They sound really Cool when you rev up the engine. And they are really cool for tuning. The downside of them is that they take up more space, they require more expertise to tune them because now you have four carburetors to tune or six carburetors or eight carburetors to tune.
Speaker B
Right.
Speaker A
And it's, you know, you have to know what the heck you're doing to tune them all properly. And yeah, there's just more pieces and parts. So unfortunately, the early 90s showed up and was like, hey, dudes, carburetors are out, fuel injection is in. And then people put on their roller skates and then that was the end of the carburetors.
Speaker B
Oh, boy.
Speaker A
So, sheesh, Sorry, carburetors. I know. And with that, I think we should do a little ad and then we'll talk about some fuel injections.
Speaker B
I think that's a great idea, Jeremy.
Speaker A
Why, thank you. 1A Auto now carries TRQ brand auto parts, which, as you know, is the brand to buy. TRQ stands for trusted reliable quality. And I know this because, because I literally have TRQ brakes on my car right now, Matt.
Speaker B
Oh, did you get those super nice epoxy coated rotors that, like, don't rust like the other brands?
Speaker A
Of course I did. You know, I gotta keep my Subaru looking fresh now. Not only that, Matt, but they fit perfectly. If you need brakes, definitely check out the TRQ aftermarket auto parts. You can shop them at 1aauto.com today and if the listeners go to 1aauto.com enp for engine noise podcast, that will let 1A Auto know that you heard that from us. All right, Matt, are you ready to talk about fuel injection?
Speaker B
I sure am.
Speaker A
Alright. So way, way long ago in the 1920s.
Speaker B
The roaring twenties.
Speaker A
The roaring twenties, there was this guy who was a Swedish engineer and his name was Jonas Hesselman. And according to the Internet, he's the guy who pretty much came up with fuel injection.
Speaker B
Well, it's on the Internet, Jeremy.
Speaker A
Right.
Speaker B
Gotta be true.
Speaker A
I know, I know it. So he gets the credit for inventing fuel injection. And legend has it that he did this for plane reasons. He basically wanted guys in planes pilots. Yeah, to be able to fly upside down and backwards and upside and like right side up and like down and up and all these different directions. And carburetors were like, we don't really like doing that.
Speaker B
Oh. Oh, that's a good point. Wow. Yeah, I never thought of that.
Speaker A
Yeah. So like you flip a carburetor upside down and now your float bowls pouring out all your fuel.
Speaker B
Yeah. Well, I didn't know that. I never flipped my tractor.
Speaker A
Yeah, I know.
Speaker B
Luckily, I haven't done that yet.
Speaker A
Luckily. Yeah. So Jonas Hesselman was like, you know what? We gotta make some fuel injection for these planes so we can do some cool moves up in the air.
Speaker B
Cool. I find that to be a valid reason.
Speaker A
Yeah, totally. So he comes up with this kind of crude fuel injection system, which is like mechanical fuel injection. Mechanical fuel injection is a very simple way of injecting fuel into an engine without having bowls of fuel.
Speaker B
There's basically, like, some guy with a crank on the inside of the cockpit.
Speaker A
It's. Yes, it's exactly that, except without a guy. Instead, you have a belt. So you have, like, a belt that runs a pump and the pump. Yeah, exactly. And then the pumpkin just has this, like, little rotating thing in it that pumps fuel at different times to different cylinders. And then you control how much throttle you give it by opening and closing the air that goes into the cylinders. So it's a very simple setup. It is really good for giving an engine full throttle or a very little amount of throttle, everything in between. It's difficult because when you rev up an engine, the whole revving, like, RPM range needs different amounts of fuel. And it's not always, like, a linear thing. It's not always, like, okay, at like, 10 RPMs, you give this much fuel, and 20 RPMs, you have double the amount of fuel.
Speaker B
Right.
Speaker A
It just doesn't work that way. So because engines, you know, have different fuel needs at different RPMs, mechanical fuel injection can be a little bit difficult to tune because it wants to be a very linear thing. And that's not how engines necessarily are. So they're great for, like, drag racing because it's just like, full throttle.
Speaker B
Yep.
Speaker A
Straight. Give it all the fuel you can. And it's probably great for planes because it's pretty much like, give me all the fuel. But on, like, a daily driver where you're driving to work and back, you probably don't want mechanical fuel injection because it's not the most best way to deliver fuel through the whole RPM range.
Speaker B
Right. So. So what do you. What did they do?
