2011-2012 Mustang GT Twin turbo system...

[Truck Norris]

Lets try not to turn this thread into a Supercharger vs Turbo thread.

But I just have to add my two cents

Ford and Chevy have far more turbo charged vehicles on the road then supercharged ones so that should answer your question as what is better. I'm guessing its a lot cheaper for companies bolt a TVS supercharger on top of a performance V8's vs going the turbo route which is more costly and is more prone to warranty work (think Audi S4's). But this past year quite a few supercharged vehicles got turbos and my main guess is due to increased fuel economy and power/ efficiency (AMG and BMW have more then a few new turbo engines this past year) and the Cobalt SS/TC is far better then the SS/SC.

[scrming]

Originally Posted by Truck Norris

Lets try not to turn this thread into a Supercharger vs Turbo thread.

But I just have to add my two cents

Ford and Chevy have far more turbo charged vehicles on the road then supercharged ones so that should answer your question as what is better. I'm guessing its a lot cheaper for companies bolt a TVS supercharger on top of a performance V8's vs going the turbo route which is more costly and is more prone to warranty work (think Audi S4's). But this past year quite a few supercharged vehicles got turbos and my main guess is due to increased fuel economy and power/ efficiency (AMG and BMW have more then a few new turbo engines this past year) and the Cobalt SS/TC is far better then the SS/SC.

And look how the Ford EcoBoost is showing up in so many different vehicles... I forget the exact percentages and time line, but Ford is definitely pushing forward with their turbos!

[JamesNoBrakes]

He's answered his own question though, the ZR1 is a lot cheaper than a ferarri or other super-high end vehicle that it can "out perform", although when we are thinking about this, are we talking about in "every catagory" or just 1/4 mile or something? More expensive cars may end up more well-rounded, more luxurious, etc. That doesn't mean the ZR1 is a bad car of course. Some of the other sacrifices you make for the "cheaper" SC system deal with fuel consumption, engine longevity/pressure, most likely weight, heat dissapation, etc. The SC may suffer more from heat soak when pushed hard on a track, whereas airflow with a turbo system may keep it cooler (and require more engineering to do so). SC systems are generaly simpler and more cost effective for the manufacturer I think, and they don't really care that it might mean more money spent for gas, more internal engine pressure, heatsoak, etc. Just look at a turbo system, the tubing bends and so on, and then a comparable SC system.

The manufacturers are interested in turning a profit, and they are NOT putting out a bad product if they are making a SC car, but if you want something better or more "rounded" in terms of performance, most higher end cars have turbos. I think when "money becomes no object" (or at least not the primary) the "can achieve more with less boost" aspect of turbos makes them the primary choice.

As far as power or torque under the curve, go back to what I was saying about the turbo size and tune, generalities are poor in this case and compressed air and fuel creates a LOT of torque.

[rez333]

I found this information on the net which answers all my questions (finally!):

Cost
The cost of supercharger and a turbocharger systems for the same engine are approximately the same, so cost is generally not a factor.

Lag
This is perhaps the biggest advantage that the supercharger enjoys over the tubo. Because a turbocharger is driven by exhaust gasses, the turbocharger's turbine must first spool up before it even begins to turn the compressor's impeller. This results in lag time which is the time needed for the turbine to reach its full throttle from an intermediate rotational speed state. During this lag time, the turbocharger is creating little to no boost, which means little to no power gains during this time. Smaller turbos spool up quicker, which eliminates some of this lag. Turbochargers thus utilize a wastegate, which allows the use of a smaller turbocharger to reduce lag while preventing it from spinning too quickly at high engine speeds. The wastegate is a valve that allows the exhaust to bypass the turbine blades. The wastegate senses boost pressure, and if it gets too high, it could be an indicator that the turbine is spinning too quickly, so the wastegate bypasses some of the exhaust around the turbine blades, allowing the blades to slow down..
A Supercharger, on the other hand, is connected directly to the crank, so there is no "lag". Superchargers are able to produce boost at a very low rpm, especially screw-type and roots type blowers.

Efficiency
This is the turbo's biggest advantage. The turbocharger is generally more economical to operate as it as it is driven primarily by potential energy in the exhaust gasses that would otherwise be lost out the exhaust, whereas a supercharger draws power from the crank, which can be used to turn the wheels. The turbocharger's impeller is also powered only under boost conditions, so there is less parasitic drag while the impeller is not spinning. The turbocharger, however, is not free of inefficiency as it does create additional exhaust backpressure and exhaust flow interruption.

