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Old 12-25-2008, 12:43 PM   #1
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Exclamation Turbo AR's Q&A.....

I've been noticing when people ask about what size turbo's they need they alway ask "do I need a .50 ar or 64ar" and so on....

The AR is nothing more than the size of the exhaust houing.... not the power capabilities of the turbo itself.

When looking at how much power you want to make you need to look at PPM (air in pounds per minute of flow)... a really neat trick I've picked up on is 1 ppm is good for around 10hp (rating wise)

Example a a turbo that flows 35 PPM is capable of 350hp ... according to how they rate turbos.

After you figure out how much FLOW you need then you need to look at AR... a smaller ar (example a .50ar) will spool faster than say a larger (.86ar) BUT usually the smaller ar will peak then start to fall off powerwise, the larger ar may take a little longer to spool but it will make more top end power. Also you need to remember that the ar is also a restriction... all of your exhaust has to flow through it.

* This is just some basic info you need to think about when looking for a turbo... there are also many other factors that come into play like the ratio between the hot side wheel and the cold side wheel.*

Any questions I can help you guys with???

[B]1951 McCormick FARMALL M
2007 MINI Cooper S Turbo... new project car
1998 Chevy 3500 Ext cab, long bed, 4x4, duelly, turbo diesel
2004 Harley V-Rod.... sex on wheels
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