Thread: Turbo Boost PSI
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      08-28-2011, 04:59 PM   #31
1SerieStud
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Quote:
Originally Posted by nachob View Post
This is the danger of throwing numbers around out of context. Most Turbo motors in the past ran 8:0 - 8.5:1 compression ratios to prevent detonation. Modern motors with direct injection like the 1M run 10:1 compression ratios. So you see, 12 lbs of boost with such a high compression ratio is actually a TON OF BOOST.

12 lbs of boost on your VR4 or SRT4 running 10.1 compression on 91 Octane gas would not have been pretty.

That is the reason boost in now controlled more carefully than before. The motors are running leaner, higher compression and higher revs.
Finally someone has typed something worth reading

Most people talk about boost without taking into consideration what you explained above (compression ratio), and very importantly, size of the turbo(s). Lower boost with a large turbo may easily translate to much more power than higher boost with a smaller turbo - here we enter the subject of cfm's.
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