Heat
Because the turbocharger is mounted to the exhaust manifold (which is very hot), turbocharger boost is subject to additional heating via the turbo's hot casing. Because hot air expands (the opposite goal of a turbo or supercharger), an intercooler becomes necessary on almost all turbocharged applications to cool the air charge before it is released into the engine. This increases the complexity of the installation. A centrifugal supercharger on the other hand creates a cooler air discharge, so an intercooler is often not necessary at boost levels below 10psi. That said, some superchargers (especially roots-type superchargers) create hotter discharge temperatures, which also make an intecooler necessary even on fairly low-boost applications.

Surge
Because a turbocharger first spools up before the boost is delivered to the engine, there is a surge of power that is delivered immediately when the wastegate opens (around 3000 rpm). This surge can be damaging to the engine and drivetrain, and can make the vehicle difficult to drive or lose traction.

Back Pressure
Because the supercharger eliminates the need to deal with the exhaust gas interruption created by inserting a turbocharger turbine into the exhaust flow, the supercharger creates no additional exhaust backpressure. The amount of power that is lost by a turbo's turbine reduces it's overall efficiency.

Noise
The turbocharger is generally quiter than the supercharger. Because the turbo's turbine is in the exhaust, the turbo can substantially reduce exhaust noise, making the engine run quieter. Some centrifugal superchargers are known to be noisy and whistley which, annoys some drivers or makes some very happy!

Reliability
In general, superchargers enjoy a substantial reliability advantage over the turbocharger. When a a turbo is shut off (i.e. when the engine is turned off), residual oil inside the turbo's bearings can be baked by stored engine heat. This, combined with the turbo's extremely high rpms (up to 150,000rpm) can cause problems with the turbo's internal bearings and can shorten the life of the turbocharger. In addition, many turbos require aftermarket exhaust manifolds, which are often far less reliable than stock manifolds.

Ease of Installation
Superchargers are substantially easier to install than a turbos because they have far fewer components and simpler devices. Turbos are complex and require manifold and exhaust modifications, intercoolers, extra oil lines, etc. - most of which is not needed with most superchargers. A novice home mechanic can easily install most supercharger systems, while a turbo installation should be left to a turbo expert.

Maximum Power Output
Turbos are known for their unique ability to spin to incredibly high rpms and make outrages peak boost figures (25psi+). While operating a turbocharger at very high levels of boost requires major modifications to the rest of the engine, the turbo is capable of producing more peak power than superchargers.

Tunability
Turbochargers, because they are so complex and rely on exhaust pressure, are notoriously difficult to tune. Superchargers, on the other hand, require few fuel and ignition upgrades and normally require little or no engine tuning.

And a response:

Allow me to parlay some of my knowledge then.

Cost: Brand new, yes a turbo kit and a supercharger kit will cost the same(ish. Turbos will probably be a few hundred cheaper becase there is more demand for them. Also don't forget about labor). If you have the knowlegde to build a junkyard turbo setup, then it will be much cheaper to go that route. If not, it all depends on what deals you find.

Lag: Lag is only a problem when you have a huge turbo and a tiny engine. A turbo that is sized for a small displacement engine should not suffer from any lag. A good, street-designed turbo kit should not have any turbo lag. Avoid kits that advertise "drag racing, huge power, high-boost, etc." Those will have big turbos and big lag.

Efficiency: If every turbo was built the same as Garrett's Disco Potato, this wouldn't be a problem. Sadly, most turbos were last redesigned in the 1970s. If you want to know more about the Disco Potato turbo, I can tell you, but that is mostly a Nissan Silvia turbo. And rather expensive.

