How Turbocharger Wastegates Work - Internal Vs External

[@jwardTLS]

Simple but informative. I am in the process of upgrading the turbo on my car right now and just swapped over my wastegate last night to the new turbo so the timing on this is fortuitous because everything you are illustrating is what I'm seeing up close and personal right now. I love this channel. The enthusiast car community desperately needs real, hard technical information like this that explains how things in cars work. The amount of ignorance you find from armchair experts is astonishing. You're filling a very real need with your videos.

[@JapanScott1]

You should include some waste gate sounds for those who aren't aware of the sound.

[@DriftNick]

+Scott Koenig Wastegates don't really make a sound, it's pretty much just another exhaust.

[@JapanScott1]

Yes, it is just exhaust.... but wastegates/blow-off valves have a very unique sound. A rush of air, a tweet, a woosh.....

[@DriftNick]

Scott Koenig Wastegate's and blow off valves are two different things, I would think after a video explaining how wastegates work people would understand that.

[@JapanScott1]

+DriftNick after some research, I stand corrected. 😬

[@Vidarx2]

@@JapanScott1 No u dont

[@Someguy7488]

dude I use you as like a free college 101 course your videos are amazing

[@wilson4079]

Hello fellow N54 owners

[@ZORGONICAL]

Still got it?

[@wilson4079]

@@ZORGONICAL I'm never going to sell this car at this point lmao

[@crankbaitincowboy9053]

7.3 powerstroke actually 😂

[@13hzpodcast88]

N55B welcome?😅

[@hoodiedrifts3994]

Howdy

[@BoostedFilms]

Internal wastegates can also often lead to boost creep if the turbo turbo size is increased or the boost is raised with a boost controller. External gates are almost always the best option for mild to heavily modified cars.

[@HntrSvrsn]

Hey I'd love to see a video on sizing turbochargers, A/R ratio and all the math that I'm sure goes into it.

[@tony5haw]

Yeah Id second that. I would love to know how to size a turbo for specific boost on different sized engines

[@timothyjamieson1282]

Yup I would love to see that too please. Can you include diesel calculations too?

[@farerse]

Hi, I have 2 requests for videos that you could make.. :) timing chain vs timing belt and distributor ignition wires vs coil on plug.. I would like to know the pros and cons ,thanks

[@DoublePortalInc]

for the first one, theyre pretty much the same except a chain is way noisier, and last longer since a belt can snap

[@JBMSTRIKER71]

farerse Okay first of which the elastic limit on a timing belt is a lot better in high rpm. A chain is more durable and will stretch out of ignition timing when it gets worn out. a timing belt can snap and your valves can hit the pistons. Distributors are mechanical and spin in a circle like a eight round revolver firing on each piston and is usually vaccum advancing itself as the rpm rises for a better ignition timing in a higher rpm. A coil pack is computer and electronically fires for ignition timing and the ecm advances itself electronically. Distributor is mechanical old school and better simplicity than the coil pack. Price wise all depends a coil pack on some models is one part and is usually cheaper than a distributor and ignition coil. some models have multiple coil packs.

[@TTime685]

JBMSTRIKER71 Coil packs are definitely better than a distributor.. No moving parts and it's controllable through the ECU

[@mykejohnson582]

@@TTime685 IMO the coil packs last longer, but not necessarily better, the distributor can handle more fire, deliver a quicker spark in some cases provided, you have the right kind of plugs and wires, but they don't last as long as a coil pack, now seems like all manufacturers are using coil packs now a days as that's the whole purpose behind the platinum spark plug as you can go 100,000 miles straight out the factory doors before a single change, but if you want rapid fire the distributor is the way to go.

[@waydigga1982]

This brings me back to my dodge srt4 days! Ppl would either replace the wastegate actuator with a stiffer one (to hold boost better) or put a preload on the spring....Some stock wg actuators allow you to adjust preload of the spring...This is essentially compressing the spring in it's "resting/closed state"... Making it tighter/stronger (preventing the wg from opening as easily)... Which in turn allows the turbo to make more boost or hold peak boost longer. Interesting stuff for sure.

