5.2L Supercharged V8 Confirmed

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Tx State

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I see some yes but you can find engine failure in all vehicles. Some engine failures here and there doesn't mean every 5.2 ever made is going to grenade.
 

NASSTY

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I see some yes but you can find engine failure in all vehicles. Some engine failures here and there doesn't mean every 5.2 ever made is going to grenade.
Same goes for the 3.5 Ecoboost. Sasquatch's pupose in life is to convince people that all 3.5 Ecoboosts are going to grenade.
 

mezger

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I see some yes but you can find engine failure in all vehicles. Some engine failures here and there doesn't mean every 5.2 ever made is going to grenade.
Yep. Just about every cool car I've owned or am considering owning has some kind of mega $$$$ gremlin. LS7 ingests exhaust valves, 997 Porsche turbos need their coolant pipes pinned, the S65 eats rod bearings and throttle actuators, early LS engines had piston slap, lesser Porsches had IMS issues, N54s had long time issues with HPFPs, e46s were prone to subframe mounts tearing, C63s have headbolt and camshaft issues, apparently, changing the glow plugs on my dirtymax is roulette... etc. etc. :yawn:

Doesn't stop me from enjoying the hell out of them.
 

smurfslayer

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I see some yes but you can find engine failure in all vehicles. Some engine failures here and there doesn't mean every 5.2 ever made is going to grenade.

kiddie molester is really sasquatch77, and has been trolling here with some of the admins at least tacit approval since the ecoboost was created. She has been banned several times as sasquatch77, sasquatch78, mcnawsty, mgd, gargamel, gargamel. and smurfslayer. (note the trailing period). Her main function in life is not known, but, she has enormous free time to troll here on FRF.

I suspect mental illness at play here, but you can research their postings for yourself. trolling, falsehoods and clickbait are the traits of old ignoramus. it started out as trying to convince users to drill holes in their intercooler, and just went downhill from there. it’s best just to report her postings as troll posts using the “report” feature.
 

rtmozingo

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If you get into boost- yeah sure the S/C engine drinks the fuel, but again, same thing with the TTV6. 8 to 10 MPG all day long in boost. Yes, turbos ARE more efficient, no doubt. If you want max off road mileage, yes a TT V6 will beat out a S/C V8. Physics are physics though, and in the end the total efficiency of the two engines vs amount of energy available in the fuel will be way more similar than different.

this is a contradictory statement. Either turbos are more efficient or they are not. Spoiler alert: they are. Superchargers draw more energy from the engine, and still exhaust unused energy - you never see people getting better fuel mileage after adding a supercharger. You do, however see increases in power and fuel efficiency when adding a turbo. Why? Because you are reclaiming the unused energy in the exhaust gasses. Meanwhile the supercharger makes the engine less efficient, especially at lower power.

Engineering explained always does a good job explaining these sorts of things. This is a basic article, but should serve as a starting point for those less familiar with the tech: https://www.carthrottle.com/post/en...s-and-cons-of-turbochargers-vs-superchargers/
And here is the video:

@mezger I've not yet been able to read it yet, but perhaps this is what you are looking for? All I can say with certainty is that the net result is a more efficient system. Yes, you have assorted losses, but again, this is all made up for by the exhaust energy, which is lost outside of turbocharger use. Say (making up numbers here) 30% of the engine power is lost to exhaust - yes, you may have backpressure, as well as heat losses, etc, but even if the turbo cycle itself is only 50% efficient, the vehicle itself is now 15% more efficient than it was. Make sense?

Meanwhile, throw a supercharged on the engine, and the engine was to work harder to product the same power, and therefore becomes LESS efficient. You still lose 30% as exhaust gas, but now have a 5% draw on the engine at all RPM. It is weird because the engine is producing more power, so you'd think it is more efficient, but that's actually the opposite of what is happening. It gets complicated when you consider air/fuel mixtures, which I think may be what @EricM was alluding to earlier.

Edit: A quote from wikipedia on superchargers:
Roots blowers tend to be only 40–50% efficient at high boost levels; by contrast centrifugal (dynamic) superchargers are 70–85% efficient at high boost. Lysholm-style blowers can be nearly as efficient as their centrifugal counterparts over a narrow range of load/speed/boost, for which the system must be specifically designed.

Mechanically driven superchargers may absorb as much as a third of the total crankshaft power of the engine and are less efficient than turbochargers. However, in applications for which engine response and power are more important than other considerations, such as top-fuel dragsters and vehicles used in tractor pulling competitions, mechanically driven superchargers are very common.