Heat: Compressing air heats it up, so both types of compressors will heat the air coming into the engine. However, because a supercharger is less efficient it will actually heat the air more than a turbo. Many SC kits actually have a tiny air to water intercooler sandwiched between the compressor and the intake manifold. This only holds true for a Roots SC (commonly seen on Top Fuel dragsters). A centrifugal SC can use a standard air-to-air intercooler like a turbo, because it compresses air more like a turbo (and can be mounted anywhere in the engine bay). However most Honda SC kits I have seen use Roots-type superchargers, which are also prone to heat soak. So they will lose power as they heat up. Also rememer that SCs tend to run lower boost than turbos. Typical SC kits run about 7 psi. Typical turbos run about 8 or 9 psi. Suffice it to say that turbos will run cooler pound for pound. Also, you may need to upgrade your cooling system, no matter which route you take.

Surge: True if you have a late-spooling turbo. However, if you keep out of the boost, you can actually drive around town like your car has no compressor at all, saving gas mileage. That's not possible with an SC.

Back pressure: Both types of blowers will benefit from a bigger exhaust. However, the turbo will make better use of that flow because it can suck air out faster. Think about it like this: what's easier, pushing a column through a hole, or pulling it out? Turbos pull, SCs push.

Noise: BOVs can be very loud. But it's a cool sound. And again, if you keep out of the boost, you won't hear it. My Silvia has a 3.5" exhaust, and a fat turbo, but the loudest part of the car is the blow-off valve. Around town, the car is actually quite civilized.

Reliability: Both compressors will reduce the life of your engine. Simply put, it wasn't meant to take it. The oil bit is true, but only if you drive like an idiot and immediately shut off the car. If you've been racing, then allow a brief cool-down period (five minutes or so idling, or about ten minutes of sane driving). On the street, oil-clumping should be a non-issue. Also, if you run your turbo within it's design limits, then it will be fine (ie no overspinning. Turbos can over-rev too) Any off-the-shelf kit will already have this worked out. But like any part turbos (and SCs) will wear out. As for the manifolds, most turbo kits use cast-iron exhaust manifolds, which are very strong. Tubular manifolds, seen on race cars, are weaker and less reliable, but only in cars where there is a lot of heat. You won't need the extra flow offered by the tubular manifold unless you are doing some hardcore racing.

Installation: This is pretty much correct.

Power output: Also corect. This is because at a certain point, the SC takes away more power than it actually produces. There is a plateau where turning up the boost on an SC causes a power loss, because the engine can't overcome the drag losses caused by the SC. Also, changing the boost on an SC means changing the drive pulley. On a turbo, it's a simple push of the button or a turn of the screw (if you have an external wastegate).

Tuning: This is only true if you have a muscle car. Most import tuners are much more familiar with turbos and can tune them fine. And with the invention of electronic boost controllers, boost spikes are a thing of the past. Computers have made turbos the compressor of the future. Changing the the boost is a matter of telling the computer to change the ignition timing, add more fuel, and turn up the boost. Any competent tuner can do that in about 5 minutes. To do the same with an SC means replacing the boost pulley and then retuning. That's at least 30 minutes.

A low boost turbo in the long run will probably be your best bet since more people are familiar with the mechanics behind them. Plus parts will be a bit easier to get (if you blow a turbo, you can probably replace it with something from a Mitsubishi Eclipse). Also, the BOV will make that cool sneeze everyone loves and a grinning intercooler just looks freaking cool.

My one question is, why do you want to add more power? Just because? With today's gas prices, your money may be better spent on some bolt-on parts, which when combined well can give you about 30 hp and a very nice sounding car. Plus the reliability will be much higher and the initial cost will be lower. Plus it will be easier to inspect the car (assuming you have to pass an emissions test where you live).

[rez333]

Originally Posted by scrming

And look how the Ford EcoBoost is showing up in so many different vehicles... I forget the exact percentages and time line, but Ford is definitely pushing forward with their turbos!

I said PERFORMANCE CARS. All American PERFORMANCE CARS use the SC. American passenger cars/trucks may use turbo, but who cares.

[motorhead]

Originally Posted by motorhead

So, how long does it take to blow the bottom end out of the 5.0 with that set up and I don't mean just driving it around town to the store?

So where's the answer to my question. This turbo vs supercharger argument is as old as superchargers and turbos themselves. They each have their place in certain applications.

I want to know how long until this thing Blows it's cookies with a stock bottom end.

[scrming]

Originally Posted by rez333

I said PERFORMANCE CARS. All American PERFORMANCE CARS use the SC. American passenger cars/trucks may use turbo, but who cares.

