Turbocharger and Supercharger

To all the motor heads out there I have a theoretical question about supercharging and turbocharging an engine. Would it be possible to do both to the same engine without killing the engine? It would seem as though it would to me, because turbo increases mainly horsepower while superchargers increase the torque. Turbo is run off of the exuast and superchargers use the actual engine to run. It seems as though to me they could run together for forced induction because they use different components and make different power torque= take off Hp= high speeds. Can someone tell me if I am wrong or not.
Thanks






"There is no replacement for displacement"
Whoever said this never saw my 2.6 Liter 600 horsepower engine.

Yes, there used to be a dual sc and dual turbo cav that was a drag queen.

Yes it is possible to supercharge and turbocharge a motor. Not practical though.

Who said Superchargers only make Torque? You must not of heard of Centrifugal Superchargers, they boost just like turbo. And in some cases can out perform a turbocharged setup.

Look at the Semi-trucks of America, most of them are turbocharged. And they make 400hp, but 1200ft-lbs of torque. Figure that one out tarzan.


ECOT3C... I'm assuming it was 4 cylinder Cavalier that had dual superchargers and dual turbochargers? I find that hard to believe seeing as the Cavy engine bay isn't large enough for all that to fit... and a TT setup on a 4 cylinder... why?

Whatever anything is possible with money, find me a picture of this car. Surely a car with that insane setup would be on the web. I'm really interested in seeing this 'drag queen'.

Man you didn't have to call me tarzan. That is why I asked the question. I had heard that Turbo made mainly Hp, and Superchargers made mainly torque. But apparently that isnt true. Which is what I wanted to find out. Thanks.... I guess.

As for the 1200 ft-lb of torque I dunno its probably because it isnt a 4 banger like the imports that I was referring to. I thought this was an import forum.

Man you didn't have to call me tarzan. That is why I asked the question. I had heard that Turbo made mainly Hp, and Superchargers made mainly torque. But apparently that isnt true. Which is what I wanted to find out. Thanks.... I guess.

As for the 1200 ft-lb of torque I dunno its probably because it isnt a 4 banger like the imports that I was referring to. I thought this was an import forum.



You're right, I didn't have to call you Tarzan... sorry. But it was still funny. :lol:


Whoever told you Turbos only make horsepower was wrong. It all depends on how the motor is setup. Most imports rev high, thus turbo's are prefered cause they can be in the boost range longer making more power and pull harder. If that makes any sense then good, I can't really think of a better way to say it at the moment. I've got a headache. :banghead::lol:

This forum isn't just for Imports, it's for all cars of all makes.

He was thinking of roots type blowers. It would be a kickass setup, (on a V-type engine), to run a blower on top with twin turbos... but it'd be more trouble than it was worth really... you'd have to find some way to relieve the blower of its pressure after a certain RPM or pressure was met, WITHOUT evacuating all the boost put into the intake by the turbos, so that when the turbos kicked in you wouldn't end up with some ludicrous amount of boost and it would take the workload off of the blower at higher RPMs. The air induction would be a nightmare too. Heat, would be another factor since roots type blowers make it and turbos certainly make it, have fun cooling all three of them off.

Talk about bragging rights though! :D

I know of two cars that imploy 1 supercharger and 1 turbo. one is a v6 mr2 that is a turbo magazine project. the other is a 3800 swaped fiero.
I've been thinking about doing this to my 3800 once it's running.

then again(alittle off topic here) I was told by a 16 year old that it will blow my engine up no matter what. I told him about the other cars but he didn't beleave me and continued to say it will blow my engine up. currently he has no running car and says his vw GTI will be the fastest car once he swaps a 16valve head on it. he says he's going to have a reputation on the street. I say go back to your FnF club you stupid ricer!

sorry had to vent there.

it will work with the right setup.



marcus

Well, you can twincharge a car, if that's what you mean. You have both a sc and turbo, and switch between them at a certain rps (3500 or so.) Not sure of the logistics of it though, and you aren't running both at once.