Speaker A
So naturally, fuel injection evolved. So they started, basically, electronics got involved, and people came up with a bunch of different types of fuel injection. It was. It was an evolution process from there. So that was in the 1920s, and it was. And it was intended for planes. Then, you know, some people start putting it on motorcycles and cars and dirt bikes and, like, all kinds of weird engine Scenarios. And it evolves until probably the 1980s is about when fuel injection really kind of comes up to its, its prime.
Speaker B
I'm actually surprised it took that long.
Speaker A
I know, right? Yeah, it took. It took quite a while for it to catch on. And I think it was a. I think it was a technological reason because the technology just didn't exist yet to, to be able to control fuel injector injectors as fast as they needed to be controlled.
Speaker B
Gotcha.
Speaker A
That's my theory, at least. I don't know.
Speaker B
Well, I guess that combined with like the carburetor worked for so long, so.
Speaker A
Yeah, exactly. Yep. So the 1980s come along and things are pretty cool.
Speaker B
Oh yeah.
Speaker A
And you know, the music's pretty great. So obviously. And the car manufacturers are now realizing that they can take off the carburetor and put a throttle body fuel injection setup pretty much in the exact same spot that the carburetor was. So they need to do very minimal changes to the rest of the engine. And they can just plop this throttle body fuel injection in its place and everything's cool. And now they have fuel injection instead of carburetion. And they have a lot more control over the amount of fuel that the.
Speaker B
Engine is getting, which is totally rad.
Speaker A
Which is totally rad. So they do that. And throttle body injection is really neat because like I said, it goes right in the place of a carburetor. And it's got like either one or two injectors usually. Sometimes you have three, sometimes you have a couple more. But generally it's like one or two injectors. So it's very basic. And there's just like a throttle plate that opens and closes and it has a throttle position sensor on the side so it knows where the throttle plate is. So as the throttle plate moves open, it gives a little bit more fuel based on the computer. And it's just a very basic design that just works. And that then evolved into multi port fuel injection. So multi port fuel injection is like when you have an injector on every cylinder of the engine. So if you have an eight cylinder, you'll have eight injectors. And this was actually really cool in its own way because if you're putting an injector like right at the top of the intake valve for every cylinder now you have a lot more flexibility with your intake manifold design. And it's, it's sort of like the same, the same thing I was talking about with the side draft carburetors, where if you have the side draft carburetors, you can do like anything you want with the intake manifold because they're so simple. It's just a pipe that goes from the carburetor to the cylinder head. And with the multiple or multi port fuel injection, you have the injectors right next to the intake valves in the intake manifold. And then you have all this other space to do whatever you want with an intake manifold. So in the case of like a car that has a interesting shaped hood or like a minivan, for example, where you need to have the intake manifold like tucked under the cowl or something like that.
Speaker B
Yeah.
Speaker A
And you need to put the intake manifold like down behind the engine or something like that. You can do that now because you don't have to have this throttle body injector setup that they previously had sitting right on the top of the engine. Now you can put the throttle body wherever you want it under the hood and you can have an intake manifold that's any funny shape that you want. And it doesn't really matter because the, the fuel is still going to get to the cylinders because it's right next to the intake valves and the throttle body, the throttle body doesn't really care where it is as long as it's attached to the intake manifold. So it just gave the engineers a lot more freedom to design different shaped intake manifolds for better engine efficiency and for better usage under the hood of some of these new, newly designed cars.
Speaker B
Right now, if it was me and I had a minivan and the thing didn't fit, I would just use the throttle body. I just cut the hood and have a super sick intake on top of the hood.
Speaker A
Exactly. I mean, I would do, I would definitely do the same thing. And along with the, the individual injectors on every cylinder, this also meant that the engineers that were actually making the engines run, they had more control over each cylinder. So they could tune each cylinder perfectly just like you would with a side draft carburetor. It was, it was really specific tuning for every single cylinder, which is really, really cool to have. So then there's two different types of injection that you can have. In a multi port fuel injection setup. You can have what's called batch fire injection, which is basically you spray all the injectors at once and it doesn't really matter where the piston or what the piston is doing.
Speaker B
Okay.
Speaker A
So like, so it just says, okay, every rotation of the engine, I spray the fuel once. Yeah. And all the fuel sprays at the same time. And all the cylinders get their fuel, and all is cool. The other option is sequential fuel injection, which you see on a lot of cars, and that actually times the injector sprays, like when the piston is in the right position. Right. So, like, as the piston goes down and it wants the fuel, then the injector opens up when the intake valve spray or intake valve opens, and it sprays the fuel in the cylinder, and then the intake valve closes and the piston starts to come back up. Yeah. And you have it all timed perfectly for every single cylinder. And again, this makes the engine more efficient, makes more power, less emissions.