[rez333]

@scrming: the point in me saying that American PERFORMANCE CARS all use SC, was not to imply by that statement that that automatically makes SC superior to Turbo. Therefore your video is pointless.

The point is that when choosing one of the two (SC vs Turbo), the engineers chose a SC for their top end versions of the performance/sports cars for a reason. Given that whether it's an all-out sports car (ZR1) or competing pony cars (ZL1 and GT500) - the solution that Chevy/Ford used was "Supercharger" - what was the reason? More importantly, why do Europeans predominantly use Turbo? As far as I know, only Mercedes Benz choose Superchargers for their top-end performance cars?

Anyway, I think I answered the question by posting the information above - that has answered it for me.

[scrming]

Pointless? The SHO is a performance vehicle and it has Turbos. And its American made.

Also you info above is a bit dated and/or incorrect. A properly set up turbo setup has no lag. My Flex has no lag. Also I laughed about the noise from the BOV. The EcoBoost is incredibly quiet! I wish I could hear the turbos and the BOVs! LOL!

[rez333]

Originally Posted by scrming

The SHO is a performance vehicle and it has Turbos. And its American made.

I meant cars made primarily for high performance, not performance versions of cars designed primarily for passengers or utility.

[JamesNoBrakes]

Yep, I agree that this acticle/text is pretty slanted. Maybe it's from the 1970s too

Originally Posted by rez333

I found this information on the net which answers all my questions (finally!):

Lag
This is perhaps the biggest advantage that the supercharger enjoys over the tubo. Because a turbocharger is driven by exhaust gasses, the turbocharger's turbine must first spool up before it even begins to turn the compressor's impeller. This results in lag time which is the time needed for the turbine to reach its full throttle from an intermediate rotational speed state. During this lag time, the turbocharger is creating little to no boost, which means little to no power gains during this time. Smaller turbos spool up quicker, which eliminates some of this lag. Turbochargers thus utilize a wastegate, which allows the use of a smaller turbocharger to reduce lag while preventing it from spinning too quickly at high engine speeds. The wastegate is a valve that allows the exhaust to bypass the turbine blades. The wastegate senses boost pressure, and if it gets too high, it could be an indicator that the turbine is spinning too quickly, so the wastegate bypasses some of the exhaust around the turbine blades, allowing the blades to slow down..
A Supercharger, on the other hand, is connected directly to the crank, so there is no "lag". Superchargers are able to produce boost at a very low rpm, especially screw-type and roots type blowers.

Kind of, but not really. Lag is not really much of an issue anymore, with twin-scroll turbos, variable vanes, big displacement engines with two smaller turbos (rather than one) and the acceleration/spool up is so fast as to be instantaneous. As a comparission, my SS takes a LOT longer to make decent power and it's "sweet spot" is up very high, but a turbo can hit a lot of torque early. I'd again go to "cost" for the real reason, more expensive to design the turbo, protect it from heat, make sure all the components interact properly, etc.

Efficiency
This is the turbo's biggest advantage. The turbocharger is generally more economical to operate as it as it is driven primarily by potential energy in the exhaust gasses that would otherwise be lost out the exhaust, whereas a supercharger draws power from the crank, which can be used to turn the wheels. The turbocharger's impeller is also powered only under boost conditions, so there is less parasitic drag while the impeller is not spinning. The turbocharger, however, is not free of inefficiency as it does create additional exhaust backpressure and exhaust flow interruption.

It's not just more economical in terms of gas, it will make more power at the same boost levels (internal pressures in the engine), that's a benefit of the efficiency.

Heat
Because the turbocharger is mounted to the exhaust manifold (which is very hot), turbocharger boost is subject to additional heating via the turbo's hot casing. Because hot air expands (the opposite goal of a turbo or supercharger), an intercooler becomes necessary on almost all turbocharged applications to cool the air charge before it is released into the engine. This increases the complexity of the installation. A centrifugal supercharger on the other hand creates a cooler air discharge, so an intercooler is often not necessary at boost levels below 10psi. That said, some superchargers (especially roots-type superchargers) create hotter discharge temperatures, which also make an intecooler necessary even on fairly low-boost applications.