To all the motor heads out there I have a theoretical question about supercharging and turbocharging an engine. Would it be possible to do both to the same engine without killing the engine? It would seem as though it would to me, because turbo increases mainly horsepower while superchargers increase the torque. Turbo is run off of the exuast and superchargers use the actual engine to run. It seems as though to me they could run together for forced induction because they use different components and make different power torque= take off Hp= high speeds. Can someone tell me if I am wrong or not.
Thanks

"There is no replacement for displacement"
Whoever said this never saw my 2.6 Liter 600 horsepower engine.

What I think you mean is fundamentally correct, but your terminology is incorrect.

Engines do not create horsepower, they create torque (rotational force). Horsepower is calculated by (torque*rpm)/5252. It shows the force that can be applied relative to distance over a period of time.

Both the torque rating and horsepower rating are important in determining vehicle performance, though simple peak numbers aren't nearly as helpful as dyno graphs. The curve of interest is really the torque curve.

A supercharger will tend to increase low-end torque, while turbos tend to increase high-end torque which as you can see from the equation, will increase the peak horsepower.

Using both a turbocharger and a supercharger has been done, but is not the easiest to do. Heat will be an issue as it always is with forced induction. The complexity of plumbing the system will also be difficult, as it is not a common practice. Also, the actual increase in performance is probably not worth the money/effort.

Using the correct cam, rockers, compression ratio, etc. to balance the forced induction you use will likely give you the performance (the nice broad torque curve) you want.

On the otherhand, using both is pretty sweet if you have the time and money. :smile:

Hope this helped.

^ Thank you for posting that, because I really didn't want to type that all out. Horsepower and torque are intertwined, you can't change one without changing the other. Just by moving the torque peak around in the RPM range, you can get vastly different HP numbers with the same amount of torque. I believe this is where the "Domestics and supercharges are for torque, imports and turbochargers are for hp" myths come from. In general, a small engine revs higher because of the inertia and balance, so "imports" (quoted because of things like the Focus or Neon are included in this) rev higher, and when looking at their peak numbers, the hp number will be higher in relation to the torque number than in a "domestic" which generally has a lower max RPM. By the same principal, Supercharged cars generally make boost lower in the rpm range, making the torque appear higher in relation to the hp than on a turbo car where it takes a moment to spool and therefore doesn't make the torque till later in the powerband.

^ Thank you for posting that, because I really didn't want to type that all out. Horsepower and torque are intertwined, you can't change one without changing the other. Just by moving the torque peak around in the RPM range, you can get vastly different HP numbers with the same amount of torque. I believe this is where the "Domestics and supercharges are for torque, imports and turbochargers are for hp" myths come from. In general, a small engine revs higher because of the inertia and balance, so "imports" (quoted because of things like the Focus or Neon are included in this) rev higher, and when looking at their peak numbers, the hp number will be higher in relation to the torque number than in a "domestic" which generally has a lower max RPM. By the same principal, Supercharged cars generally make boost lower in the rpm range, making the torque appear higher in relation to the hp than on a turbo car where it takes a moment to spool and therefore doesn't make the torque till later in the powerband.
Obviously they are intertwined, as instantaneous horsepower and torque can be calculated be converted via the (rpm*torque)/5252 equation. So if your peak torque is the same magnitude at a higher rpm, peak horsepower will increase. If you did a mod and measured the change in horsepower (if it could be measured directly; dynos measure torque, then mathematically calculate horsepower), there would also be a change in torque. Both peak values could change, at different rpms even.

It all gets confusing because all people normally talk about is this peak horsepower and torque, which is what you're talking about, and not the entire torque and horsepower curve.

to add further confusement a turbocharger is actually a form of supercharging. So you can actually call it a supercharger.

completely useless i know

some thing to do with shortening
turbine powered supercharger. I think thats the term though i'm sure i'm quite wrong for the time being.

Thanks a lot guys that cleared up a lot ffor me.

