DaTruth

I see more turbos than supercharged imports... Why????

kender

I can't speak for everyone but I believe it is due to 2 factors. 1 is a supercharger has a parasitic drag on the engine as it is pulley driven( opposed to a turbo's exhaust driven power), and yes the horspower gains of the supercharger overcome the drag, however lets say a supercharger gives you 80 hp on 8psi you then may loose 5-10 of that on the parasitic drag, where as a turbo gaining 80hp at 8psi has no loss to deduct. the exact losses may be a little off but the principle is the same.

2. your normal supercharger (roots style) is limited in boost and is extreemly difficult to cool the compressed air as the compressor is the intake manifold. This is overcome by the vortech system, which is an awsome system and can be upgraded easily, you just need $4500 -5k to get started. also the vortech systems aren't as easy to find used and customized for your application.

yes turbos have a down side, like lag, but they are easily compensated for if you know what your doing.

DaTruth

You have a point..

Jordan Y.

One reason might be that it's a lot easier to rig up a custom turbo setup than it is to rig up a custom supercharger setup. You can turbo pretty much anything if you have access to a machine shop and have the fabrication skill. The supercharger kits usually have to be custom made for a particular car, and they're usually only offered by one or two major manufacturers. For cars that kits are offered for, they're not uncommon. I've seen many jackson racing supercharged civic si's and integras on the pages of various import magazines, probably more of them than turbo'd si's and integras.

TurboJZA70

this is very incorrect. you can order a paxton or vortec supercarger from the company or a dealer(just the charger not a kit) and cut a mounting plate. get it nicely cut from stainless or alu at tampa lazer.
with this much done the charger is now fixed to the motor. now for the pully. this can be sorced to verious places or even done at home with a lathe. charlee at cmr turbos has been known to make pullys from time to time. yes i simplified the process but anyone that knows a little about fabrication knows these are not hard things to have done.

after this its just plumming and fuel managment. same for a turbo car.

now some engine bays wont accept a supercharger quite as well as they would a turbo due to space but thats all case by case.

I dont believe eaither setup is better, both can be setup right and draw backs taken care of by someone that knows what there doing.

quickcivic

Turbos are much more efficient in creating power then a supercharger.

It uses energy that would be otherwise wasted by the engine and turns it into HP.

I have had both a JRSC and a Turbo on my car and Turbo is WAY better.

turbo-max

i eliminate turbo lag with nitrous

flubyux2

Superchargers do have quite a bit of parasitic loss, they absorb alot of HP just to turn. Like the Roots blower on a Top fuel motor can soak up anywhere from 500-800 HP... but no one really talks about it since they make like 5000 HP.. its only about 10%-12% lost.

turbos use energy that would otherwise be wasted. a general rule of thumb is that only 1/3 of the energy created by the combustion is actually transmitted to the wheels... 1/3 of it is lost due to friction and the cooling system, and the last 1/3 of the power is lost thru the exhaust. the heat of combustion and expansion of the charge is what creates the power, but if the "Cold" piston dome, combustion chamber and cylinder keep absorbing the heat, that means the combustion will expand LESS, and will put LESS force on the dome, and thru the driveline. but we cant make it hotter... youll melt something. So, we have to figure out a way to reduce the amount of power lost else where. If you switch to synthetics and reduce the friction in the engine, that means more power can be used to turn the wheels than trying to turn the crank or cam/s or what have you. the 1/3 of energy escaping out the exhaust is a PRIME candidate for being harnessed. plus, it doesnt really rob the engine of much power at all... you should remember that tehre are a FEW downsides associated w/ turbo's.

Extra heat retained from exhaust
Extra weight from additional plumbing/hardware
Extra backpressure in exxhaust manifold (can be equivalent to manifold pressure or more, depnding on turbo size)

but the advantages of running a turbo and harnessing that "Free" power far outweighs the weight penalty and other downsides. Plus, they are more efficient being that they dont rob power/torque from the crankshaft which could be used to drive the wheels.

also, the benefit it has overe SC's is that its not constantly running and trying to push air. any belt driven SC is constantly pumping air, meaning that its working to compress/move air, even during cruise conditions. now, while some aftermarket companies have divised a way to incorporate a bypass valve that the air being compressed/pushed by the SC is recirculated freely back into the intake piping and is not trying to be pressurized inside the intake manifold; this means less backpressure/resistance and less work must be done by the engine.

plus, roots type blowers have to seal against the case... they use teflon strips which wear out and have to be replaced... which is why finding a 6-71 GMC blower at a Swap meet might nto be such a great deal considering how much itll cost to do a much-needed rebuild. turbos will last for 100k miles easily, IF PROPERLY CARED FOR. if cared for properly and not over boosted, surged, redlined, etc... they can work as well @ 100k miles as they did at 5 miles.

the reason Imports use Turbos rather than blowers is because the small displacment/low torque motors cant afford to have a big, power-robbing parasite integrated into their pully system. small displacment motors can make TONS of power, but only when they are ingesting tons of air/fuel.. and that doesnt happen in the bottom end of the RPM band, so its just that much harder to operate the SC. turbos dont rob ANY power when operating under manifold vaccum... if they do rob any power, it would be due to back pressure in the manifold but its very small.

btw, Turbo Lag is just a courteous head start. its how i get out of the hole w/o annihilating my tires.

Tony

Um if you are arguing that a supercharger is easier to fab up, then get your head examined, I would much rather fab up exhaust pipe to drive a turbo than a belt to drive a pully. flybyu pretty much hit the neail on the head hoss.