[@sinaniii]

this guys is awesome, like fo real. always helps me out when there is stupid videos out there that doesnt even explain what i want to know. THEN i go to this channel and after 5 minutes i know EXACTLY what i need to know, sick. thx alot man

[@maxpayne044]

Also having an external wastegate venting to the atmosphere, the sound produced when it opens sound awesome. Internal wastegates doesn't give you that screaming sound.

[@jxke9299]

5 years later... you can now buy external dumped down pipes lol

[@akubuosamuel4194]

That's the best explanation about wastegate I have heard. God bless you Sir. I'm an engineering student.

[@tomroberts9591]

Most kids in the car scene in my area set their wastegate at a much higher psi for more boost = blown engines. They try to race their car with turbo with stock internals and it doesn't work out for them... wish they would see this video haha. Thanks for further in depth explanation!

[@ghettoflyer]

Congratulations! For making it on 1320 Video, and Car Buzz!

[@EngineeringExplained]

+ghettoflyer Awesome!

[@Phos9]

Suggestion: how about a video on how different induction methods are impacted by increasing altitude?

[@melody3741]

Phos9 you have to retune cars if ur in colorado

[@dezv4736]

Higher altitudes have lower oxygen density. It’s kind of the same reason a human who’s lived in parts of the world where they are closer to sea level, they have to adjust to higher altitudes. There’s less oxygen the higher you go. I hope that helps

[@dezv4736]

Just realized this was 2 years old oof

[@dontsubscribethanks]

@@dezv4736 if you have a turbo you most likely have some ecu you need to lessen the fuel

[@RobinRhyne]

I absolutely LOVE learning more about engineering. Thank you!

[@VoraciousPhantasma]

Can you please make a video about what happens when you put a car on a dyno in different gears? For instance, a 2k to redline run and how torque and horsepower change when the car is in 1st vs. 5th gear?

[@VoraciousPhantasma]

Really? So let's say I put a 200hp/200tq car on a dyno and do a redline run in 2nd gear which is 2.000:1. How would that change the dyno chart?

[@VoraciousPhantasma]

The_Bait So would the chart show 400hp/400tq or 200tq/100hp?

[@davidsunhun]

+VoraciousPhantasma your choice of gear does not change anything in the final numbers. Power = Torque * angular speed. If you change gears, both of the numbers change, so the power stays the same. Of course different gears have different efficiency, meaning that there is always power loss in the transmission, and the amount of power you lose is different in each gear. But that is why the dyno measures your power loss right after the run, so it can compensate for it and calculates the power at the crankshaft. (That's why power at the wheel is always lower than power at the crank). There is an other thing, which is that if you are in low gear, you have really high torque at the wheels, so you risk "jumping out" from the dyno (yeah, I know the cars are strapped down, but not always, and that's the reason why you don't have to strap down cars with low power figures), but the real issue is that the tyres may slip, thus giving you false information about performance, but more importantly, you cause tyre wear and dyno roller wear.

[@corsonp7727]

Agreed +davidsunhun. You are simply changing the gear ratio from the engine to the transmission, not the final numbers

[@VencedorGamer]

+Engineering Explained, I'm not a certified engineer, just an experimental fabricator, but I like your videos, you take the time to explain things without fast speech/mad gab/ancronyms like other KZbin personalities. So I enjoy watching, and learning from your videos.

[@alphabob8156]

Very helpful, crisp, and succinct explanation - thanks!

[@nickdibart]

I don't know much about turbos and always wondered what a wastegate was. I guess it is essentially just a pressure relief valve and a way to control the boost pressure? Thanks for the info.

[@Rocky-rm4bc]

+Nick DiBartolomeo yes that's is exactly what it is :)

[@melody3741]

Nick DiBartolomeo yes and no. it doesnt bleed off boost pressure, it reduces exhaust pressure to slow the rotating assembly down

[@melody3741]

usually pressure relief implies that the pressure it's relieving is the same pressure being controlled.

[@bernardinjean-loup1168]

Melody Absolutely correct!

[@CurtHousen]

Thanks for the knowledge I thought the difference between internal and external was how you vented the waste (in the exhaust vs straight to atmosphere). I think a little addendum is needed to clarify the terms wastegate and blow off valve

[@Snattle_Rake]

Absolutely wonderful videos! I've learned so much about cars, both for everyday use and for the fun of knowing racing applications. I love how far you go into detail (even though you sometimes go crazy with it like the lap time calculations.) So far I've been able to gather most of my knowledge in the books, but one day I want to take that further and make my own projects and learn the actual practice of working on and tuning cars.

