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Are turbocharging and supercharging good for US

DGS49

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Turbocharging and supercharging are ways that an ICE can '"pretend" that it is bigger than it is. A 2 liter engine can act like a 4 liter engine by forcing air-fuel mixture into the cylinders (rather than allowing it to get into the cylinders under merely atmospheric pressure), thus creating a bigger "bang." In fact, there is almost no limit to the effect. Some manufacturers are producing 2-liter engines getting almost 400HP by either turbocharging (Porsche) or a combination of turbo and supercharging (Volvo).

The advantage of those two strategies is that when you are not "pushing" the car, it acts like the smaller displacement engine, thus getting better fuel economy than a larger displacement engine of the same power. Hence, on the EPA's fuel economy cycle, where the car is driven like a Granny would drive, it gets "good" gas mileage - better than the larger displacement engine of the same HP.

But there are also disadvantages that are rarely discussed. Charged engines are more complex, get hotter, and are subject to much higher stresses, and must include coolers for not only the engine block but also the turbocharger itself. The long term viability of these high-performance turbos (when compared to larger-displacement "regular" engines) is still undetermined.

It is a disputed matter whether turbocharged engines actually do get better mileage than larger engines of the same power. Some say that the "base" power in a turbo is so pathetic that the driver unconsciously pushes the car all the time, just to get the performance of the larger engine. The only time when it is clearly beneficial is on the highway at constant speeds - which could be overcome by higher gearing with a larger engine.

But are turbocharged engines cheaper to manufacture than larger-displacement engines of the same power? How could they be? The incremental cost of adding displacement is minimal.

I think the turbo craze is just manufacturers using this strategy to make their fuel economy look better than it actually is (due to the EPA testing protocol), at the expense of REAL fuel economy and longevity.

But what do I know?
 
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DGS49

DGS49

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But having said that, my wife's 3-series, with its turbo-4 and 8-speed trans is incredible. It is smooth, powerful, and has achieved almost 26mpg, combined over 40,000 miles, with very little highway mileage. And we always use 89-octane, rather than high test, as recommended.

Will it last? I will never find out. As SOON as the CPO warranty expires at 75k, that car is GONE.
 

Andylusion

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Turbocharging and supercharging are ways that an ICE can '"pretend" that it is bigger than it is. A 2 liter engine can act like a 4 liter engine by forcing air-fuel mixture into the cylinders (rather than allowing it to get into the cylinders under merely atmospheric pressure), thus creating a bigger "bang." In fact, there is almost no limit to the effect. Some manufacturers are producing 2-liter engines getting almost 400HP by either turbocharging (Porsche) or a combination of turbo and supercharging (Volvo).

The advantage of those two strategies is that when you are not "pushing" the car, it acts like the smaller displacement engine, thus getting better fuel economy than a larger displacement engine of the same power. Hence, on the EPA's fuel economy cycle, where the car is driven like a Granny would drive, it gets "good" gas mileage - better than the larger displacement engine of the same HP.

But there are also disadvantages that are rarely discussed. Charged engines are more complex, get hotter, and are subject to much higher stresses, and must include coolers for not only the engine block but also the turbocharger itself. The long term viability of these high-performance turbos (when compared to larger-displacement "regular" engines) is still undetermined.

It is a disputed matter whether turbocharged engines actually do get better mileage than larger engines of the same power. Some say that the "base" power in a turbo is so pathetic that the driver unconsciously pushes the car all the time, just to get the performance of the larger engine. The only time when it is clearly beneficial is on the highway at constant speeds - which could be overcome by higher gearing with a larger engine.

But are turbocharged engines cheaper to manufacture than larger-displacement engines of the same power? How could they be? The incremental cost of adding displacement is minimal.

I think the turbo craze is just manufacturers using this strategy to make their fuel economy look better than it actually is (due to the EPA testing protocol), at the expense of REAL fuel economy and longevity.

But what do I know?
It depends greatly on the quality of the engine being blown, and the quality of the blower.

In general, you can easily blow a smaller engine until can out perform much larger engines. The savings is in the weight. While the cost is incremental, the weight is not. Larger displacement, requires lots of metal, and metal is heavy.

You can also fit more power, into a smaller frame. The larger the frame of the car, equals more weight, and more drag.

Then of course you can mitigate all of that with aluminum and plastic.

So the end results is very complicated.

Regardless, the real driving factor in this is generally price. Regardless of power / fuel / efficiency ratios, the one factor that is undeniably against blown motors, is simply price.

Blowers cost lots of money. Have to route the exhaust, and keep it shielded, route the intake, and keep is cleaned. Route oil lines to keep it cooled and oiled. You often need to then have cooling for the oil, and oiling for intake air.
And then of course, the cost of the blower or turbo itself, which is expensive.

I've seen good quality turbos, going for a thousand at the low end, and up to four grand, and that's just what I've seen after market.

So typically, you are going to see turbos and blowers on rather price street racing and rally cars. Not on average general public cars. It's just not worth it, unless you are going drifting or racing.
 

