Honda RA617H power unit, 2017

Why F1’s unloved V6 hybrid turbos won a reprieve for 2021

2021 F1 season

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The V6 hybrid turbos have achieved incredible results since they were introduced in 2014. Peak power output is now in the 1,000bhp region – levels that haven’t been seen since the last years of the normally aspirated V10 engine era, when cars used almost twice as much fuel.

But this efficiency is arguably why the units don’t make for great racing engines. The units are complicated to manage during the race and some have criticised the less raucous noise the engines make compared to the V8s which preceded them.

A little over a year ago the FIA and Formula 1 management announced plans to overhaul the sport’s engine format in 2021 to address these and other criticisms.

The plan was to remove a key component of the hybrid drive train – the MGU-H – which generates energy from heat. The MGU-K was to be made more powerful and drivers given greater control over its operation, to counter criticism that the racing has become governed by the pit wall. And the rev limit would rise to 18,000rpm to create a more dramatic sound.

But after further negotiations between FIA, FOM and the teams, the MGU-H is now set to stay. Why the U-turn?

Ferrari and other manufacturers lobbied hard for the MGU-H to be kept, having spent nine-figure sums on its development. Manufacturers were especially wary of the potential ‘double whammy’ of needing to develop the current engines until the end of 2020 while building completely new units for 2021.

Chase Carey, Circuit of the Americas, 2018
Liberty’s plan for a 2021 rules revolution is turning into the usual F1 fudge
When hopes were dashed that a new engine format would attract new manufacturers to the sport, the key reason for changing the formula was lost.

According to FOM CEO Chase Carey, discussions between F1, the FIA and the teams led to the conclusion that criticisms of the current power units through other areas of the rule book without making fundamental changes to engine specifications which lead to costly new developments.

“From early days our goals on the engine were: simpler, cheaper, louder, more power,” said Carey during a call to investors. “Let the drivers drive.”

“A year ago we were probably heading towards a towards a more significantly rebuilt engine,” he added. “As we got into discussions we, with all the teams, came to an agreement that the right path was more stabilising the existing engine and marrying it to a series of sporting and technical regulations that improved competition and helped improve address the economic issues around that.”

The fine details of the rules is still being worked on, said Carey. “I’m sure there’ll continue to be regulations that evolve with that. But I think the engine path we’re on is pretty well agreed to and continuing to be refined through the regulatory process.”

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But the concern remains that as F1’s engines are so sophisticated and specialised, and the current manufacturers have been racing them for almost five seasons, that any new manufacturer coming in would be at an enormous disadvantage. By allowing the current competitors to keep the same format, has F1 guaranteed no new manufacturers will appear any time soon?

Carey believes the focus on keeping costs down, which the new rules are intended to achieve, will apply to existing and new manufacturers equally.

Porsche 919 hybrid V4 engine
Porsche, which raced a V4 hybrid in WEC, turned F1 down
“That’s why the regulations are important. I think what we what we really came to an agreement with [is] everybody got persuaded by the stabilising.

“When you have a new engine, everybody starts over and there are always unintended consequences out of a new engine. A factor for example that came out of this is dyno time, which is probably one of the more expensive consequences because it lets you test open-ended or just throw stuff against the wall and test it.

“The degree you want to address how much how much time and money can be spent testing an endless list of theoretical enhancements is probably an example of as important as anything to try to make the engines, both from a competition perspective and a business perspective, viable and attractive for existing and new players.

“The intent of this was not just to improve the path for existing [manufacturers] but actually to develop a path that we think is enticing and interesting for new [manufacturers].”

Another factor in the decision to keep the current engine format was a desire to ensure F1 remains at the cutting edge.

“The technology in this sport is incredibly important,” said Carey. “We have technology that is miles beyond any anything else out there at any level on the efficiency these engines.

“One of the stories that has been told well enough is this new hybrid engine that came out a few years ago, the incredible performance it gets today with a much more fuel-efficient basis than prior engines.

“We wanted to make sure we continue to have the hybrid engine that was road relevant today but at the top of the pyramid in terms of technology that in many ways is at the forefront of what’s going on in the world. So I think it’s achieving all the things that I think that part of that is what attracts the right new engine manufacturers into it as well.”