[@chrisdanckert666]

Best ever series of enginering vidos will continue to use them in my classes

[@sadakotube]

How do we decide wastegate sizing? Usually someone just goes "you need this size."but is there some specific reason to go for a certain size? how do you know the flow required vs wastegate size?

[@BmanUltimate]

+sadakotube It depends on what amount of boost you think is acceptable, or what your engine components can handle.

[@sadakotube]

+BmanUltima was hoping to see the math or rationale behind it from Engineering explained

[@BmanUltimate]

sadakotube It's all engine specific, there's not one explanation.

[@crazydrifter13]

This mic is much better than the one used in twin scroll turbo charger video. I came straight from there.

[@salspec3381]

I'm not sure if it's been mentioned yet, but a video on boostcreep and boost spikes would be helpful. Bascially boost issues turbochargers can have for one reason or another.

[@jbronin23]

I appreciate your videos. I can always count on a better understanding on anything I'm watching about.

[@SteveBrownRacing]

Your videos have come a long way since you started. this is a good example of that progress. keep it up!

[@bwalyasapwe3397]

You are just so good at auto mobile engineering

[@damianstevenson1196]

internally gated turbochargers can also have the waste gate going to atmosphere.

[@sleeping2day986]

BOV not wastegate

[@CarsnStuff]

One of the other things for controlling external wastegates is since they have vacuum ports for both the top of the diaphragm and the bottom you can literally put just an 8 psi spring in and then buy a boost controller and running much higher numbers so you have the tune ability anywhere in between that. Also open wastegate dump FTW !

[@cybersteel8]

So when Dom pulled the vacuum line, basically the air going through the compressor doesn't reach the wastegate at all, so the compressor keeps spinning and emptying the air to atmosphere. This means that the exhaust gases will never bypass the turbo, constantly spooling it up and increasing air pressure. This would eventually blow the engine up because of the rapidly climbing amount of boost. But Dom did say that it would only have to make it to the end of the race!

[@pryderacing8056]

Sir, I appreciate the intel you provide. I have learned a great deal from you and I am grateful for the help. Keep up the great work!!

[@MrSapper21]

another great video from one of my favorite channels.

[@murffyslaw001]

Thanks for an excellent video. Right on point, no side tracking, very understandable, precise.

[@jasoncee666]

Awesome being able to go back years and get sound advice from my most trusted engineer, thanks buddy 👍😛

[@sumi7065]

great video, explains it without getting crazy technical

[@ruialmeida5217]

great videos! You can explain exactly the point, no confuses in your words. Sub from Portugal.

[@EngineeringExplained]

Thanks!

[@geulach]

I has a suggestion, how about making videos about f1 as it's just about to start, and explaining some bits and peaces on the cars and why how stuffs work etc.

[@chrissetter]

+GEULACH He has made several videos about certain mechanic operations of F1 cars

[@rlyons9109]

another advantage to external is less turbulence. Internal can cause turbulence in the housing, slowing down air flow. Which in turn slows the building of boost.

[@yourmothersfavouritehouseguest]

Internal wastegate turbos can also be routed to atmosphere, you just simply do 2 pipes, one for turbo exhaust and other for wastgate as you leave it open or even leave it without pipe :)

[@prasantamedhi]

Great video.. i was searching for an explanation and you my friend have explained it very nicely..😌😌😌

[@Nitrxgen]

You explain things really nicely and simple. Can you explain the differences in the sound with turbos when releasing acceleration? How it's caused? Some make the fluttering noise, some make a normal air release noise. What's the pros and cons in these setups?

[@nicky01324]

that depends on the bov (Blow off valve) hks sqv series are the most knowned for the flutering

[@DriftNick]

+Nitrxgen When the throttle plate closes (when you lift off the throttle) and there is no bypass valve or blow off valve the boost goes the only way it can which is back out the intake and over the compressor blades making the flutter sound, different turbos and intake designs can change the sound a fair bit to, best you could do is search on youtube for videos of flutter and the hks blow off valve to hear the difference as it's kinda hard to explain the sounds.

