: Supercharger vs. Turbocharger?



orconn
07-31-11, 05:44 PM
I have owned cars with a supercharger, and I have owned cars with turbo chargers, and for my money the supercharger wins hands down. The supercharger didn't inflict the phenomenon of "turbo lag" on the me. This is very important to me as most of my driving is in a city "stop and go" environment. Over the years I have tried several turbocharged cars and to be honest, while improved over the 1980's models there was still a lag at start up. The supercharged cars eliminated that lag and drove like much larger engined conventionally aspirated cars.

I know now with "twin turbos" this lag is supposedly finally eliminated, but I wonder why the "twin turbo" set up would be superior to just a single supercharger?

amunderdog
07-31-11, 08:29 PM
It takes HP to run a supercharger and it usually causes hood clearance issues.
Turbo chargers run off wasted engine energy. So by running two; one small - one medium sized they can get the small one to spin up quick and hold out until the other one comes on line.

drewsdeville
07-31-11, 09:23 PM
+1 for turbocharger(s) here.

Jesda
07-31-11, 10:03 PM
As a driver, I prefer the feel of supercharging.

Turbos are generally more efficient, but I'm not concerned with that.

I~LUV~Caddys8792
07-31-11, 10:14 PM
Same here, as a driver, I prefer the feel of supercharging. When a supercharger is in good tune, the power comes on like an OHV V-8. Lots of low end torque, good mid range and decent top end power, but the emphasis is on the low-mid range. Most turbos I've driven don't have the low end torque of a supercharged motor, and they're meant for the mid-high end power.

Turbos are getting a lot better as of recent though, with greater low end torque than before, and in some of the expensive cars, you don't feel the turbo kick in nor hear it's whistle. The BMW twin turbo 3.0L I-6 is a stunning example of this. But like someone else said, having two smaller turbos helps with this a lot.

I'm not sure if it's still this same way, but I knew a guy who had a '91 Talon TSi and after aggressive driving, he had to let it idle for a few minutes to let the turbo cool. It was very important that he'd do that, otherwise the oil wouldn't cool and it would sit in the turbo and hurt the gaskets. That is a minor annoyance of a turbocharged engine.

orconn
07-31-11, 11:14 PM
I've never driven a turbo car that could touch a supercharged car as far as over all driveability. It seems to me all this "twin turbo" gobbledygook is complicating the system and in the long run increasing cost of maintenance.

ga_etc
07-31-11, 11:31 PM
Same here, as a driver, I prefer the feel of supercharging. When a supercharger is in good tune, the power comes on like an OHV V-8. Lots of low end torque, good mid range and decent top end power, but the emphasis is on the low-mid range. Most turbos I've driven don't have the low end torque of a supercharged motor, and they're meant for the mid-high end power.

Turbos are getting a lot better as of recent though, with greater low end torque than before, and in some of the expensive cars, you don't feel the turbo kick in nor hear it's whistle. The BMW twin turbo 3.0L I-6 is a stunning example of this. But like someone else said, having two smaller turbos helps with this a lot.

I'm not sure if it's still this same way, but I knew a guy who had a '91 Talon TSi and after aggressive driving, he had to let it idle for a few minutes to let the turbo cool. It was very important that he'd do that, otherwise the oil wouldn't cool and it would sit in the turbo and hurt the gaskets. That is a minor annoyance of a turbocharged engine.

That why they came out with turbo timers. You see them a lot on modified turbo cars that are really built for performance. The turbo timer keeps the turbo spinning after the car has been shut off so you don't have to let it sit and idle. With a stock turbo car you don't have to worry about it so much unless you have just really been driving the snot out of the car.

As far as preference between a turbo and a S/C car, it depends on what the car's intended purpose is. In a daily driver I would prefer S/C'd. Less maintenance to worry about, no turbo lag, etc. But for a weekend toy, a turbo car is much more fun. There's just something about planting your foot, watching the RPMs build, and then the car pushing you into your seat when the boost comes in. The only problem, though, is that with older turbo cars most of them had pathetically weak engines without the boost.

ben.gators
07-31-11, 11:45 PM
+1 for supercharger... I have very limited experience with turbo. It was a Saab 900 and to get some power I needed to floor the gas and wait a while.... It was enough for me to dislike the turbocharger....

dkozloski
07-31-11, 11:48 PM
Supercharger=low end torque and throttle response.