Speaker B
Yes.
Speaker A
Just all the good things.
Speaker B
It seems a little complicated to just have it spray that one time because, like, don't the pistons move at different times on every cylinder?
Speaker A
Yes, very much so.
Speaker B
Would it just, like, kind of, like, burn a lot of fuel in one cylinder and then a little less in another at the same time, and then, like, burn leftovers as it, like, went?
Speaker A
I think it probably burned the fuel equally across all the cylinders. But what could happen is you'd end up pooling fuel behind the intake valve when the intake valve is closed. So the intake valve is closed, and then the injector sprays, and the injector or the fuel coming out of the injector just sits there waiting.
Speaker B
Right.
Speaker A
And for the intake valve to open. And then as soon as the intake valve opens, it kind of, like, pours into the cylinder rather than being misted in, like, in an atomized way.
Speaker B
Yeah. So I would imagine that wouldn't be very good for, like, fuel economy and stuff.
Speaker A
Yeah, I mean, it still works. It's probably still better than a carburetor, I would say.
Speaker B
Wow. Okay.
Speaker A
But it's not as good as the sequential fuel injection.
Speaker B
Right.
Speaker A
And then lastly, we have direct injection, which is the newest, coolest type of injection.
Speaker B
The new hotness.
Speaker A
It is. And this is what you'll find in a lot of new cars, new Corvettes, a lot of new. Pretty much most new cars that are advertising really great gas mileage have some sort of new direct injection. And direct injection is cool because the injectors actually inject fuel directly into the cylinder itself. They don't go. They don't sit behind the valve anymore. It is. It is spraying fuel directly at the piston. So that is really cool because you can spray fuel at a much higher pressure, which means better fuel atomization. And better fuel atomization can lead to more efficient burning, which is more efficient usage of fuel, which is better gas mileage. And the other cool thing about direct injection is because they have such precise control over the fuel that is going into the cylinder. Now they can actually do multiple sprays of the injector for one stroke of the piston. Oh, so you'll have a piston coming up and it might spray just a little bit to get the fire going inside that cylinder and then it'll spray a lot more when the piston is like just about to like reach the top of the cylinder. And that could potentially make a whole lot more power and more efficient burn because there's already some fire in the cylinder. And now you spray more fuel on it and you get more fire and more pressure and. And you push the piston back down and all is well.
Speaker B
Sounds complicated.
Speaker A
It is really complicated. And it all happens in like millionths of a second or something like that.
Speaker B
Exactly.
Speaker A
So, yeah, although, like, to a human eye, it just looks like the direct injection is just spraying constantly. It's actually doing multiple sprays over the course of a few milliseconds or millionths of a second. I don't even know what it is, but. But it's very quick. And yeah, it allows for really precise tuning of the engine. And yeah, you can get a lot more efficient usage out of it. So, yeah, that is direct injection for you. And that's all I got for injection, Matt. That's it.
Speaker B
Well, it sounds super complicated, but pretty cool. And it makes sense as to why it took this long. I'm sure it's just gonna get better and better and better anyways.
Speaker A
Absolutely. Until we just switch over to electric cars and then we just don't have injection anything.
Speaker B
Yeah, exactly. We perfect it and then we just kill it, you know?
Speaker A
Right. It's like the Pontiac Fiero. You get it absolutely perfect in 1988. You have your Lotus suspension, you got your V6 engine, your five speed transmission, you got your sunroof and then you're like, nah, we're done with it.
Speaker B
Yeah, well, some things, you know, just gotta come to an end.
Speaker A
All right, well, should we wrap this one up, Matt?
Speaker B
Let's do it.
Speaker A
All right. Thanks for listening to this week's episode of Engine Noise, a podcast brought to you by Our amazing sponsor, 1aauto.com Quality auto parts that ship free and have thousands of how to videos to walk you through your installs.
Speaker B
Thank you to our awesome editor, Torren Johnson, and to all of our listeners. Be sure to subscribe so that you be notified every time one of our episodes drops. And remember to, like, follow and share our show on Facebook, Instagram and Twitter. Thanks again for listening and until next time, continue to diy.
Topics Covered
Engine Noise Podcast
carburetors
fuel injection
DIY car restoration
automotive design
Bernoulli's principle
updraft carburetors
downdraft carburetors
carburetor float bowl
multi port sequential fuel injection
throttle body injection
project car
car restoration tips
automotive history
car maintenance