Just wanna know the pro's and con's of both and if anyone has done a supercharger on a n/a rb30.......I need heaps of info and am leaning towards supercharging...... Cheerz for info...

With the amount of aftermarket products around for the RB30 turbo, there isn't much point supercharging it. It will probably end up costing you more to supercharge it and get less power than if you were to turbocharge it as well.

Quote: It will probably end up costing you more to supercharge it and get less power than if you were to turbocharge it as well. Where did you pull that bull**** from? On the cost side you might be right, but as far as performance goes, it depends on what supercharger/turbocharger package you go for. If you consider a centrifugal supercharger, they're VERY similar to turbos! For driveability, I'd go the supercharger route any day.

Muzza is correct. Of course you would get less power from the blower. Think about it. 1. The blower belt runs off the crank. Although the boost it produces adds power, it is sapping power from the engine to do so in the first place. 2. The blowers power is restricted to the gearing of the pulley you run. Its not like a turbo where you can just go out and buy a bleed valve to add more boost. And to upgrade an overdrive pulley for the blower will not be cheap. 3. The turbo runs off the exhaust so as long as you have the right mods, turning up the boost is easier/cheaper thaan a blower. If you are going to go for big power out of either than an intercooler, worked heads, upgraded fuel system etc will all be necessary. The blower will have a better initial torque curve, but if the blower is set to a 9psi rating, it will nly hit 9psi of boost at the top of the rev range. Consistanly building in boost pressure. The turbo will hit 9psi very early and slam you into your seat as you fly up throught the revs..... such a beautiful feeling Its easier to get 20psi out of a turbo than it is out of a blower (not stock turbo). As for driveability, its all a matter of personal preferance. You will always be on boost with the blower where as with the turbo you can put around in vaccum, not very likely but it is possible. I am assuming that you are going to build the engine properly and change pistons etc. so at the end of the day it wil work out around the same amount of cash and the turbo will come out with a better power figure. At the end of the day though, just ask yourself what you really want. If you want to be different and arent after huge gobs of power then a blower would probably work for you. I recommend the turbo though for sure. Well, for a RB30 anyway. good luck, hope this helps. pete. Some original photos have not been recovered yet.

Found this info at another forum thanks to Warpspeed The great myth exposed ! A supercharger does indeed require power to drive it. The power required is actually mass airflow times boost. You also need to include the extra power required due to efficieny losses in the blower caused by heating of the air above that which occurs because of compression. Also belt drive losses need to be taken into account. If you do the maths you will probably find between ten and twenty percent of crankshaft power is lost driving the blower in a typical modern street engine. Now a turbo also requires power to drive it. The power developed by the exhaust turbine is once again mass airflow times boost, plus efficiency losses, plus bearing losses. If your supercharger has 70% adiabatic efficiency, and your turbo runs at about 70% adiabatic efficiency then the actual shaft horsepower required is going to be identical ! But to drive the exhaust turbine there must be a pressure drop across the exhaust housing and turbine wheel. This is basic thermodynamics. you cannot get power out of something without putting power in. If you have ever measured the pressure drop across the exhaust turbine you will find it will be typically betwwen twice boost pressure, down to the same as boost pressure if you are really lucky. But how does this extra back pressure in the exhaust manifold effect engine power ? Well again research has been done into this and the results have been published. Typically an engine looses 1% of crankshaft power for each psi of back pressure in the exhaust manifold. Surprise ! ! you are going to lose about ten to twenty percent of crankshaft power to drive your turbo, exactly the same as that required to drive a supercharger. Ah but if you loose 1% of power per psi that means at 100psi back pressure you would have no power at all ? Yes indeed. When the exhaust valve opens there may be roughly about 100psi left in the combustion chamber trying to get out. If there is no exhaust flow, the engine will stop. Hence zero output power. The myth that superchargers draw power from the crank, and turbos are free power for nothing is just that, a myth.

Thank you BlackVLGrpArep. I was also doing some page flipping to find this info, but you've said it well... so I don't need to. If anyone would like to do some research into this area, you'll be surprised at some of the really high efficiency ratings of some centrifugal superchargers on the market. Want proof that they can be just as powerful as turbos? Just check out Rob Vickery's ute, DCIEVE. Sure it's taken to the extreme, but he one horsepower heors 2000 with a single Vortech V7 blower. In 2001 he was beaten not by a turbo, but a Twin Turbo. In order to reclaim the crown, Rob went down the twin turbo path too. Due to geometrical restrictions, a twin supercharger setup is near, if not, impossibe. But the fact remains that the most poweful car in Australia with a single Charger on it was a supercharged car.

Although, that being said, if someone tuned a single turbo engine to the same power figures, methinks driveability would have been left at the door long ago.