This isn't quite true, that supercharger STILL heats air and puts it into the engine, maybe not as bad as a turbo without an intercooler, but it's also not good for the engine and not near normall-aspirated temps(when air is actually being compressed). I've dealt with a few turbo engines without intercoolers, OMG those things get hot, but still, SC without is also hot. There's also the issue of downstream, the more the turbo is working, the cooler the exhaust is going to the other parts like cats and so on, the intercooler will have a higher chance of melting the cats at the same WHP.

Surge
Because a turbocharger first spools up before the boost is delivered to the engine, there is a surge of power that is delivered immediately when the wastegate opens (around 3000 rpm). This surge can be damaging to the engine and drivetrain, and can make the vehicle difficult to drive or lose traction.

Um, not really, BOV valves and proper tuning/installation mean this isn't an issue. This seems like hyperbole from someone with a poorly tuned blown civic or something.

Back Pressure
Because the supercharger eliminates the need to deal with the exhaust gas interruption created by inserting a turbocharger turbine into the exhaust flow, the supercharger creates no additional exhaust backpressure. The amount of power that is lost by a turbo's turbine reduces it's overall efficiency.

Hmm, I'd assume this is more of a wash if even true, the turbine is harnessing hot exhaust gases, that means you are getting something (compression of air). Hot air comming out the exhaust manifold of the SC engine is not going to cool as it passes a turbine, nor is it going to benefit you in any way once it's left the cylinders.

Noise
The turbocharger is generally quiter than the supercharger. Because the turbo's turbine is in the exhaust, the turbo can substantially reduce exhaust noise, making the engine run quieter. Some centrifugal superchargers are known to be noisy and whistley which, annoys some drivers or makes some very happy!

Hmm, it's maybe a different kind of noise, many turbo systems incorperate "silencers" in the induction to mask the noise, with it removed it's definitely more noisy, then there's the blow-offs and everything. I'd say a little quieter, but when we're really comparing to compressors that can build up to the same boost (usually this is not the case because the SC needs MORE boost to make the same power) they can both be pretty loud.

Reliability
In general, superchargers enjoy a substantial reliability advantage over the turbocharger. When a a turbo is shut off (i.e. when the engine is turned off), residual oil inside the turbo's bearings can be baked by stored engine heat. This, combined with the turbo's extremely high rpms (up to 150,000rpm) can cause problems with the turbo's internal bearings and can shorten the life of the turbocharger. In addition, many turbos require aftermarket exhaust manifolds, which are often far less reliable than stock manifolds.

Kind of, but it's like the top issue: These have been designed arond in most cars, with coolant systems that continue to circulate after shutdown. This is a very strange paragraph anyways, because its not comparing apples to apples, it sounds like comparing a OEM SC to an aftermarket TC, and even if not, it's not like you bolt on the SC and drive away, there's more involved in the install.

Ease of Installation
Superchargers are substantially easier to install than a turbos because they have far fewer components and simpler devices. Turbos are complex and require manifold and exhaust modifications, intercoolers, extra oil lines, etc. - most of which is not needed with most superchargers. A novice home mechanic can easily install most supercharger systems, while a turbo installation should be left to a turbo expert.

Agree

Maximum Power Output
Turbos are known for their unique ability to spin to incredibly high rpms and make outrages peak boost figures (25psi+). While operating a turbocharger at very high levels of boost requires major modifications to the rest of the engine, the turbo is capable of producing more peak power than superchargers.

Not only that, but at the same PSI, you're getting significantly more power output from your engine with a turbo!

Tunability
Turbochargers, because they are so complex and rely on exhaust pressure, are notoriously difficult to tune. Superchargers, on the other hand, require few fuel and ignition upgrades and normally require little or no engine tuning.

I've never agreed with this in the contex of "harder to tune", but this IS the reason they are a bit more expensive. You have to have all the required supporting components (just as you have to for a SC, in fact some of the same components are usually necessary, like intercooler, bigger injectors, higher pressure fuel pump, etc). This gives a tuner what they need to be able to make the system work, and if it's an OEM system, this stuff is usually figured out easily at the factory and designed with safety margins for every possible situation that could be encountered. The reason I disagree with it is that I DID turbo-tuning and I ran just fine with my modificaitons, but I knew my limits.

The end reason is most likely cost and simplicity (which is also cost essentially).

[Kyle2k]

I have to say that it is refreshing that this thread is at least not getting derailed BECAUSE it is a Mustang lol....

