Hi John, you know the turbo bug is not a bug, it's one of those diseases that you never get over, especially after you've ridden or driven one that pushes 25 or 30 psi of boost...
The difference between systems is where the fuel gets put into the air stream. A blow -through does just that - it blows through a carburetor and puts it, as well as everything after it, under pressure. That is #1 = turbo, #2 = carb, #3 = manifold and engine. A suck-through places the carburetor in front of the turbo, as in #1 = carb, #2 = turbo, #3 = manifold and engine. Either system can use an intercooler after the turbo, but a suck-through will have major problems, so it's rare for one to be used.
As far as brands/models are concerned, that's not really a big consideration. You have to get one that is sized properly for the engine displacement, the power you want to make, the rpm operating range you want to use, and the engine characteristics. About the only real commonality you should look for is bearings on the shaft, not bushings, and a water cooled center housing. All center housings have a pressurized oil line to them and a gravity drain line, but not all are water cooled. If somebody tries to talk you into less than that, and you want to race it, you're asking for more expense down the road.
Ak Miller wrote a great book some years back, I don't know if HP Books still has it in print. He used a 230 and customized his exhaust manifold to bolt the turbo onto the top of the motor. A single Corvair side-draft carb on a suck-though system made about 275 horsepower (if I remember correctly) on an otherwise stock motor. I think he also used water injection to cool it down a little.
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David
newbie #4153
