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I've been recently reading up on the differences of between turbochargers and superchargers - interesting read I must say ;)

Now this question occurred in my mind:

Is it possible to stick both a turbocharger and supercharger into a twin turbo car (let say an R32 GTR 'cause I love them)?

If it were possible what would the benefits be?

Seeing as there would be turbo lag, would the installed supercharger cover for that initially (and once it kicks in, ;))?

Sorry, if a similar question was posted. I was too intrigued my hand couldn't stop typing :D

Thanks in advance.

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stockymystock has an rb30 turbocharged and superchareged

can be done, costs lots of $$$, lots of custom work and changes

twin turbo is easier, cheaper, more normal

a good twin turbo setup would negate the require for super & turbo

as it would provide good average power, remember superchargers suck some power to give some power

its not like its free

sure a supercharger needs crank hp to run, but since it creates boost as soon as it starts turning, and feeds it straight back into the engine to create more power, the hp needed to run the sc is then accounted for. feedback cycle.

eg. engine 100hp

sc 50hp

sc boost power gain 100hp

total hp when you use the engine with sc = 100 - 50 + 100 = 150hp. net increase in power even though the sc takes 50hp, it gives back more almost immediately.

the energy is supplied by the additional fuel burnt as a result of the increased intake charge pressure. you wont experience any 'lag' from a supercharger

the power is not free, you pay for it in fuel. but you dont 'lose' any power from having a sc

if you can do fab work yourself and have the mechanical knowledge, it can be a cost effective option

of course it takes a specific application to require a super/turbo combination.

in track, drag, or most race applications, low end driveablity and torque down low is not usually a factor as gearing and driver skill is used to keep the revs in the powerband (top end of the rev range).

twincharging can be done relatively cheaply using aftermarket parts such as toyota factory superchargers.

unless you want something different there is probably an easier solution to lack of low end torque with a large turbo.

i would suggest a good ecu setup with anti-lag and the use of cheap t3/t4 based turbo chargers (as you'll probably have to replace it once in a while depending on your use of the anti lag).

or nitrous

Is it possible to stick both a turbocharger and supercharger into a twin turbo car (let say an R32 GTR 'cause I love them)?

Sure. There are a couple of aftermarket cars that have been twincharged, and Volkswagen has a production one.

Benefits are no lag at low RPM while getting more power down low thanks to the supercharger, and at high RPM you can enjoy the better efficiencies of a turbocharger.

The problem is getting it all to work together smoothly.

try looking at the twincharged s15 on youtube; was a fantastic watch and the results were fantastic.

sr20 yes but there was almost no lag so on an rb26 i doubt there would be any

are there any superchargers that disengage at a certain rpm???

So do turbochargers.

Technically yes, but in practice: they're sucking energy from waste gasses that are just being ejected out of the car anyway.

They do cause restriction, yes. but they don't suck raw shaft engine power

I believe the superchargers on the 4agze does that.It has a clutch on the blower drive much like an ac clutch

Yep.

I'm pretty sure the supercharged Merc engines have them as well.

They do cause restriction, yes. but they don't suck raw shaft engine power

And that restriction causes pumping losses. Stick a restriction in your exhaust, and see what happens to your power output. It's irrelevant whether that power "loss" has come from something attached to the crank, or something stuck in the exhaust. A power drop caused by an induction charger is still a power drop.

Its misleading to say superchargers "draw power to make power" as a pro against turbochargers, because the latter does the exact same thing.

Turbochargers are more efficient because they draw less power to give the same gain, but its not the free lunch some people make it out to be.

Edited by scathing

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