The thermal efficiency, or fraction of the fuel/air energy that is converted to output power, is less with a mechanically driven supercharger than with a turbocharger, because turbochargers use energy from the exhaust gas that would normally be wasted. For this reason, both economy and the power of a turbocharged engine are usually better than with superchargers.

Turbochargers suffer (to a greater or lesser extent) from so-called turbo-spool (turbo lag; more correctly, boost lag), in which initial acceleration from low RPM is limited by the lack of sufficient exhaust gas mass flow (pressure). Once engine RPM is sufficient to raise the turbine RPM into its designed operating range, there is a rapid increase in power, as higher turbo boost causes more exhaust gas production, which spins the turbo yet faster, leading to a belated "surge" of acceleration. This makes the maintenance of smoothly increasing RPM far harder with turbochargers than with engine-driven superchargers, which apply boost in direct proportion to the engine RPM. The main advantage of an engine with a mechanically driven supercharger is better throttle response, as well as the ability to reach full-boost pressure instantaneously. With the latest turbocharging technology and direct gasoline injection, throttle response on turbocharged cars is nearly as good as with mechanically powered superchargers, but the existing lag time is still considered a major drawback, especially considering that the vast majority of mechanically driven superchargers are now driven off clutched pulleys, much like an air compressor.

Turbocharging has been more popular than superchargers among auto manufacturers owing to better power and efficiency. For instance Mercedes-Benz and Mercedes-AMG previously had supercharged "Kompressor" offerings in the early 2000s such as the C230K, C32 AMG, and S55 AMG, but they have abandoned that technology in favor of turbocharged engines released around 2010 such as the C250 and S65 AMG biturbo. However, Audi did introduce its 3.0 TFSI supercharged V6 in 2009 for its A6, S4, and Q7, while Jaguar has its supercharged V8 engine available as a performance option in the XJ, XF, XKR, and F-Type, and, via joint ownership by Tata motors, in the Range Rover also.
 
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rtmozingo

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More from wikipedia:


Turbocharging[edit]
Main article: Turbocharger
A mechanically driven supercharger has to take its drive power from the engine. Taking a single-stage single-speed supercharged engine, such as an early Rolls-Royce Merlin, for instance, the supercharger uses up about 150 hp (110 kW). Without a supercharger, the engine could produce about 750 horsepower (560 kilowatts), but with a supercharger, it produces about 1,000 hp (750 kW)—an increase of about 400 hp (750 - 150 + 400 = 1000 hp), or a net gain of 250 hp (190 kW). This is where the principal disadvantage of a supercharger becomes apparent. The engine has to burn extra fuel to provide power to drive the supercharger. The increased air density during the input cycle increases the specific power of the engine and its power-to-weight ratio, but at the cost of an increase in the specific fuel consumption of the engine. In addition to increasing the cost of running the aircraft a supercharger has the potential to reduce its overall range for a specific fuel load.

As opposed to a supercharger driven by the engine itself, a turbocharger is driven using the otherwise wasted exhaust gas from the engine. The amount of power in the gas is proportional to the difference between the exhaust pressure and air pressure, and this difference increases with altitude, helping a turbocharged engine to compensate for changing altitude. This increases the height at which maximum power output of the engine is attained compared to supercharger boosting, and allows better fuel consumption at high altitude compared to an equivalent supercharged engine. This facilitates increased true airspeed at high altitude and gives a greater operational range than an equivalently boosted engine using a supercharger.

The majority of aircraft engines used during World War II used mechanically driven superchargers, because they had some significant manufacturing advantages over turbochargers. However, the benefit to operational range was given a much higher priority to American aircraft because of a less predictable requirement on operational range, and having to travel far from their home bases. Consequently, turbochargers were mainly employed in American aircraft engines such as the Allison V-1710 and the Pratt & Whitney R-2800, which were comparably heavier when turbocharged, and required additional ducting of expensive high-temperature metal alloys in the gas turbine and preturbine section of the exhaust system. The size of the ducting alone was a serious design consideration. For example, both the F4U Corsair and the P-47 Thunderbolt used the same radial engine, but the large barrel-shaped fuselage of the turbocharged P-47 was needed because of the amount of ducting to and from the turbocharger in the rear of the aircraft. The F4U used a two-stage intercooled supercharger with more compact layout. Nonetheless, turbochargers were useful in high-altitude bombers and some fighter aircraft due to the increased high altitude performance and range.