Carey described the discussions between the parties as an example of the kind of consensus-led solution Liberty Media want to govern F1 by. We’ll have to wait until 2021 to discover whether the light touch on the 2021 engine rules meets their goals or turns out to be a compromise too far.

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Keith Collantine
Lifelong motor sport fan Keith set up RaceFans in 2005 - when it was originally called F1 Fanatic. Having previously worked as a motoring...

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46 comments on “Why F1’s unloved V6 hybrid turbos won a reprieve for 2021”

  1. Can’t say I’m too upset about this decision, the manufacturers are getting closer in performance all the time and there’s still improvements to be found, there’s no guarantee that would be the case with another big change.

    The noise has never been an issue for me as I don’t see it as important to the racing, just a side effect, but removing fuel and rev limits is no bad thing.

    If anything I would like to see less restrictions on engine development and let teams try different ideas but obviously costs have to be taken into account.

    1. @glynh, I wonder how much of this comes from the fact that the current fan base is biased towards those who grew up in and seem to worship the 1990s with a sort of blind fanaticism.

      It is extremely tiresome to see the same rants by those who seem to have permanently fixed their belief of what the sport should be based on what it was like nearly 30 years ago now, almost as if it has become a sort of safe haven for those who cannot cope with the modern world and wish to escape to a fantastical version of their childhood where loud screaming engines can be used to drown out that which they do not want to hear. Even the authors of this site seem to be rather prone to biasing their coverage towards that same market and seem to hold that period with a less critical eye than they should.

      1. Actually it’s not Conservative poletics, it’s people who want competition, excitement and entertainment from motorsports ‘supposed’ highest category. It isn’t offering much of that other than ‘names dropping’ itself as the best category in motorsport, which it is far from in sound, action, even driving ability now. I’m 36, I want the cars to race closer, sound better, I want a show. In the 90s it wasn’t much of a show either, but now we have the Internet to complain. At least it sounded great.

        1. They sound better now IMO.

          1. yeh sure. im open to bad sound, I would love for f1 to go Full electric, and beet other series to it instead of this stop gap effort that has turned away racing teams and manufacturers.

          2. @Yaru They sound better than 2013, but I don’t think better than the early-mid 1990s. You can’t beat variety.

      2. There also other people that simply cannot accept others opinions, and opinions, inherently have a big layer of emotions, nostalgia and personal perspective.

        I, for one, adore the sound of racing cars, and the current models lack a lot in that. If that’s blind fanatism, then so be it. I like loud engines, sue me!

        1. F1 is a dead sport. Just like black and death metal died in the 90’s, so has F1. Realistically, in it’s current form there is nothing more to explore or convey here. It is simply a lesser rehashing of what came before. No spirit or fire anymore.

      3. Having been to the 2018 USGP, I can say that the engines sound much, much better than on TV. The real issue with the sound is that the TV coverage does a really bad job of capturing it. But if anyone has never been to a race live and just watches on TV, I can understand why they don’t like the sound, because the product on TV is just awful.

      4. @anon Well, the 1990s were something of a golden age in this sport, and there’s no denying that. When you think about it, haven’t some elements from that era returned? We have wide cars again, big wings, wider tyres – all of these since 2017. We are to get simpler, cleaner front wings with straight endplates and bigger and taller rear wings.
        If F1’s future rules decisions were governed by the 1990s, you don’t think there would be engine variety, e.g., you can show up with a V6, V8, V4, I4, or even a V12 if you want, as long as you have the same fuel allowance. And I think that would be great, and it would really bring in a few new manufacturers.
        I would go even further – how about some ground effects and getting rid of some arifoil for the sake of good racing? The late 1970s and early 1980s were good too.

  2. One thing to note is that the current rev limit is at 15000 rpm but no engine has allowed for shifting at over 12500. The fuel flow rate is what kills it which seems idiotic because you already have a maximum amount of fuel per race. Even removing the flow limit will need a redesign of the engines which in my opinion has to be done.

    1. I think keeping the fuel flow restrictions and relaxing other parameters, e.g. engine capacity and configuration, may be an incentive for other engine manufacturers, e.g. Porsche and Toyota, to consider supplying F1.

