Turbo Vs. Super

[Polygon]

Originally Posted by 454Casull

None? Relative advantage? Or no advantages whatsoever?

Can you elucidate?

In my opinion, none whatsoever.

[454Casull]

Originally Posted by Polygon

In my opinion, none whatsoever.

From my perspective:

Pros

Instant boost
Negligible power loss due to supercharger at higher RPMs
Maximum boost available throughout rev range

Cons

Complexity of tubing
Doesn't fit in all cars

[MustangRoadRacer]

I've seen a car with 2 turbos AND 2 superchargers.
It can be done, but the fact is, a twin turbo is enough for just about any application.
to get really strange, ford used 4 turbos on the GT40 concept.
it had 1,000 hp, so I guess it worked ok!

[beef_bourito]

Originally Posted by MustangRoadRacer

I've seen a car with 2 turbos AND 2 superchargers.
It can be done, but the fact is, a twin turbo is enough for just about any application.
to get really strange, ford used 4 turbos on the GT40 concept.
it had 1,000 hp, so I guess it worked ok!

how would you get 2 supers in there, are they like side-by-side on the hood?

[454Casull]

Originally Posted by MustangRoadRacer

I've seen a car with 2 turbos AND 2 superchargers.
It can be done, but the fact is, a twin turbo is enough for just about any application.
to get really strange, ford used 4 turbos on the GT40 concept.
it had 1,000 hp, so I guess it worked ok!

You mean the GT90.

[Neutrino]

Originally Posted by MustangRoadRacer

I've seen a car with 2 turbos AND 2 superchargers.
It can be done, but the fact is, a twin turbo is enough for just about any application.
to get really strange, ford used 4 turbos on the GT40 concept.
it had 1,000 hp, so I guess it worked ok!

well the veyron has 4 turbos too....its the only car stated for production that has that many i believe

[Sluttypatton]

Would anyone care to take a stab at why 4 turbochargers are needed? I'm not sure why that was necessary on the Veyron. But it seems to me that it may have more to do with bragging rights than actual performance. Granted, it does have a 16 cylinder motor, but each cylinder is only 0.4995625 liters in displacement. When compared to 0.625 liters per cylinder for the Ford 5.0L, one can see that the size of each cylinder isn't actually that large. In fact, if the cylinder size remained the same but the motor were only an 8 cylinder, then it would be just shy of 4 liters of displacement, not a huge V8. If a single turbo can feed a proportionately larger displacement V8 efficiently, it stands to reason that two would be adaquate to feed the W16, especially since it is more than 2 liters smaller than two V8's.

[454Casull]

Originally Posted by Sluttypatton

Would anyone care to take a stab at why 4 turbochargers are needed? I'm not sure why that was necessary on the Veyron. But it seems to me that it may have more to do with bragging rights than actual performance. Granted, it does have a 16 cylinder motor, but each cylinder is only 0.4995625 liters in displacement. When compared to 0.625 liters per cylinder for the Ford 5.0L, one can see that the size of each cylinder isn't actually that large. In fact, if the cylinder size remained the same but the motor were only an 8 cylinder, then it would be just shy of 4 liters of displacement, not a huge V8. If a single turbo can feed a proportionately larger displacement V8 efficiently, it stands to reason that two would be adaquate to feed the W16, especially since it is more than 2 liters smaller than two V8's.

V8 = 2 turbos
W16 = 4 turbos?

Probably a combination of packaging and bragging rights.

[SaabJohan]

Bugatti also used 4 turbochargers on the EB110 if I remember correctly. The use of several small turbochargers instead of fewer larger ones makes the boost to come a little earlier and the exhaust manifolds can be made shorter.

[Neutrino]

Originally Posted by SaabJohan

Bugatti also used 4 turbochargers on the EB110 if I remember correctly. The use of several small turbochargers instead of fewer larger ones makes the boost to come a little earlier and the exhaust manifolds can be made shorter.

probably that is part of the reason...but i would be willing to bet - as patton said - that the main reason for 4 turbos was bragging rights

[Holyterror]

Holy crap... there have been several ambiguous or erroneous statements made over the course of this thread that nobody addressed. I wish I'd gotten in on it sooner, but I guess I'll just have to play catch-up.

Originally Posted by disco192
People need to grow up and realize that cars change with technology. Turbos dont have lag and you dont need low end torque (eliminating superchargers "advantage").

I don't want to get into a big argument over this, but...

