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-   -   Which is more effective Turbocharger or Supercharger ? (https://www.team-bhp.com/forum/technical-stuff/2184-more-effective-turbocharger-supercharger-7.html)

Both SC (superchargers) and TC (turbo chargers) have similar roles. They both pressurize the intake charge and effectively increase the engine compression ratio.

Turbos have a some lag (very little with the new variable vane type) but do not take up engine power.

SCs have no lag and give you power right from idle. But will take up a good chunk of hp at high rpms.

SCs are very sensitive to dust, and will quickly fail if dust gets in. This pretty much means they are not suited to Indian conditions.

Also, TCs are cheap, and SCs, are expensive. So case closed in favor of TCs.

Turbo is driven by exhaust gas, supercharger is driven by a belt just like your alternator. Both are pumps that cram air into your motor for more powerful detonations in the cylinders.

I have wondered if you could not rig a small tank that would accumulate air via a pump, or even make pure oxygen you chemists, while under normal engine load cruising but then discharge under pressure into the air intake when there is hard acceleration.

Thats what Wide-Open-Throttle Nitrous Oxide Injection is! :)

Thats the idea of NOS. Instead of air, Nitrous Oxide is stored in a tank and Nitrous Oxide under the extreme temperature disintegrates into one molecule of Nitrogen and two molecules of Oxygen. This additional Oxygen is what helps to burn more fuel and develop those extra horses. Nitrogen is said to have a cooling effect inside the combustion chamber.

also nitrous oxide will have the safety of not blowing up in your car unlike the risk of a oxygen cylinder.

Hi RedMM, do you mean to say dust in the air? But SC's are completely in closed environment, its not opened to air like TC's intercoolers, please can you explain me more on this?


Sankar, thank you for explaining how the Nitrous works, I like the chemical formula that you explained, I remembered my school and college days. Which one do you prefer dry or wet Nitrous?



Has any TBHP member supercharged there car? In bangalore the current trend in moding the car is getting the SC installed all this days when I used to listen to only TC's all of sudden I am hearing about SC's.

You buy NOS. I am talking about simply storing air or oxygen in a tank while cruising and letting it go into the intake under throttle.

I feel that supercharger are relatively better than Turbochargers.

1)
Supercharges dont have any sort of lag. They are turned by the crankshaft so higher the rpm , the more boost one will get.

2)
For not very high rpm driving i.e. driving in normal road conditions, supercharger wont be a baggage on the power figures of engine.

Yes I mean dust in the air.

SC and TC have the same principle. They both compress air and force feed into the intake manifold of the engine. Both can be use intercoolers to cool the air charge prior to the intake manifold, which increases power.

SCs are roots type of blowers that have lobe style screws with very tight tolerances. This is why they make pressure at very low rpms. If you suck in dust due to a ripped intake pipe or K&N filter in a high dust environment, the SC will get damaged.

TCs on the other hand rely on free exhuast gas velocity and spin at ultra high rpm to give boost. This does not necessitate ultra tight mechanical tolerances needed by SC.

Hope this clears up your question.

Regards,

My pleasure Vinay. That was just a basic explanation. Dry or Wet i guess wet is safer because additional fueling is also taken care of in the wet system. But my ideal preference , if i were to choose between a turbo/super job a NOS, would be a turbo/supercharger because once the NOS tank is dry the fun is over.

Turbochargers compress and heat the air thus needing intercooler to cool the charge. But screw & lobe type superchargers they move the air faster they don't compress the air as much as a turbo, thus heat buildup is generally lower. Superchargers are positive displacement air pumps. Thus like RedMM340 said have very tight clearances between their moving parts and they're sensitive to heat as well. Turbine type superchargers are more like turbos driven off the cranks.

Thanks team for explaining me so many things on SC. If there is any other disadvantage in SC other than dust getting in, please list it out.

Thanks for that info RedMM, I had never thought about that.

What are the tolerances like? and is fine dust and issue or only larger particles which may come through if the filter is ripped etc. ?

cya
R

size of the tank even for a decent use will render this idea useless ......

Also, SCs are easier to install and remove. Turbo setup is way more complicated.

Hi Rehaan,
Don't know the specific tolerances. But they are very tight, so fine dust like we have in plentiful supply here are larger particles and will chew up the insides of a supercharger.

Plus the SC has a much high cost and as far as I know there are no SC production cars here in India. With the possible exception of Mercedes? So in an extremely price sensitive market like India, Superchargers will not proliferate. Even in the U.S., SCs have just a fraction of the marketshare of turbos.

Of course Mercedes' goal with SC motors is to make their 4 cylinder units feel like V6s or V8s. This is the main reason for them adapting "kompressors" to their newer motors. There is really no other major car manufacturer that I can think of that uses SCs in mass production.

Really, SCs are better suited to larger (lower revving) engines that have low end torque to turn a large serpentine belt accessory (Supercharger). Superchargers on large V8 motors can chew up 60+ horsepower at 5000+ rpm, so are just not that efficient at high rpm. SC's have also been popularized by after market tuners such as TRD (Toyota Racing Development) and others, because of the fact that you can very simply bolt them in with less modification than a turbo retrofit.

Another point to consider, is that turbos really are well suited to small engines that like to rev up. The turbo boost curve very nicely matches the small engine power curve and just enhances it.

This is strictly an academic discussion for the Indian automotive scene, since turbos are cheaper, less sensitive to dust, and match typical small engine power curves.

Regards,

Gaurav