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Discussion Starter #1
Well there's been some discussion of different turbos over in the 9-5 performance forum. Which ones offer the performance desired with the least lag on so on. Anyway, searching on the internet has turned up compressor maps and I have no idea how to read one of these. Could someone knowledgable give me the run down on these? :)

Thanks.
 

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Check here:

http://www.turbotechnics.com/products.htm#TURBOCHARGERS

But, generally, the turbine map shows the 'lag' as follows:


The 'perfect' no-lag turbo would have a perfectly horizontal line -- that is, it would be operating at max pressure ratio all of the time. The amount of the curve that is lower than the horizontal max represents the amount of lag.

For the compressor section, you're mapping the compressor section's ability to provide additional air mass to the engine, so ....



you'll want this graph to stand as vertically as possible -- that is, constant air flow even though the pressure (remember the other graph?) varies. If it isn't vertical, you want high output -- in this case, the farther right the better.

The amount of turbine lag and compressor curve 'lean' if you will combine to creat what we feel as turbo lag.

Of course, it's more complex than that, because there are efficiency bands on these graphs, as well as air volume information, but those are the basics.

Hope this helps.

Corrections are welcome.
 

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Discussion Starter #3
That's helped a great deal, while it's not everything I at least know basic what I'm looking at. Many thanks. :cheesy:
 
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