This is Johns Guide to buying that perfect hairdryer for your car.

First you need to take stock of your goals, finance and current car.

Goals- how much power do you want, how much lag can you cope with(lag is the period between asking the engine a question, and the engine answering, and generally gets worse as larger turbochargers are used). 

Finance- If i need to explain this then you really should be doing something a bit more economical.

Current car-Is it already turbo or will you need to do a conversion? what else(drivetrain, ecu, brakes suspension) will need to be modified, how much labour will be required for the planned job,any major problems.

Once you got all of those under control its time to figure out what you need.

Get a turbo that will suit your requirmements. while that trust t88-34d may be going for a song, your 1.3 swift will probally be a little laggy:)  

Try to avoid the masses of chinese turbos flooding the place because while they are getting better all the time they are still a long way of the pace when compared to anything jap/usa/euro-if you must go budget look for the masterpower brazillian turbos, they have a reasonable reputation.

Learn to read a flowchart. The only way guaranteed way of actually knowing what the turbo your getting will do is to have a look at its flow chart . Rarely available with the turbo youll need to dig deep on the net to find these. Once you do get it you can work out when it willl make boost, the maximum power figure you can get out of it and how much boost you can generate at different engine rpm levels. Not the most elegant things to work with but a hell of a lot better than guessing.

After you have worked out all this have a look at what equivelant turbo's are going for. Whatever you do dont hurry in and buy thie first half reasonable half usefull turbo you see. Trust me the perfect turbo will show up soon.

 Now you know what you need, and what itll probally cost. All you have to do is hunt around until you find something that has either been badly advertised, or misadvertised or is a relative unknown swoop in and grab a bargain in confidence.

P.S If wank factor is your bag, then you probally dont really need to read this. HKS,Trust, and other turbos of that ilk demand a premium and you can usually find something that delivers 95% of the effect for30% of the profit.

rough turbo sizing guide for some common turbo specs

~2 Litres capacity: t25 and t28 framed garrets,IHI VF22's, many stock volvo and saab turbo's are designed around these capacity and work well in smaller engine turbo conversion.

~3 litres capacity: T3framed garrets, ihi rhc6's,

~ 4 litres capacity: T4 Garrets, T66's,

internally gated turbos are much easier to install than externally gated turbo's with less parts required and simpler manifolds, though they cant run as high boost levels.

Lpg makes great power in turbo set up, LPG injection is teh poo.

The two most important elements in a succesfull turbo swap/conversion are quality fabrication and intelligent tuning. skimp on either of these and pay for it later.

 Last but most important, have fun and learn as you go along, its the journey not the destination that provides lasting satisfaction.

boosting off into the twighlight

john :)