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Does higher compression spool a turbo at a lower engine speed?

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Old 01-18-2012, 01:32 PM
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Default Does higher compression spool a turbo at a lower engine speed?

I think I might be confused but can't get my mind around where. I don't see how more compression spools a turbo at a lower engine speed. I think higher compression makes the engine rev faster which results in the engine getting to the threshold were it can spool the turbo faster. This means the turbo is spooling faster but not at a lower engine speed. The engine simply got to the speed at which it spools the turbo faster. Here is why I think this. What spools a turbo is flow through the turbine. Anything that makes the engine breath better at a given engine speed makes the turbo spool faster at that speed. Compression does not increase flow like other mods do. It makes the engine more efficient meaning it makes more power with the same flow through it.



In summary I think that more compression makes a turbo spool faster but not at a lower engine speed.
Old 01-18-2012, 02:23 PM
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You are getting a bigger bang as you said (more efficient) so your exhaust is pushing that same amount of air harder (higher psi), therefore spooling quicker. The only problem with high compression, is you are getting way too high cylinder pressures and that is how you break things. The beuty of a turbo is that it gives you much more power with only slightly higher cylinder pressure.



But I think you are confusing volume (or flow as you call it) and pressure, pressure spools the turbine, but when you have a closed system, with higher volume than can handle, the pressure increases, and that is why high rpm spools faster. But with the added pressure from the high CR, you will spool faster.....Will it be noticlably sooner like 200rpm or will it be more like 10rpm? I don't know, but it will be sooner.




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