  3. The problem with v6 is the sound, any hybrid can make power, but the choice of v6 was terrible, especially with turbo added. Even 4 cylinders/turbo would have been better. V8 hybrid would have been ideal, or v4 hybrid. Amongst road cars v6 consistently sounds the most boring, especially turbo ones. Straight 6 is so much better. The road car relevance is a heap of crap, as even Mercedes are going back to straight 6 instead of v6 for road cars. Some here will say they don’t care about the sound, well good for that minority. There will still be a gap from best engine to worst in 2021, this has been the worst formula for competition amongst engine makers, it favoured from the start those that saterted development early, 7 years after Mercedes started developing they are still top.

  4. Road relevant is one of the biggest nonsense words around. What they really mean is marketing relevant.

    1. Or head start in development which can be approved quicker by the greedy manufacturer’s CEOs who want to make money and don’t care for a level playing field. F1 is a disgusting out of date formula, but we keep watching

      1. @aapje @kpcart Marketing relevant is fine too. Racing wouldn’t exist without marketing, without sponsors. Manufacturers aren’t necessarily greedy (of course some are), but like all businesses they exist to make money, and they are the employers as well. Greed only goes so far until they price themselves out of the market, monopolies aside of course. It is not evil for a company to strive to be the best and to be profitable. It is what makes the free world go around. It is what pays people for their education and talent, and pays shareholders, who then support their families.

    2. ‘Road relevance’ is as real as it gets, @aapje.
      Thermal efficiency (fuel efficiency for road cars) is one of the most important areas for development for non-electrical cars.
      Most new cars now have (multiple) turbo’s, and even my non-hybrid car has some hybrid features (not sure what it means but the fuel efficiency display shows ‘charging’ when I lift the throttle).
      MGU-H is the next thing for road cars, with some already having this technology (e-turbo).

      Unless we all move to battery electric cars soon, all the learnings of the F1 PU remain ‘road relevant’.

      1. even my non-hybrid car has some hybrid features (not sure what it means but the fuel efficiency display shows ‘charging’ when I lift the throttle)

        @coldfly – Interesting, what care make/model? That sounds like your car’s alternator is activated when coasting, and deactivated on throttle (and when the electrical demand is low).

        all the learnings of the F1 PU remain ‘road relevant’.

        I agree that there is trickle-down from F1 R&D into what goes into our cars, even though “road relevance” has been so over-used a phrase that it has become a bit of a punchline, like “pinnacle of motorsport”.

        The one thing is that for such technology to reach mainstream/mass-market cars takes time due to the need for costs to come down. I think we are at an interesting inflection point where the common uptake of electric cars might actually occur sooner than those F1 technologies coming into ICE-powered cars.

      2. even my non-hybrid car has some hybrid features (not sure what it means but the fuel efficiency display shows ‘charging’ when I lift the throttle)

        AFAIK On cars like that, the alternator is managed so that it charges the battery more while braking, and less (or not at all) when not. It’s a minimal form of regenerative braking, reducing the fuel used to charge the battery.

      3. The way f1 achieves its high efficiency is not compatible with how normal engine operates. Race car engines operate at full throttle, high speed, high rpms with constant acceleration or deceleration. Road cars cruise at low rpms, accelerate at half throttle. And nobody is really even making v6 engines anymore. Road relevance is just an invented word for something that needed to be invented for the current engines to make sense to someone. As a racing engine the current engines are pretty much a complete failure in every aspect. These engines have made everything worse.

    3. @aapje It’s only a nonsense phrase to those that don’t understand what the term actually refer’s to & why it’s something manufacturer’s see as been important.

      It’s not so much about taking parts of a race engine & transferring them onto a road car, It’s about things like manufacturing processes, Materials, Reliability improvements, Oil’s/fuels etc..

      1. @gt-racer For sure. And we also do have the literal direct correlation between road cars and F1 cars via hybrid systems. They were already in domestic cars before F1 applied them, and now F1 can be a part of the global R&D going on towards greener power. I think Hybrids are going to be here for a long time, at least until electric domestic cars can go 800 km on a charge and do it again after a quick 5 minute stop for a recharge, like ICE cars can do now. It is so much about practicality, and for now an awesome solution is to have stingier and stingier ICE’s charging batteries on the fly that power electric motors that actually add HP and take load off the ICE.

        1. Most people’s day to day driving in the UK is limited to a 30 mile round trip, with only occasional trips over the 100 mile mark.