Jarlaxle

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Turbocharging and supercharging are ways that an ICE can '"pretend" that it is bigger than it is. A 2 liter engine can act like a 4 liter engine by forcing air-fuel mixture into the cylinders (rather than allowing it to get into the cylinders under merely atmospheric pressure), thus creating a bigger "bang." In fact, there is almost no limit to the effect. Some manufacturers are producing 2-liter engines getting almost 400HP by either turbocharging (Porsche) or a combination of turbo and supercharging (Volvo).

The advantage of those two strategies is that when you are not "pushing" the car, it acts like the smaller displacement engine, thus getting better fuel economy than a larger displacement engine of the same power. Hence, on the EPA's fuel economy cycle, where the car is driven like a Granny would drive, it gets "good" gas mileage - better than the larger displacement engine of the same HP.

But there are also disadvantages that are rarely discussed. Charged engines are more complex, get hotter, and are subject to much higher stresses, and must include coolers for not only the engine block but also the turbocharger itself. The long term viability of these high-performance turbos (when compared to larger-displacement "regular" engines) is still undetermined.

It is a disputed matter whether turbocharged engines actually do get better mileage than larger engines of the same power. Some say that the "base" power in a turbo is so pathetic that the driver unconsciously pushes the car all the time, just to get the performance of the larger engine. The only time when it is clearly beneficial is on the highway at constant speeds - which could be overcome by higher gearing with a larger engine.

But are turbocharged engines cheaper to manufacture than larger-displacement engines of the same power? How could they be? The incremental cost of adding displacement is minimal.

I think the turbo craze is just manufacturers using this strategy to make their fuel economy look better than it actually is (due to the EPA testing protocol), at the expense of REAL fuel economy and longevity.

But what do I know?
Not a damn thing. Turbo engines have been around for 30+ years...they work quite well and are no less durable than a larger-displacement engine if engineered correctly. (Thousands of Volvos wound up 200K on turbo 4-cylinders, and those weren't even water-cooled turbochargers.)
 

Jarlaxle

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Turbocharging and supercharging are ways that an ICE can '"pretend" that it is bigger than it is. A 2 liter engine can act like a 4 liter engine by forcing air-fuel mixture into the cylinders (rather than allowing it to get into the cylinders under merely atmospheric pressure), thus creating a bigger "bang." In fact, there is almost no limit to the effect. Some manufacturers are producing 2-liter engines getting almost 400HP by either turbocharging (Porsche) or a combination of turbo and supercharging (Volvo).

The advantage of those two strategies is that when you are not "pushing" the car, it acts like the smaller displacement engine, thus getting better fuel economy than a larger displacement engine of the same power. Hence, on the EPA's fuel economy cycle, where the car is driven like a Granny would drive, it gets "good" gas mileage - better than the larger displacement engine of the same HP.

But there are also disadvantages that are rarely discussed. Charged engines are more complex, get hotter, and are subject to much higher stresses, and must include coolers for not only the engine block but also the turbocharger itself. The long term viability of these high-performance turbos (when compared to larger-displacement "regular" engines) is still undetermined.

It is a disputed matter whether turbocharged engines actually do get better mileage than larger engines of the same power. Some say that the "base" power in a turbo is so pathetic that the driver unconsciously pushes the car all the time, just to get the performance of the larger engine. The only time when it is clearly beneficial is on the highway at constant speeds - which could be overcome by higher gearing with a larger engine.

But are turbocharged engines cheaper to manufacture than larger-displacement engines of the same power? How could they be? The incremental cost of adding displacement is minimal.

I think the turbo craze is just manufacturers using this strategy to make their fuel economy look better than it actually is (due to the EPA testing protocol), at the expense of REAL fuel economy and longevity.

But what do I know?
It depends greatly on the quality of the engine being blown, and the quality of the blower.

In general, you can easily blow a smaller engine until can out perform much larger engines. The savings is in the weight. While the cost is incremental, the weight is not. Larger displacement, requires lots of metal, and metal is heavy.

You can also fit more power, into a smaller frame. The larger the frame of the car, equals more weight, and more drag.

Then of course you can mitigate all of that with aluminum and plastic.

So the end results is very complicated.

Regardless, the real driving factor in this is generally price. Regardless of power / fuel / efficiency ratios, the one factor that is undeniably against blown motors, is simply price.

Blowers cost lots of money. Have to route the exhaust, and keep it shielded, route the intake, and keep is cleaned. Route oil lines to keep it cooled and oiled. You often need to then have cooling for the oil, and oiling for intake air.
And then of course, the cost of the blower or turbo itself, which is expensive.

I've seen good quality turbos, going for a thousand at the low end, and up to four grand, and that's just what I've seen after market.

So typically, you are going to see turbos and blowers on rather price street racing and rally cars. Not on average general public cars. It's just not worth it, unless you are going drifting or racing.
You have absolutely no idea what you are blathering about.
 

Shawnee_b

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It's for those who want it. My Vette has an LS6. High comp, hot cam. 405 hp. If I stay out of the pedal I can still average 22-25 and usually do.
 

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