[@adjest6388]

That explanation was a little bit fast for an Asian who doesn't speak English daily like me but the diagram was pretty helpful in many ways ( of course, your words too ). Thank you ! :)

[@thenamesjonny9473]

I got your notification and dropped my phone now my phone is cracked. However EE do not worry I too am an engineer I'm ding some calculations to see how empty my wallet will be.

[@JT-kr3dg]

+ThenamesJonny Thanks man, your comment/fumble made my day lol. I'm about to upgrade so you can have my phone & lower your calculations.

[@EngineeringExplained]

+TheNamesJonny Really sorry about that! Shoot me an e-mail and I'll buy you a case for your current (or next) phone! :)

[@theCuki3M0nsta85]

+Engineering Explained that's legit!!!!!

[@JarHeadP3]

+Engineering Explained Well in that case...I dropped my nismo gtr...

[@thabg007]

if it's just the digitizer, it is easy to replace, I just replaced the charge port on my phone now it charges like normal again

[@Neurofunk81]

Internal wastegates can be vent to the atmosphere and external wastegates can be mounted in the turbine housing

[@chincemagnet]

I love your 4K videos. Keep em coming. Your videos have cleared up a lot of stuff for me that wasn't making sense for me. I'm upgrading my Evo X turbo, and I'm trying to decide which route I want to take.

[@guest98049]

DAMN EE BACK AT IT WITH THE GRAY HAIR

[@alisoleymani3987]

I do have a question. what makes that cool noise of turbos after letting off the throttle? is it the excess gas in the hosing exiting or is it because the sudden drop of turbine RPM?

[@rustybeatty6567]

The biggest improvements turbochargers need is to combine VGT/VVT with twin scrolls this would greatly reduce Turbo Lag and increase boost at lower RPM's and it would almost eliminate the need for a twin Turbo setup in most diesel engines and would help in inline 4 engines and when it is used in a Twin Turbo V6 and V8 gasoline engine configuration it would boost torque and increase horsepower without sacrificing much to do it especially in catback Turbo setup that is commonly used in the challenger and mustang and Camaro application basically the twin Turbos are installed after the catalytic converter.

[@robertfranqui6487]

The "Vacuum line" is not under a vacuum even at part throttle. There is no pressure drop from turbo entrance to turbo exit. If you use a manifold tap then you can have vacuum.

[@sixbone]

Would be great if you did a video on what an ECBS does and the advantages of 3 port vs 2 port.

[@StoneeVlogging]

What makes the turbos flutter?? Is there a waste gate that open and closes so fast that you get a flutter effect??? Is this a thing?

[@2JAYZ-GTE]

Adam Courchaine if turbo flutter does not harm the turbine, why blow off valves exist?

[@caleb29469]

2JAYZ-GTE it will harm the turbine . When the throttle valves close and there is no where for that air to go it will spike back through the turbine. Over time this will cause damage usually resulting in blades breaking off or premature wear of the turbine. Bov have their uses however bpv are generally more efficient.

[@the-real-zpero]

I've always wondered, instead of letting all that pressure generated while the engine was operating at a high rpm go to waste, couldn't you "store it" so that once you step on the gas again, rather than re-spooling the turbo you can spool it up faster using that stored pressure? Why try really hard spooling up the turbo, and then let a bunch of precious compressed air go to waste, it seems like it would be more efficient to re-use later... Thanks and keep up the good work! :-D

[@xGiLL]

+ZPERO isn't this sort of like an EGR valve?

[@javierriccardi]

ZPERO That’s pretty much how modern F1 engines work. The exhaust gases are used to spin the turbocharger and connected generator/electric motor on the other side of turbo which is used to store that same electrical energy to spool up the turbo. Like an electric supercharger. I wouldn’t be surprised if that technology eventually trickles down to the street level.

[@Shoeman90]

good vid but need to mention how an external is necessary for higher hp/boost applications because an internal cant regulate high psi as well and will cause overboost

[@chownkay]

Can you do a video on compressor wheels? Point milling vs flank milling. More blades vs less blades.

[@troyonufer2029]

I really enjoy your educational videos

[@EngineeringExplained]

+Troy Onufer Thanks!

