SUPERCHARGING

[motoboy]

im new to this stuff n i want to know wat does supercharging do and is it expense to do to a gemini.
if anyone can tell me ill be greatfull ive tryed searching but cant find anything some pictures would help but i really want to no is wat do u do any how n how much. thanx

[Benjamin]

Supercharging runs a mechanically driven pump, in turn forcing more air into the engine. Boost increases proportional to engine RPM. Turbos use engine exhaust to spool up a pump.

Advantages of supercharging are:
- less heat generated by pump (compared to turbo)
- no lag, more responsive
- greater torque and midrange (grunt)
- slightly less complicated
- no poofy BOV 'pssshhht', better sound

Disadvantages
- engine power used to drive pump
- supercharging limits engine revs, boost increases with RPM

It can be as expensive or as simple as you wish. Toyota 4AGZE superchargers (8-9psi) can be had for less than $400, so in theory you could mount a carby to one side of that, get some custom plumbing and you would be motoring for well under $1000. That is assuming your engine is modded to handle boost.

On the other hand (as I am planning), you can get the 1AGZE which pumps out around 12psi+, go for a 3D (or 2D) computer, run an EFI setup and go the whole hog, resulting in estimated 200hp easy for about $5000.

Anyone else got thoughts. I am considering doing this myself in the near future. Already sourced me a G200

[YLD GEM]

what sort of mods would ya have to do for the engine to be able to handle the extra boost??? And does anyone have an in depth article on fitting a 4AGZE to a G200? or know how to do it (or done it) and how much work is involved??

Thanx heaps

[Benjamin]

The standard bottom end should be fine. Fit a decompression plate as the turbo boys do and make sure the engine is in reasonable condition. If you are worried about the engine, you can back off the boost by fitting a smaller crank pulley and under-driving the blower for 6-7psi max.

The two blowers are:
4AGZE : SC12 : lower boost
1AGZE : SC14 : higher boost

To fit a supercharger in simplest terms:
1) remove carby and junk (retain standard inlet manifold)
2) fit decompression plate
3) mount supercharger to engine via some strong brackets on the exhaust side of engine (dizzy and other bits get in way on inlet side)
4) rig up pulley system
5) get a custom pipe made that runs from the supercharger straight into the standard inlet manifold
6) mount a side-draught Weber to the supercharger
7) make sure the fuel pump pumps more
richen the Weber up
9) fettle the timing a bit
10) voila!

Bear in mind I have written this with a bit of a sense of humour. It isn't that simple, I haven't done it yet myself
Sounds simple though eh? I have seen minis supercharged with very little effort so I can't see why putting an SC12 on a Gemini can be much harder. Mind you, if you want something really top notch then you should start with a fresh piece of paper and go all-out.

Cheers

[YLD GEM]

thanks mate. Still wanting to hear from somebody that has actually done it as I am woriied about the cost?
??