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I started a thread about this a while back, should still be around, alot of the info you will require is already in it. Tittled "supercharging" (i think, or supercharger or something like that)

Search is your friend :(

Its in the N/A section to

in my humble opinion, supercharging is for cars with enough torque to wind the pulley around with little loss of power, something like a v8 or large 6 cylinder.

Thats just my humble opinion, u do know u can still get lag on a supercharger setup, depends what sort of s/c you put on ... blah blah blah.

Oh and boost is measured differently i think, like 7psi on a turbo is different boost than 7psi on a s/c

boost is always and is measured the same, but a blower doesnt make full boost until it reaches max revs or is wastegated... which apparently doesnt work very well but im going to find out for myself.

That depends on if you're talking about a Roots-type supercharger, or a centrifugal one.

A Roots-type is always at max boost. Driving a car with one just feels like driving a large capacity motor. There's little to no lag on these ones, but because they're "always on" it means you're always boosting. Those ones tend to be measured in litres of air, rather than PSI.

The 4AG and Mercedes ones have a clutch so the SC can be disengaged for fuel economy reasons, but I don't know if you can get that kind of setup in kits.

The centrifugal ones need to build revs (since its basically a turbo compressor, but powered from the crank instead of an exhaust impeller) to generate boost, and those ones have various compromises.

Whats the point of spending soo much money supercharging an N/A when a stock r33 gts-t would still be more powerful...

Ive seen dyno results for a Supercharged N/A. Its just about being different.

NA_R33's case is much different, but for an rb25de, its not worth it.

Whats the point of spending soo much money supercharging an N/A when a stock r33 gts-t would still be more powerful...

Ive seen dyno results for a Supercharged N/A. Its just about being different.

NA_R33's case is much different, but for an rb25de, its not worth it.

Have anyone got any pic of their super-charged RB25DE???? :(

i've heard of it being done with mixed results, i have yet to actually see a supercharged rb25de or rb20de. I reckon it'd be faster than a gts-t to a point; it would hit boost sooner. As i understand it a sc would give power linearly and a turbo gives it exponentially.

As i understand it a sc would give power linearly and a turbo gives it exponentially.

Depends on the setup and type. A roots type blower will give you a very linear power increase (it'll just feel like a big capacity engine).

With a turbo or centrifugal supercharger its a bit more awkward. If you make the right compressor choice the power delivery can be smooth, but not quite as linear as a roots blower.

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