[Truck Norris]

Originally Posted by motorhead

So where's the answer to my question. This turbo vs supercharger argument is as old as superchargers and turbos themselves. They each have their place in certain applications.

I want to know how long until this thing Blows it's cookies with a stock bottom end.

Who know's.... JPC's 800+whp stock engine + Paxton 5.0L was plenty strong and didn't blow after heavy track abuse. A lot of longevity comes down to how brutal the WOT hit is on the engine and tune. Roots/ TVS/ Twin Screw superchargers are a lot harder on the engine mainly the rods due to its instant hit of hp and tq vs a centrifugal or turbo which gradually builds power as rpm increase which is much easier on an engine. A turbo is the safest way to make big power since you dont have to worry about slipping blower belts, broken cranks/keyways, brutal WOT hits, pulleys vs eboost2, ect

[scrming]

Originally Posted by JamesNoBrakes

Yep, I agree that this acticle/text is pretty slanted. Maybe it's from the 1970s too

Kind of, but not really. Lag is not really much of an issue anymore, with twin-scroll turbos, variable vanes, big displacement engines with two smaller turbos (rather than one) and the acceleration/spool up is so fast as to be instantaneous. As a comparission, my SS takes a LOT longer to make decent power and it's "sweet spot" is up very high, but a turbo can hit a lot of torque early. I'd again go to "cost" for the real reason, more expensive to design the turbo, protect it from heat, make sure all the components interact properly, etc.
It's not just more economical in terms of gas, it will make more power at the same boost levels (internal pressures in the engine), that's a benefit of the efficiency.This isn't quite true, that supercharger STILL heats air and puts it into the engine, maybe not as bad as a turbo without an intercooler, but it's also not good for the engine and not near normall-aspirated temps(when air is actually being compressed). I've dealt with a few turbo engines without intercoolers, OMG those things get hot, but still, SC without is also hot. There's also the issue of downstream, the more the turbo is working, the cooler the exhaust is going to the other parts like cats and so on, the intercooler will have a higher chance of melting the cats at the same WHP.

Um, not really, BOV valves and proper tuning/installation mean this isn't an issue. This seems like hyperbole from someone with a poorly tuned blown civic or something.

Hmm, I'd assume this is more of a wash if even true, the turbine is harnessing hot exhaust gases, that means you are getting something (compression of air). Hot air comming out the exhaust manifold of the SC engine is not going to cool as it passes a turbine, nor is it going to benefit you in any way once it's left the cylinders.

Hmm, it's maybe a different kind of noise, many turbo systems incorperate "silencers" in the induction to mask the noise, with it removed it's definitely more noisy, then there's the blow-offs and everything. I'd say a little quieter, but when we're really comparing to compressors that can build up to the same boost (usually this is not the case because the SC needs MORE boost to make the same power) they can both be pretty loud.

Kind of, but it's like the top issue: These have been designed arond in most cars, with coolant systems that continue to circulate after shutdown. This is a very strange paragraph anyways, because its not comparing apples to apples, it sounds like comparing a OEM SC to an aftermarket TC, and even if not, it's not like you bolt on the SC and drive away, there's more involved in the install.
Agree
Not only that, but at the same PSI, you're getting significantly more power output from your engine with a turbo!
I've never agreed with this in the contex of "harder to tune", but this IS the reason they are a bit more expensive. You have to have all the required supporting components (just as you have to for a SC, in fact some of the same components are usually necessary, like intercooler, bigger injectors, higher pressure fuel pump, etc). This gives a tuner what they need to be able to make the system work, and if it's an OEM system, this stuff is usually figured out easily at the factory and designed with safety margins for every possible situation that could be encountered. The reason I disagree with it is that I DID turbo-tuning and I ran just fine with my modificaitons, but I knew my limits.

The end reason is most likely cost and simplicity (which is also cost essentially).

Great commentary! And I completely agree with it! Only thing I would add is when it comes to appearance, nothing looks as cool as a nice roots or twin screw sitting on top of the motor!! On the Flex, my turbos are tucked underneath everything and are impossible to see! LOL!

BTW, here is my dyno sheet... Blue is stock tune, Red is with the Livernois Stage 4+ tune... Figure at 2500 RPM i'm making close to 450 ft/lbs at the crank...