Turbocharged piston engines are also subject to many of the same operating restrictions as those of gas turbine engines. Turbocharged engines also require frequent inspections of their turbochargers and exhaust systems to search for possible damage caused by the extreme heat and pressure of the turbochargers. Such damage was a prominent problem in the early models of the American Boeing B-29 Superfortresshigh-altitude bombers used in the Pacific Theater of Operations during 1944–45.

Turbocharged piston engines continued to be used in a large number of postwar airplanes, such as the B-50 Superfortress, the KC-97 Stratofreighter, the Boeing Stratoliner, the Lockheed Constellation, and the C-124 Globemaster II.

In more recent times most aircraft engines for general aviation (light airplanes) are naturally aspirated, but the smaller number of modern aviation piston engines designed to run at high altitudes use turbocharger or turbo-normalizer systems, instead of a supercharger driven from the crank shafts. The change in thinking is largely due to economics. Aviation gasoline was once plentiful and cheap, favoring the simple but fuel-hungry supercharger. As the cost of fuel has increased, the ordinary supercharger has fallen out of favor. Also, depending on what monetary inflation factor one uses, fuel costs have not decreased as fast as production and maintenance costs have.

Effects of fuel octane rating[edit]
Until the late 1920s all automobile and aviation fuel was generally rated at 87 octane or less. This is the rating that was achieved by the simple distillation of "light crude" oil. Engines from around the world were designed to work with this grade of fuel, which set a limit to the amount of boosting that could be provided by the supercharger, while maintaining a reasonable compression ratio.

Octane rating boosting through additives was a line of research being explored at the time. Using these techniques, less valuable crude could still supply large amounts of useful gasoline, which made it a valuable economic process. However, the additives were not limited to making poor-quality oil into 87-octane gasoline; the same additives could also be used to boost the gasoline to much higher octane ratings.

Higher-octane fuel resists auto ignition and detonation better than does low-octane fuel. As a result, the amount of boost supplied by the superchargers could be increased, resulting in an increase in engine output. The development of 100-octane aviation fuel, pioneered in the USA before the war, enabled the use of higher boost pressures to be used on high-performance aviation engines, and was used to develop extremely high-power outputs – for short periods – in several of the pre-war speed record airplanes. Operational use of the new fuel during World War II began in early 1940 when 100-octane fuel was delivered to the British Royal Air Force from refineries in America and the East Indies.[19] The German Luftwaffe also had supplies of a similar fuel.[20][21]

Increasing the knocking limits of existing aviation fuels became a major focus of aero engine development during World War II. By the end of the war, fuel was being delivered at a nominal 150-octane rating, on which late-war aero engines like the Rolls-Royce Merlin 66[22][23] or the Daimler-Benz DB 605DC developed as much as 2,000 hp (1,500 kW).[24][25]


The last part about octane rating is why the manual recommends 93, and why you won't get peak power without it.
 

SilverBolt

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this is a contradictory statement. Either turbos are more efficient or they are not. Spoiler alert: they are. Superchargers draw more energy from the engine, and still exhaust unused energy - you never see people getting better fuel mileage after adding a supercharger. You do, however see increases in power and fuel efficiency when adding a turbo. Why? Because you are reclaiming the unused energy in the exhaust gasses. Meanwhile the supercharger makes the engine less efficient, especially at lower power.

Engineering explained always does a good job explaining these sorts of things. This is a basic article, but should serve as a starting point for those less familiar with the tech: https://www.carthrottle.com/post/en...s-and-cons-of-turbochargers-vs-superchargers/
And here is the video:

@mezger I've not yet been able to read it yet, but perhaps this is what you are looking for? All I can say with certainty is that the net result is a more efficient system. Yes, you have assorted losses, but again, this is all made up for by the exhaust energy, which is lost outside of turbocharger use. Say (making up numbers here) 30% of the engine power is lost to exhaust - yes, you may have backpressure, as well as heat losses, etc, but even if the turbo cycle itself is only 50% efficient, the vehicle itself is now 15% more efficient than it was. Make sense?

Meanwhile, throw a supercharged on the engine, and the engine was to work harder to product the same power, and therefore becomes LESS efficient. You still lose 30% as exhaust gas, but now have a 5% draw on the engine at all RPM. It is weird because the engine is producing more power, so you'd think it is more efficient, but that's actually the opposite of what is happening. It gets complicated when you consider air/fuel mixtures, which I think may be what @EricM was alluding to earlier.

Edit: A quote from wikipedia on superchargers:
Increased fuel efficiency when adding a turbo???? On what planet? Here on earth when more air is introduced into the combustion chamber you must increase the amount of fuel as well. The more boost, the more fuel. Yes, turbos are more efficient than superchargers but both will cost you MPG's.
 
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