[@RitzCifer]

Subscribed. Awesome explanation!

[@EngineeringExplained]

Thanks!

[@samhallieehrhardt9964]

that was excellent ! fast , clear and understandable ... thank u

[@carlwheeler5583]

Excellent video, short well explained and to the point. (Best of all it's about the subject and unlike so many other youtubers you keep your ego at bay 👍)

[@elaxel1469]

Engineering Explained. Is making a repro healthy for the engine?

[@jameswasher3938]

Such a great job explaining this. Thanks.

[@joeygreathouse3029]

Oh so this is why my preowned 2002 WRX goes "Whk-shhhh!" every time I let off the gas? It's dumping directly into the atmosphere, rad

[@DriftNick]

+Joey Greathouse You are confusing the blow off valve/bypass valve with the wastegate, they are not the same thing.

[@LeCharles07]

Make a video covering boost surge and creep. Pretty please.

[@derekt3923]

Very well explained, thank you 👍🏻

[@AJTalks]

I am considering an external wastegate for my 2015 WRX, and I had a few questions. How would it effect the reliability of the car? Why is it that so few people do this modification if it improves turbine efficiency? And lastly, would you ever do this on your STI if your warranty was not at stake?

[@C0fff]

+Alex Johnson It should not affect reliability in any way. As for why people do not do it, it costs money. Also in a version that dumps to the atmosphere, it is illegal in the majority of states. They are often for aftermarket turbochargers as well which require more airflow.

[@KiNG-fr5ib]

+Против Глобал What? Are u sure? Because i think wastegates are made to dont let the turbine overload. Im not an expert tho

[@yogaexe]

+Alex Johnson because if you dump it to atmosphere, its illegal. And to re route it back to exhaust means more piping needed. 2015 WRX turbo is mounted in a very tight space if you are adding a bigger twin scroll turbo with external waste gate, you will have 2 big waste gate under your car. If you want to re route the it back to exhaust, the piping will be nightmare.

[@SuPr3meFX]

+Против Глобал Nope

[@SuPr3meFX]

***** First :)

[@christopheryang9735]

Could you do a video on differences in a electronic waste gate and non electronic waste gate. Or can you do one on the differences of a waste gate and blow off valve and why you would use one over the other?

[@3dscott]

How do you know what spring rate the external waste-gate is set at.

[@ChrisRollins]

i have a fiat 500 abarth. would the waste gate be the cause of a short, very quick drop in boost during acceleration around 3500 rpm?

[@ahmedshrief2263]

Thank you for your effort and time, very useful video

[@Dazza-gp6we]

Aw man I finally found a video I can understand. Hell yea

[@ianmansfield8885]

great simple explanation.. if you haven't already done a couple of flat plane v8 / regular v8 motor explanations or examples could you please thx

[@beni8602]

Thanks for posting this. I was recently wondering why the Bisimoto 930 Twin Turbo had what looked like an extra pair of smaller exhaust pipes. He must just be dumping the wastegate exhaust into the atmosphere. I wouldn't have figured that out without your explanation.

[@jacobbishop9012]

I’m very confused. Apparently there are blow off valves, bypass valves, internal waste gates, external wast gates, and turbo flutters.

[@iceboy121]

great video man, I'm always learning something new!

[@richardcollins1217]

Have you done a boost controller video yet? That would go along with this nicely.

[@mitchellrobertson15]

+Richard Collins Agreed, a lot of confusion in the comment section here.

[@vzr314]

Hello Jason. I think it would be nice if You make a video about blow off valve, usage and how it works. It would be a nice to watch in addition to this video. I know that out there already may be other videos that explanes blow off valve, but not in your unique whiteboard style :D

[@X11CHASE]

At roughly 1:20-1:27, this should make it clear to everyone why boost creep occurs.

[@tony21227]

Perfectly explained

[@lambosrkwl]

I would have thought that it would be beneficial to have the bypass valve operate as much like a switch as possible, either fully open or fully closed but not partly open under pressures below the target boost threshold. However the pneumatic actuator/spring design seems to imply that the amount the valve opens is linearly proportional to the boost pressure, have I missed something? Also what are the advantages of using a diaphram over a piston? It would seem to me that a piston would be more reliable, is it just down to cost?

