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Does anyone know a book or a website where I can learn more about how to size turbos for the engine and the intended use?
I'm not planning on doing something unique, or arguing with well tried techniques, I'm just interested in how it all works. I could probably dig out some old fluid dynamics books and start working things out, but I'd prefer a more simple explanation if it's possible.
Essentially, the TD04 is an old turbo, turbo design and technology has moved on since it was first introduced.
My basic understanding is that a turbo too small will spool up very quickly, but run out of steam quickly, and a turbo too large will spool up very slowly so although you get more power, it will take an age to become available. A larger turbo will allow you to run higher boost, whereas a smaller turbo can't cope with big boost. New turbos such as the GTX supposedly allow you to run a bigger turbo than you would have been able to in the past and not suffer from major lag.
Above is the sort of statements banded about at meets, in the pub, and on forums, to me it would appear that the main KPI of a turbo system is how much boost it can produce, so sizing is a turbo is about how long it takes to get to your target PSI and how much of the rev range it can maintain it. How do you calculate that for a given engine and turbo?
I think we did this before but I can't find it.