          I’ve often thought that it would make sense for an EV manufacturer to include, say, 2 weeks worth of car rental power year for the first 3 years. That way a person has the car they need regularly, plus enough for a 2 week road trip every year.

      2. @gt-racer

        It’s not so much about taking parts of a race engine & transferring them onto a road car, It’s about things like manufacturing processes, Materials, Reliability improvements, Oil’s/fuels etc..

        But all of those things are mostly extremely different from road cars. Formula 1 uses very expensive manufacturing processes, materials, oils and fuels that are unaffordable for road cars.

        1. @aapje They are different & expensive but you can still learn a lot from these things & some of it can be transferred to the road division & actually there’s sometimes stuff from the road division which is usable by the race team.

    4. petebaldwin (@)
      10th November 2018, 17:03

      Road Relevance means that in order for manufactures to make better road cars sooner, they have to sacrifice the things that would appeal to casual fans – loud and exciting engines, drivers pushing their cars to the limit, close racing throughout the field etc… The problem is that it goes completely against Liberty’s goal of bringing in new, casual fans.

      Try explaining to a non-F1 fan why watching the drivers tip-toe around trying to save fuel, not to put any stress on their engines or gearboxes or damage their (deliberately awful) tyres is fun…. I didn’t need to have it explained to me as a kid because the sound of the engines got me interested. From there, I got into the complexities of the sport. There is nothing to latch onto in the first place these days….

  5. I do wonder what Ross Brawn’s thoughts are on this. I wonder if his name wasn’t mentioned because he didn’t like the decision.

    I thought trying to get more teams on the grid and lowering the amount of money the teams spend was part of the reason why the dropping certain parts of the hybrid system was attractive.

    1. @docnuke I’m quite sure Brawn is exactly on board with this. He’s all about getting the teams on board with F1’s future, and after discussions with all the teams, this decision to keep the MGU-H for now, is the best way forward for all. Carey is the one being interviewed above, but Brawn is the one who has been the conduit between Liberty and the teams, as he has been hired to be.

      It turned out that dropping the MGU-H was not as simple as just taking it off the Pu. It would require more redesign and expenditure than they originally thought. So there would be quite the expense to dropping it, and at the same time with stability in the regs comes a chance for all manufacturers to get closer to each other, as well as have their massive R&D money they’ve been spending these last 5 or so years, spread out over more time.

  6. If Red Bull had not had a hissy fit about their engines there would have been no call for new engines (even those who moan about the engines for lack of noise only hear the sound of the engines via the TV 95% of the time; i.e. their home race, so are hardly missing a visceral experience). Now that Red Bull have a new engine for next season their desire for additional engine manufactures has evaporated (unless Honda can power them to victory). ‘New engines’ was always a political ruse by Red Bull to get them out of the very deep hole they had dug themselves into with Renault which also poisoned their possible relationship with either Mercedes or Ferrari.

    1. To correct my description, at the home race spectators hear the engines ‘live’ which if they do not attend any other F1 races amounts to only 5% of races, the rest of the races will be heard via media (TV, computer etc) 95% of the time which inevitably mutes the experience, so the noise of engines or lack of it is a red herring.

      1. Having attended this years US GP, I agree. I was sitting in the section with the slow corners after the back straight. Even though the cars were at their slowest it was still more exciting than watching the race on TV. The camera angles make the cars appear so much slower – I know it’s for sponsors, but come on.

        And then there’s the sound. Since 2014 it’s like they decided not to change the sound recording from the V8 engines era. The cars sound good live though I do prefer the V8s, having been to the 2013 Canadian GP. The sound isn’t that big of an issue.

        But if you watch F1 only on TV I completely understand why you’d be upset because the TV coverage is awful. What needs to be fixed is the broadcasting because they fail to capture the sound properly. The Sky commentary completely drowns it out because they always need to keep talking.

  7. I always loved the V6 Turbos, glad they are staying.

    1. Also I honestly preferred this to the old NA engines. When they made the change some years back, I preferred the newer sounds.

      I’ve attended F1 races before a long time ago on the old engines (late 90s), honestly thought they were too bloody loud that it was a distraction to the racing. I know a lot of people loved them and fair enough, I can understand why but when they made the change I was really happy.