1. Turbochargers DO still have lag
2. Low-end torque is VERY IMPORTANT in many applications

In a world of technological ideals, there is no turbo lag. In the real world, it is still very much a part of reality. I don't recall this topic being limited to drag racing, and the idea that low-end torque is not important to a street car is absolute madness. I don't think I need to elaborate here.

As for twincharging (super + turbo), it's obviously expensive, requires a lot more plumbing, and must be controlled. Nissan did it successfully with the March Super Turbo (engine MA09ERT), and HKS briefly made a kit for the MKI MR2 - there are reportedly four of these running around the U.S. Done properly, it has the effect of a sequential turbo system with negligable lag, more low-end grunt, and serious bragging rights. It also gives you the disadvantages of both systems at different times. It's a major undertaking, and not worth the trouble to most.

About the "quad turbo" setups: it seems superfluous to me, but there are two main advantages on a very large engine. First and foremost, there is faster spooling (although twin ball-bearing turbos should still be plenty fast). Second, there is plumbing. Routing 16 pipes to two turbos can be difficult (space-engaging and inefficient at best). But the W16 should never have turbos anyway, the con rods being too skinny to stand up to serious power. Heck, I don't think the W16 should be built at all. The V16 is still more feasible, although I can't see any real advantage over the technically perfect V12. But that's a discussion for another day...

Okay, now that I've rambled about side issues, lemme tackle the main turbo vs. super argument. Superchargers, in any non-turbo form, take power straight from the crank. Supercharging will always decrease an engines ability to rev. Power and torque curves are often changed dramatically, making it feel like a totally different engine. The power increase is linear, making it a very pleasant car for daily driving, etc. Installation is simpler than turbo, and it has its own oil supply. Unfortunately, maximum boost can only be produced at one engine speed (usually redline), which makes the turbo much more preferable to me in racing. Plus, superchargers max out at only a fraction of the boost that most turbos can produce (although Saab supposedly has a 40 psi super on its experimental variable compression engine). It's less efficient, wears out faster, kills revability, and just plain can't make the kind of boost that a good turbo can. I think you can already see which way I'm leaning.

Turbochargers require more exhaust plumbing, oil lines, extra (possibly expensive) components for high boost levels, and time to spin down before shutting the engine off! Turbo lag is the most quoted downside, although somewhat alleviated by ball-bearing turbos and low-inertia turbines (as well as titanium shafts, coatings, and other advanced technologies). Superchargers give power from low speeds, offsetting the lower static compression that forced induction necessitates; turbos do not. That is the essence of turbo lag. Power is derived from exhaust gas, which is pretty much free energy. Turbos do, however, create some backpressure in the exhaust system, thus hurting exhaust gas scavenging. It's a pretty minor trade-off. They do not change power and torque curves as dramatically as superchargers, and large, slow-spooling turbos do not make for fun daily drivers. Turbos make more boost, do not depend on engine speed, last longer (if not abused), and look cooler (okay, that's extremely subjective). That's my take on it, in a nutshell.

Um, any questions?

[Polygon]

They look cooler, and IMO sound much cooler as well. I never liked the whine of a super.

[Sy.Berian.Wulf]

i think somebody has miss the whole point here... which is better? super or turbo...

Turbo is by far better...... yes with a few more pricely gadgets you can increase HP dramaticaly...

Along with a turbo, you put a wastegate...somebody forget that???
wastegate stores precious air needed to get the revs back up to the speed needed to have to turbo work efficiently and with a intercooler to bring the temp of the air down... u got a mean hp increase to mess with.... logicaly one puts a blow off valve in the system to prevent a bad surge in air pressure and potentialy damaging parts..... theres 1 rule with a turbo....

when it breaks... something else breaks with it...

supercharger has only the belt speed with which to drive its induction....thats no fun, power at low revs is useless.... whos gonna drag at 3000 rpm???... anyone?

[johnnyBgood]

Well there are different types of superchargers. A centrifugal supercharger has the same compressor housing as a turbo, but it is attached to the accessory belt instead of driven off exhaust. Because it is almost the same design as a turbocharger, it creates massive power in the upper RPM range while creating almost none while in lower RPM's.

And where do you get that a wastegate stores air? The wastegate is there to control boost. When the turbo system hit's max boost, the wastegate is fully open letting the exhaust out a different route than the turbine.

An FI system is only as good as it is tuned. Some cars are made with superchargers and therefore, why add a turbo and remove the blower? Just increase the psi of the blower.

[beef_bourito]

Hey, i'm a little confused, you guys are saying that with superchargers you only reach max boost at redline but here they say you can reach full boost from just off idle. Can someone explain?