Its not a myth, what it is saying is true but the turbo uses heat energy to drive it which is freely available through the exhaust process which occurs anyway. This article/post was obvioulsy a rebuttal to someones claim that a turbo takes nothing away from the engine to operate. As far as the blower efficiency loss is concerend, it all depends on the type of blower you are running. A cetrifugal blower will require less crank power to operate thatn a whopping big Weiand 6/71 roots blower. It is correct when it says you cant get something for nothing. Unless you have discovered perpetual motion in which case you would be rich. Turbo however are more effecient tha blowers as far as the whole power trade off is concernced.

Not true. Heat does not cause your turbine to spin.

BurgundyCalais, lets remeber that he is asking about an RB30 here, not a V8. Of course a V8 is going to respond well to a blower, its got more grunt to give in the first place. There is a blower kit for the RB30, I will try and find info cause its here on the site somewhere, or on R31skyline club. As far as your Blower V8 vs twin turbo argument. The bloke who came runner up in HP Heroes to TTV8 was a single turbo charged Torana.

No, the exhaust does but the turbine utilises the energy from the heat generated. Its why guys wrap those turbo beanies around the exhaust housing, cause turbos run more efficiently hot (the exhaust side that is).

i thought the exhaust gases spins the wheel in the exhuast manifold and that spins the compressor wheel not some heat wat ever ur talking about and there are different types of superchargers ones that the more revs the more boost while there are superchargers that allways run on the same psi sorry i cant remember the names of the superchargers ops: Some original photos have not been recovered yet.

Crusader is correct, There are superchargers (can't remember name either) that use a a sort of semi-clutch configuration that stops the belt spinning faster than a desired speed. This way it speeds up to a certain boost level, then holds. Sorry bout the vagueness of my description here, but it's late and i can't be stuffed looking for the tech details around here. The only reason turbo's run more efficiently on hot gas is because they're configured to do so. They're designed to operate at maximum efficiency with a certain volume of gas flowing through it. Hot air is more volumous (is that a word?) than cold air, and due to the natural tendency for a turbo's environment to heat up, they're configured to work best in these conditions. The heat itself doesn't lend power to the turbo in any way. Once again, sorry for vagueness, but yada yada yada... Quote: BurgundyCalais, lets remeber that he is asking about an RB30 here, not a V8. Of course a V8 is going to respond well to a blower, its got more grunt to give in the first place. thats why I said, Quote: Sure it's taken to the extreme But I don't really get what your on about anyway. If a v8 responds well to a blower 'cause its got more grunt, why then won't it respond well to a turbo? I can't see the logic in your argument. Finally, as far as HP heroes is concerned, 2002 lacked any real competition from blown engines. And who's to say the torana was particulalry driveable. If you expect me to believe that that thing doesn't suffer from the worst case of turbo lag, then you really underestimating my intellect.

I'm tired, excuse my poor punctuation, grammar, spelling, etc.

this was done done recently on performance forums here: http://board.performanceforums.com/forums/showthread.php?s=&threadid=67135613

Anyway im still wanting low end power for quick take off, and im guessing that if I wack in a stage 2 cam shaft, port + polish the head, trick the computer up, and wack on a small supercharge at around 7psi and all the other mods exhaust diff g/box blah blah blah......This thing mite actually go alright or not?

Quote: Originally Posted by BurgundyCalais If you expect me to believe that that thing doesn't suffer from the worst case of turbo lag, then you really underestimating my intellect. Im not slagging off on you or our knowledge mate. Im having trouble getting my point across. Its too hard for me to explain. I am trying to remember what the hell they call the energy released from the exhust gases that spins the turbine is called. My point is not going to make sense until I do. No offence but your arguement isnt making a hell of a lot of sense to me, it seems to have wandered from the original question quite a bit. In repsonse to the crusader diagram, I know how a turbo works. Quote: Originally Posted by BlackVLGrpArep Anyway im still wanting low end power for quick take off, and im guessing that if I wack in a stage 2 cam shaft, port + polish the head, trick the computer up, and wack on a small supercharge at around 7psi and all the other mods exhaust diff g/box blah blah blah......This thing mite actually go alright or not? Yes, that would go good especially from down low. Anyways BurgundyCalais Im not going to have a fight about this stuff, its not worth it. Have a nice day boys. Some original photos have not been recovered yet.

Yeah dude, i'm not in for a bash either... too many late nights getting to my responses!! I'm more than willing to let this debate go to someone who knows more about it than me, cause at the end of the day, all I can do is regurgitate **** that I've read... never had any first hand experience really. Cheers mate.

I think turbos are excellent for the simple fact that they turn wasted enery(exhaust gases) into more power. A great invention indeed. ...and they can be BOOSTED unlike a blower!

K here goes, made up my mind on wat im doin.... n/a rb30, 4agz blower or 1gg, stage 2 camshaft, VLT ecu and possibly VLT injectors. Normally they would attach the blower where the Aircon compressor would sit but i still want that, so they are moving the alternator up a bit and putting the blower underneath that. 4agz or 1gg $250 plus a recondition kit Stage 2 Waggott Cam $120 VLT ECU $150 VLT Injectors $50 each new Work and Fitting $500 so that works out 2 $1320 wat you all think?