  8. I don’t mind what engines specifications they are, just as long as they are all close in performance and the order of the grid is mainly determined by aerodynamic performance, as it was from 2009-2013. I don’t like how certain teams are limited by factors outside of their control, while others benefit from someone else’s good work. Since there are only four engine manufacturers and ten teams, you will always get the situation where a team’s performance is not only dependent on how they perform, but what their engine manufacturer does. And it can get political as well, as works teams such as Ferrari and Mercedes can choose exactly who they want to supply. It seems too convenient, doesn’t it that they are unwilling to supply teams who potentially have the ability to challenge them, but are more than willing to supply team who will never pose a threat to them. The order of the 2018 grid would likely be different if everyone had near equal engines. I would expect Haas, Force India, and Sauber to be pegged back by the likes of Toro-Rosso, Renault and McLaren.

    1. @mashiat

      and the order of the grid is mainly determined by aerodynamic performance

      But, as we saw in 2010-2013, you then get the one team that has over-invested in aero development, even going as far as locking down unique manufacturing techniques under IP law, running away with it – some teams with deep pockets can catch up but the minnows are sunk because they can’t even hope to invest in the wind tunnels & CFD.

      The benefits of an engine formula basically mean that whoever uses the best engines *should* at least be in the place to challenge. Maybe commercial & political dealings have munted that, but that’s really a different problem to do with governance of the sport.

      1. @optimaximal But a formula that is aero-dominant gives smaller teams a bigger chance of an upset. This is because if they can devise some creative solution, they can be propelled up the field, while with this engine-formula dominated F1, you could be creative in the aero side, but you can’t do anything with the engine, as that is something that is just given to you by somebody else.

  9. Most teams are powered by Mercedes engines with Ferrari a close second. They have a lot of pull. Why change the engine formula and cause Mercedes and Ferrari to lose those customers? Simple as that. This road relevent thing is just marketing to the F1 management.
    Once Honda or Renault becomes superior to Mercedes and Ferrari, or Mercedes slips up, i think the status quo remains. The technology keeps competitors out and protects market share.

    1. Hi Johns… I’m confused by your comment… There are ten teams. For “most” to have Merc. engines would mean more than half have to be powered by Merc. – let’s say, six or seven… For Ferrari to be a “close” second they would presumably be powering five or six teams… Do you see the problem… and that’s without mentioning Renault and Honda power… ;-)

  10. My favourite topic! Let’s dive right in.

    It is no wonder the proposed engine rule changes for 2021 did not take off. They were written to be horrible on purpose. The worst kind of compromise to make these new engine rules undesirable for both old and new engine manufacturers. Same road relevant nonsense that is massively expensive while also lets ferrari and mercedes keep their competitive advantage. Ferrari stalled long enough so porsche lost interest. Aston martin pretended it was part of it. Some others did not even want to be known to have been there. Porsche saw what was going on and noped out of it quicker than you can say “road relevant”. Sensibly. No point spending billion dollars with honda results.

    What f1 needs is engine that is 100kg lighter, less powerful (30 second 1000 peak bhp fuel flow limited engine does not make the racing better), much much cheaper, much less computer reliant, and simpler. That kind of engine is the only way to fix the other issue in f1, the massive downforce levels. Comparing to 2014 we now have twice as much downforce. Probably more. That kind of dirty air can not be fixed. There are no magic tricks. Over 60% of the downforce is already ground effects. That is not a solution. Only solution is to reduce downforce by 30-50%. But with less downforce the lap time becomes slower. That’s why lighter engines are crucial. The lighter the engine the less dead weight the cars have to carry. 100kg of weight in f1 add 3 to 4 seconds to lap time. If you take 30% of the downforce away and make the engine 100kg lighter you are still pretty close to the current lap times but the teams are much closer and the cars can follow closer.

    Current engines are 100kg heavier than the v8s for example: 2013 engine rules limited engine weight to 95kg+5kg. The new hybrids are limited to 145kg for the engine plus 20kg to 25kg for the batteries. Total of 100 kg vs 165kg. And that 100kg for the 2013 v8 includes a 25kg kers. Those numbers don’t include things like radiators. Hybrid engine needs bigger radiators so that too makes the hybrid engines heavier.