Its an old as hell, 86 or something cavalier hatch that was a v6 now is a v8. Ive been looking for the sqaid car but i havent seen it for a while.

to add further confusement a turbocharger is actually a form of supercharging. So you can actually call it a supercharger.

completely useless i know

some thing to do with shortening
turbine powered supercharger. I think thats the term though i'm sure i'm quite wrong for the time being.



To further add to the confusion the old Detriot Diesels were both Supercharged and Turbocharged... but they don't make those any more.

Whatever anything is possible with money, find me a picture of this car. Surely a car with that insane setup would be on the web. I'm really interested in seeing this 'drag queen'.
http://www.dobbertinhydrocar.com/J2000%20Engine.htm

Here is a twin supercharged twin turbocharged Pro Street 1985 Pontiac J-2000 built by Rick Dobbertin. I believe this has come up in another thread but I'm not sure. Looks pretty though...

*DROOL*

They had a supercharged and turbocharged MR2 in Sport Compact car's tuner challenge. The sucker dynoed at 300 rwhp, that's from 1.6 liters of displacement.

Ok, I'll start with the basics here.

Twincharging is the practice of using both a supercharger, or more than one supercharger, and a turbocharger, or more than one turbocharger, on the same engine.

There are two basic ways to go about it, turbo into supercharger, and supercharger into turbo. Neither have been shown to really have any benefit over the other, but you'll find a half dozen theories to support either argument.

The basic theory of how it works is centred around efficiency ranges. The common practice is to take a large turbocharger, that would normally have an efficiency range too high to be streetable on the engine, and a supercharger that is driven at a speed that guarantees it's efficiency range is quite low in the rpm range.

Necessary for the design are bypass valves, that route air around the supercharger at higher rpms, when the supercharger is out of it's efficiency range. Also very helpful, but not entirely necessary is the use of an electromagnetic clutch on the supercharger, which disengages after the bypass valves are opened or closes.

The idea is, the bypass valves open or close, depending on the setup, when the efficiency ranges of the turbocharger and the supercharger overlap, making for a seamless transition. You get the best of both worlds, great low end torque, and fantastic high rpm power. As long as you can keep the motor together, the sky is the limit, and it's still streetable.

To my knowledge, the only widespread and successful twincharging setup was the HKS turbo kit for the Toyota 4A-GZE, which was used mostly in the MR2 MK1, although it was also used in the AE92 generation Corollas with the 4A-GZE, IIRC.

There is also an economy car sold in Asia that is twincharged, but it has an exceptionally small engine, and is twincharged not for performance, but for driveability. I can't remember what it's call though...

Here are some links

http://geocities.com/motorcity/lane/1231/twincharging.html

http://geocities.com/motorcity/lane/1231/gerald.html

I wasn't terribly impressed by the guy's build in the first link, but the dyno results for the other guy's engine speak for themselves, as well as his 11 second time slip.

All you need to know about it is said in the post above. Let me ask this though, is the little gain you get from running this setup really worth it? I mean, you can only get so efficient of a turbo on a street engine before you start running out of accuall airflow the motor can support with out either blowing the bottom end out or just pre-deationating the piss out of the motor. I run 27 PSI on 118 torco fuel and my uncle has a Turbo Trans Am and he run 30. my car has very mild lag and my uncles car is just a little lazy. The top end of the two cars though is sooo worth the lag. I guess what I am trying to say is that by the time you spend all the money and effort into doing it. a plain turbo/supercharged car will be so far ahead of you it is not even funny. Just my thoughts about it.

supercharger + turbocharger = twincharged

HKS used to offer a turbo manifold for the supercharged MR2.
This allowed you to run both compressors.

See here:
http://shell.deru.com/~sgn1/AW11/mod/gsa.htm

http://mr2.com/OWNERS/GeraldA.html

http://www.4ag3sg.co.uk/twincharge2.htm

.. there is more. Do a google on "hks twincharge"