turbos we all love them they're the magical snail-shaped power adders that can turn even an average engine into a fire breathing monster but how do these bad boys actually work and what exactly are the pros and cons going turbo today on autoab we're going to find out turbos aren't actually really all that complicated and they've been around for over a 100 years back in the day this guy had a genius idea he realized that you could use an engine's exhaust gases to drive a compressor which would then shove more oxygen packed air into the cylinders making them even more explosive they were first used on diesel engines in the Marine industry and then started getting used a lot more on aircraft engines around World War I so that fighter planes maintain sea level performance at an altitude where the air is thinner AKA turbo normalizing when a turbo is used to exceed ambient sea level pressure figures that's called turbocharging automaker started playing with turbos back in the ' 50s and we got the first production turbocharged car in 1962 and it didn't take long for the hot roders and Tuners of the day to get their hands on them either but before we dive into how this spoolie boy works we got to break down the basics of an engine picture an engine as a massive air mover or pump it sucks air and fuel into a cylinder then compresses and combusts it before blowing it out also known as suck squeeze bang blow at its core getting more power out of an engine means burning more fuel which makes the explosions in the cylinders bigger and better but here's the catch without enough air that extra fuel is about as useful as Brad with a wrench adding more fuel is easy but how the heck do you get more air see an engine is limited by how much air it can move AKA it's displacement one way to pump more air is to build an engine that has larger cylinders problem with that though is Big engines are heavier typically slower to rev and about as Nimble as a sumo wrestler but there's no replacement for displacement am I right wrong a turbo makes a small engine flow more air making it capable of making the same power as a much bigger one so you can think of a turbo kind of like an on demand displacement modifier so here's your turo looks like a snail but don't let that fool you in fact this B is capable of spinning in excess of over 100,000 RPM exhaust gases from your engine enter here and spin this turbine wheel before getting shot out your tailpipe the turbine is connected to a compressor wheel on the other side and as it spins it sucks in fresh air crams it down your engine's throat and voila more power but not so fast because all that exhaust and moveing air means turbochargers get really hot the turbine side which we affectionately call the hot side more often than not looks Rusty because it's basically operating like a mini Blast Furnace the extreme heat acts like a catalyst and causes the metal to oxidize more quickly and the cold side isn't actually really all that cold when air is compressed molecules are forced closer together which causes a bunch of friction all that friction makes the air coming out of the turbo hotter than a Hot Pocket in an Easy Bake Oven oh the thing is hot air isn't dense and dense air is what we want that's where intercoolers come in an intercooler is like a radiator for your turbocharged air it sits between your turbo and your engine and forces the air to pass through Channels with cooling fins cooler outside air passes over those fins extracts the Heat and cools that compressed air right back down packing those molecules closer together and feeding your engine the dense oxygen rich air it craves oh and that hole in your hood isn't just for catching birds it keeps your in cooler Co too but what keeps a turbo from just spinning itself into Oblivion that my friends is where the waste gate comes in it allows exhaust gases to bypass the turbo to regulate its speed and boost pressure when maximum boost pressure is reached or when you let off the throttle the wastegate opens up and allows all that exhaust to just cruise on by but that's not the only thing that controls boost pressure the waste gate can't do anything about the already pressurized air in your intake system when you jump off the throttle well all that pressurized there has to go somewhere and ideally we don't want it slamming back into installing the turbocharger and that folks is the job of the blowoff valve off throttle or when over boost the blowoff valve opens up and fents all that pressurized air back into the atmosphere some designs use a diverter valve which keeps all the air in the system so your car's engine computer doesn't have to do complicated math to keep your engine running right we'll make another autolab video explaining mass airf flow sensors and engine controls but we're getting off track so in theory if a Turbocharger flows air and more air leads to more power a bigger turbo should mean bigger power right unfortunately it's not that simple ever heard of Turbo lag it's the awkward pause between stomping on the gas and actually feeling boost it's like waiting for your Internet to buffer right before the good part of a video bigger turbos flow more air but they also take longer to get up to speed and on something like a small four cylinder that doesn't flow a lot of exhaust gas on its own a bigger turbo isn't always the answer Engineers tried to solve this with twin turbos twins basil twins but they didn't stop there there are parallel turbos sequential turbos two-stage turbos compound turbos variable geometry turbos and now there are even turbochargers that are electrically assisted now real quick if you guys love turbos as much as we love turbos we check out these limited edition turbo t we got the ice cream drip turbo te and the don't die turbo te check them out before they're gone links up here or down in the first description now let's learn about the different types of turbos when it comes to using more than just one turbo parallel turbos are the simplest one turbo per cylinder bank and to keep both Banks balanced you either have the turbochargers power their opposite Banks or you combine the charge air together as it enters the engine early twin turbo cars like the Maserati by Turbo Nissan 300Z and mitubishi 3000 GT all used a parallel Turbo System but sequential or two-stage turbos are where things get spicy with this design a smaller turbo spools up quickly for instant power then hands things off to a larger turbo for That Sweet sustained boost at high RPMs the 80s and '90s were the Golden Era of turbos like this back then turbocharged cars were like rock stars temperamental loud always on edge think cars like Audi's and Group B racing or street cars like the markv Supra fdrx7 compound turbos are the same with one small turbo and one bigger one but the difference is the exhaust gases flow through them in series The Little Turbo's only job is to help get the big turbo spinning this configuration is most commonly found on big diesel engines we've all seen the videos of big compound setups then of course there are very variable geometry or variable vein turbos which can modify the flow of exhaust gases hitting the turbine wheel at lower engine speeds the veins move to a narrower angle which increases velocity and Spins the turbo up faster to reduce lag and at higher RPMs those veins can open up and allow more exhaust flow which optimizes top end power these were first seen on cars like the Fiat chroma and launcha Delta integral and 993 911 Turbo and now with cars like the 911 in GTS we even have electric turbos and I'm not talking about one of those 12volt snake oil turbos you get on teu or wherever the cool kid shop these days but a real 400 volt electrically assisted turbo that can be spooled instantaneously essentially eliminating turbo leg it can also be used as an energy recovery unit and if you want to learn more about it then go watch this video right up here turbochargers used to be reserved for race cars and the hottest most performance oriented cars on the road but now turbos are everywhere from your mom's grocery getter to your dad's pickup and of course some of our favorite super cars and they're not just used for performance anymore but also to boost efficiency the pros seem pretty obvious there are a few cons though extra weight more complexity more stress on the engine and more heat under the hood to name a few with that said though these days turbocharged cars are extremely reliable and it's estimated that of all combustion powered cars sold this year roughly 40% of them are turbocharged and there are plenty of turboed cars in production right now that aren't exactly thrilling to drive but for a lot of them you're only a cell phone few hundred bucks and a quick remap away from letting that inner turbo power shine so go out there and reflash your mom's wolvo just don't tell her I told you so if you enjoyed learning about turbos hit that subscribe button and give us a like we've got more videos on everything from engines to exhaust to tuning and suspension and maybe even some stuff your mechanic doesn't want you to know if you want to learn about the difference between a Turbocharger and a supercharger well click this video here or go watch Brad run through some of the best cheap cars that have insane tuning potential right here my name's Trav thanks for hanging with me today on autolab see you all with a fresh video next week [Music]