[@kringlefanten]

You should discuss the difference between pneumatic and electric wastegates and why electric is better for high power output.

[@fullmetalflix5195]

Very informative thank you I truly do learn from and enjoy your videos your wisdom enlightens us all :)

[@MajdSindi96]

you forgot one advantage... SOUND

[@willargus]

This popped into my head while I was watching the video, but do they make waste-gate values that are not passively pneumatically actuated? For example would it be possible to create an electro-magnetic waste-gate that can be controlled via a computer from inside the car, allowing for different settings, ie: a higher PSI that would create more power but also more stress on the engine for racing or sport-mode applications and a lower PSI option that would be used for daily driving? Thanks, and great video as always.

[@EricBentleyW]

+Will Argus Well, a boost controller is a bit different in that it's not really an electronic wastegate, but you can buy electronic boost controllers that change the pressure that goes to the pneumatic wastegate. The functionality is the same as you've described however

[@mcbeth590]

How does rerouting the external wastegate back into the exhaust help the turbines performance?

[@ShawnDickens]

It doesn't help performance ever. It does help with emissions. Running it into the exhaust further down you don't mess up the vortex in the pipe coming from the turbo. If you run if far enough down where the vortex has changed to just a straight flow the performance lost will be minimal. This vortex coming off the turbo is the only reason the very large exhaust pipes make more power on turbo motors even passed when it would normally just be a waist of space and money on other motors.

[@brandonh4832]

Is there any benefit to having the excess gas released into the atmosphere, compared to further down in the exhaust, with the external waste gate?

[@Rocky-rm4bc]

+Brandon Horn probably yes, since the gas will not have to pass through the exhaust itself (less restriction) hence quicker release of exhaust fumes from the engine. this is just how my logic would define it, if im wrong please do correct me :)

[@neilcastelli7505]

Awesome explanation and video

[@lastsc7429]

Could you please explain how the size of the waste gate impact the pressure & overall performance of the turbo charger?

[@KitsuShadow190]

Can you do a video specifically on turbine design?

[@8000blue]

Why do you not get a oscillation of the was gate when the waste gate opens and the pressure drops. E.g the waste gate fluttering open and closed

[@venkatpuneeth]

But what's the real reason for using a waste gate ? Why are we bleeding out the exhaust gases ? Is that to regulate the intake manifold pressure ?

[@Thunderstormworld]

new tech turbo waste gates are operated with vacum from a vacum pump bolted on the camshaft and electronic via the ecu and sensors which makes it slightly more difficult for the backyard (ricer) mechanic to fiddel with.

[@Thunderstormworld]

Which is a good thing

[@DRKILLIE]

Would dumping the excess from the blow out and waste gate into the exaust help or hinder scavanging?

[@MAYURGUPTA9]

Thanks....it was explained nicely

[@PANTYEATR1]

can I request a video on blow off valves and how to properly set one to work effectively? thanks

[@Rocky-rm4bc]

+PANTYEATR1 you can't make it ineffective unless you set it to open at a way higher boost than you actually get :D

[@PANTYEATR1]

+Rokas Getautas thanks for the reply, but i heard issues with the bov bleeding turbo pressure and not allowing the system to make the boost you want it to

[@Rocky-rm4bc]

PANTYEATR1 not entirely sure about that one, mate. Best thing to do is to research on the topic. yesterday I found out that it would cost over 2500 USD to buy a turbo kit for my ga16de powered Nissan Primera :D

[@clintbalzan8926]

So when you start the engine, the wastegate will automatically close when the rod is moved?

[@elgrandecaro]

What would be the down side of eliminating the waste gate and just controlling boost pressures via BOV? If any.

[@PAINACAB]

hi. i like your uploads. very informative . keep up the good work. cheers mate!

[@MrCrankyface]

Great and informative video, thanks!

[@Brunmed]

Fast and simple, nice!

[@NuclearFishin00]

It would be really interesting to see your take on the Formula 1 MGU-H system. I understand that system absorbs this excess energy that would otherwise be flushed out the wastegate? It's hard to find articles online that detail how the MGU-H functions from an engineering perspective; seems like a perfect one for you!

[@EngineeringExplained]

Check out my video "2014 F1 Engine" :)