Turbocharger=power lag, a strong top end, and exhaust valve heat problems..

orconn
07-31-11, 11:55 PM
Supercharger=low end torque and throttle response.

Turbocharger=power lag, a strong top end, and exhaust valve heat problems..

Nanook has spoken, and as usual he speaks the truth!

Submariner409
08-01-11, 09:54 AM
Seems like every day brings a new aftermarket supercharger kit or dealer RPO for new model cars...........and the new rotor patterns and spirals are impressive. The new helix blowers put the early GM/Roots equipment to shame.

brandondeleo
08-01-11, 06:33 PM
http://www.youtube.com/watch?v=CTwc8N-sjw4

JimmyH
08-02-11, 03:49 PM
It takes HP to run a supercharger and it usually causes hood clearance issues.

^plenum supercharger, roots type

centrifugal superchargers don't have that issue as long as there is room in front of the engine


Today's turbos aren't like those from 10+ years ago. They generally have no lag to speak of, and don't necessarily mean no low end. My stepdad has a 2008 GTI, and it has almost as much low end torque as my LS3 V8. And unlike my LS3, its turbo4 runs out of breath towards redline. The exact opposite of what I would have expected from a small turbo4. You can lock it in 4th gear and happily chug around town all day.

Aron9000
08-03-11, 01:12 AM
^plenum supercharger, roots type

centrifugal superchargers don't have that issue as long as there is room in front of the engine


Today's turbos aren't like those from 10+ years ago. They generally have no lag to speak of, and don't necessarily mean no low end. My stepdad has a 2008 GTI, and it has almost as much low end torque as my LS3 V8. And unlike my LS3, its turbo4 runs out of breath towards redline. The exact opposite of what I would have expected from a small turbo4. You can lock it in 4th gear and happily chug around town all day.

In the quest to cure turbo lag, one trick is to install a slightly smaller turbocharger, as in the Golf GTI and other VW/Audi products with that same motor. The smaller turbo spools a lot quicker, so you get a nice fat torque curve down low in the rev range. The tradeoff is it runs out of steam in the upper rev ranges near redline, right where a larger turbo would be hitting its sweet spot. Of course the larger turbo would have more lag.

Anyways, I prefer a supercharger since there are a lot less parts/complexity in the car. Of course my personal preference is just a big old honkin v8 like the LS3 in the Vette, the Hemi, or Ford's new 5.0 DOCH monster. The Vette's all alumium LS3 is suprisingly light weight and compact, a lot of times being lighter than many v6 motors.

Jesda
08-03-11, 06:50 AM
I think I have 30hp off the line and 180hp at redline.

I~LUV~Caddys8792
08-03-11, 07:20 AM
I think it was the 1993-98 Toyota Supra that was one of the first twin turbo cars to install two different sized turbo units, a smaller one to get the boost up, and then a larger one to take the boost to ridiculous levels once the RPM's were up.

JimmyH
08-03-11, 12:34 PM
In the quest to cure turbo lag, one trick is to install a slightly smaller turbocharger, as in the Golf GTI and other VW/Audi products with that same motor. The smaller turbo spools a lot quicker, so you get a nice fat torque curve down low in the rev range. The tradeoff is it runs out of steam in the upper rev ranges near redline, right where a larger turbo would be hitting its sweet spot. Of course the larger turbo would have more lag.

Anyways, I prefer a supercharger since there are a lot less parts/complexity in the car. Of course my personal preference is just a big old honkin v8 like the LS3 in the Vette, the Hemi, or Ford's new 5.0 DOCH monster. The Vette's all alumium LS3 is suprisingly light weight and compact, a lot of times being lighter than many v6 motors.

Someone was telling me briefly about the turbo in the GTI, just like you said. Setup the way it is, it makes a GREAT little commuter car.

Yes, the LS3 is a great engine. It has really good (not great, but close) torque down low. But it screams to redline. Which is just mind-boggling for a 6.2 liter pushrod engine. And yes, it's pretty light. The biggest advantage of OHV. Add any kind of forced induction to a V6, and it outweighs the LS3. If a supercharger you require, the magnacharger kit for the LS engines is a bolt-on, and not that expensive.