I'd deffo do it, but I'm very dubious as to how simple exaxtly this is...
Like you say, you would need an oil feed return for the turbo, and if you are right about the management, you might get away with a remap rather than standalone, but what about:
-Injectors (will the standard ones cope?)
-Spark plugs (surely you'd need ones for turbo applications)
-Intercooler (very wise if you are going for a turbo, even on a low boost application)
-Map sesnor (your map sensor probably wont be able to cope with the amount of air pressure in the inlet, and will give very odd signals to the ECU)
-Oil cooler (also very wise)
-Downpipe (you'd need one but probably easy if you've got the turbo and manifold)
Did the Saabs all use manifolds like the one above? Looks like a log manifold.. I'm sure all of the parts above could be sourced off a donor engine, but think about how the boost will run with your current Modifications.. Are you running STD or uprated cams, etc..
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