    That’s the fia rules. Let’s look at other source for the engine weights:

    Racecar engineering 2013 engines special issue, page 11. Direct quote from renault:
    ‘From that stage, one of the key areas we needed to investigate was the packaging of the power unit. The current V8 is 95kg, or 100kg if you add the weight of the MGU. This increases to 120kg when you include the ancillary parts, such as the radiators and other cooling devices. With the 2014 power unit, the V6 turbocharged engine will be a minimum of 145kg, plus 35kg for the battery.

    At 180kg, this is a 80 per cent increase over the current units, plus a further 20kg for the ancillaries such as the intercooler and other radiators.’ The additional weight is partly compensated for by an increase in the minimum weight of the overall vehicle to 685kg“

    In other words v8 engine can be had with 100kg. Hybrid is 200kg. Worst thing is that the electric bits in the current hybrid engines don’t even pay back their own weight in lap time compared to just having more powerful engines. I can calculate that too by comparing a race engine and an f1 hybrid engine:

    Some numbers:
    engine thermal efficiency: 30% (really low number)
    fuel energy per kg: 50 MJ/kg (low number again but let’s try help the hybrids)
    weight of the electric (mgu-k + mgu-h) = 50kg (optimistic as the battery alone is 35kg, source 2013 racecar engineering, page 10)
    continuous electric output in a f1 per lap= 4MJ (optimistic)

    Amount of energy we can get from the electrics for 50kg of weight in 60 lap race = 4MJ * 60 = 240MJ
    Amount of energy we can get from 50kg of fuel = 50 MJ/kg * 0,30 * 50 = 750MJ (more energy from fuel)

    =Hybrid is worse.

    And then we have fuel saving at all time high. This statement comes from paddy lowe:
    https://www.eurosport.com/formula-1/mercedes-working-on-dramatically-louder-f1-engine_sto5453464/story.shtml
    While people complain about drivers having to fuel save in the race and so on, we’ve always had to fuel save because it’s never optimal to drive flatout and the degree to which we have to save fuel in the race is not excessive in my view. It’s just mildly more than it used to be

    1. @socksolid, congratulations, rare to get a comment with logic, numbers (as yet unchallenged) and reference to source material, I envy your diligence.

      1. Ditto

    2. Solid points, @socksolid.

      One benefit from the hybrid system is the ability to map the electric motor to fill gaps in the petrol motor torque curve. Which when mapped well provides better driveability. Can’t argue with the energy output of current generation batteries – much lower energy density than burning dead dinosaur bits.

      But the weight and length of this generation of single seat limos make them appear brutally awkward on slow corners. The extra weight and length is required for the hybrid power units and happily for aero-buffs more downforce options.

      The 2017 aero rules were a knee-jerk Bernie reaction – going for lap records to improve the ‘show’ and make the old F1 used car more attractive to Liberty.

      Would be happier to see 100-150kg lighter cars with 30-50% less aero. Nimble, fast with closer racing beats dirty air limo DRS cruising. If it means dumping the hybrid parts until a lighter more powerful storage solution is implemented, like aluminum-air batteries, then I would vote for your dead-dino-power only option.

  11. That’s good, I think that the current engine are impressive and I would like to see manufacturer push the hybrid and electric technology further rather than going back to simpler engines.

    Maybe, many problems of F1 (besides areo) can be solved by gradually limiting the communication between driver and pit wall during the race. In this way the skill of the pilot alone would be much more important, and the race would be a real chess match between pilots (instead than between pit walls and engineers).

    This way, the engineers would be forced to develop an engine that is sophisticated enough to extract maximum potential, but simple enough to be controlled by the driver and the driver only.

    (same thing for tires, let the driver manage the race, and we will see its real skills)

    1. Maybe, many problems of F1 (besides areo) can be solved by gradually limiting the communication between driver and pit wall during the race.

      Bernie, is that you?

  12. @keithcollantine,@dieterrencken, please stop repeating the erroneous “fact” that turbochargers generate heat, the heat only comes from combustion of fuel in the combustion chamber and the hot gas generated drives the pistons first by massive expansion and then secondly spins the turbine in the turbocharger, any increase in heat after the gasses exhaust the combustion chamber are an inefficient by-product caused either by incomplete combustion in the chamber or friction in the turbo both of which are to be avoided as much as possible.

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