Why Your Engine Isn't Twin-Charged

What do a $1.8M supercar, a Group-B rally monster, and a tiny, hundred-horsepower hatchback have in common? They’re all twin-charged: They have both a supercharger and a turbo. A true KFC Double Down sandwich of power. And this decades-old design could be making a comeback. On this episode of B2B, we’re gonna figure out why you would double-down on forced induction, and why so few cars have ever been twin-charged. Turns out, mo’ charging might just mean mo’ problems.

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[chrispy]

Jeremiah, please do an episode explaining different gear ratios on differentials, transfer cases and transmissions; how different parts affect the ratios; and how it affects speed and acceleration.

[JakeyJakeThree]

Love twin-charged.... Don't forget about Volvo's T8 engine: 400hp 500tq twin-charged four cylinder hybrid! Would that be triplet charged?

[nothingbeatsawoodie]

As always volvo is forgotten. I tested the volvo s90 t8 when it came out in 2017 and got amazed by it's supercharged and turbocharged four cylinder engine, first engine of it's kind i saw and drove. It is a beast

[vaporlockwwl]

Detroit (and I think Cummins) made twin charged engines in the last 30 years. The Detroit had 12L+ of displacement and I believe the force induction system was making like 75lbs of boost. The horse power numbers weren’t particularly impressive, but they produced well north of 1, 000ft-lbs of torque

[justindesrosiers]

I absolutely love the Delta S4. It’s just so monstrous, wild, uncontrollable, blasphemic. It was so fast (0-100 in 2.7 second on gravel) that even Henri Toivonen, the legend himself, was barely able to drive it.

[carsnquads]

Group b rally was absolutely the best thing ever. The technological advancement made in the few year it was around was amazing

[Mitsuman]

Working on Volvos for the past two ish year they’re amazingly designed even before the hybrid they had dual charged motor with beautiful power delivery throughout the rpm’s the new 48v hybrids don’t even have a exhaust manifold the turbo models have the turbo bolted right to the head

[codylujan]

after a certain year, BMW caught on to "turbo lag" and decided to have an option on their M vehicles to "pre-spool" their turbo's. Instead of waiting for a certain RPM to get your power, you can put your car into "sport plus" mode and instantly hear the turbos spool up. When you hit it at a red light, you're not losing any low end power.

[Ezmeon]

I was recently doing some research and found out that my dad's Volkswagen Scirocco actually has the 1.4L Twincharged engine.

[markwerner]

People who have the Volvos with twin charged engine: 👁👄👁

[GTAGUY]

Twin charging on the other hand has been used quite successfully on many aircraft over the years, and those dudes went nuts pulling every oz of power they could. Back as early as WW2 we had engines producing up to 3000hp give or take, though the engine I have in mind I believe had multistage supercharging instead of being twin charged, but I digress.

They also have a fielded a few special kinds of turbochargers implementing a power recovery turbine, that not only spools the compressor but has a shaft connected to the turbine (some may have a second) that inputs additional exhaust gas energy back into the crankshaft.

[feralmr]

Been doing 'full compound' twincharging on 4ag engine since 2007. The whole rev range powerband is awesome! Torque forever. Mines only budget diy setup, but works awesome.

[ariceff]

Every Volvo since 2018 has a 2.0l 4cyl with a turbo, and the higher trim option are all twin charged. So you can get a mid size sedan with a 350ish hp twin charged engine. And if you get the hybrid it's like 400hp with the mechanical drive to the front wheels, and electric driving the rear.

[Ligo]

Don’t forget about Volvos T6 and T8 engines they’re twin charged four bangers making 320-400 hrsprs

[spartan]

Thanks for explaining the way the system works. I've wondered and speculated since I got a car that had one in 2019. Speaking of, you forgot one of the major and only brands making twin-charged engines right now; Volvo.

Volvo also makes Twin-charged engines for both Semi's (I think a certain D13 model) that produce over 1500 ft-ibs of torque and around 400 hp and for cars their "T6" models past 2016 which are 2.0L Twin-charged engines that produce about 306-330hp with equal amounts of torque.
their hybrid "T8" also uses the twin-charged engine and produces a combined 400-415hp as well and around 475ft-ibs of torque. Not going to forget the rare 2015.5 S-V60 Polestar line that used the 2.0L Twin-charged setup to produce about 360+hp also Just before Polestar split into it's own car making.

As someone who owned a 2019 Volvo XC90T8 hybrid, I can say the acceleration was absolutely insane and I never experienced any form of turbo-lag. It also got fantastic gas mileage, even when not in hybrid/electric mode.
That said, my favorite engine is still the Yamaha 5 cylinder inline Volvo used from 1995-2012ish. Specifically the one in my 2007 S60R which has a 2.5L that produces 300hp and 295 torques. The turbo-lag is quite noticeable though at low RPM, but it's boot threshold is only 1850 RPM, which is nuts.

[andrewm]

Thank you Jeremiah for talking about such a little known thing. Man i love twin charged cars

[skythundersky]

Yo I just wanna thank the entire Donut team for putting out this amazing content for years on end. I literally wouldn't know where I'd be car knowledge wise without you people. The editing, the topics, the way of presenting them, everything. I mean, how do you even come up with some of these topics? That one JDM van that's getting banned, this right here, fucking BOATS?! You just can't not love and appreciate the stuff all y'all create!

[damilolaakanni]

Donut Media: Twin charged engines.
Volvo:👀

[rhidiandavies]

I had one of those VW 1.4 tsi engines in a seat ibiza cupra until last year (I don't think you get them in the US) and absolutely loved that engine. Got 45 mpg on long drives but would pull like a mule from 2500rpm right the way up to 6500rpm. Great little motor and plenty fast enough to get you into trouble...

[dougwhyland]

Great video! That Audi diesel you mentioned is actually tri-charged, some pretty cool tech. 4 valves per cylinder, with dual exhaust runners from each cylinder, driving two turbos. One set of exhaust valves can be silenced, by moving the cam. All the exhaust drives one turbo bringing it up to speed quicker. When that turbo reaches max volume, the valves are engaged spinning the second turbo. The third compressor is electric used just for throttle tip in.. reported to have less throttle lag than a naturally aspirated engine.. to spin the electric compressor quicker and keep the electric motor smaller the car has a 48 volt system. Wish they could import it to the USA.