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i was wondering if the psi matters in turbos like if u use a t25 on 5 pounds would a t/3 t/4 turbo on 5 pounds would the t3 t4 push out more pressure at 5 pounds when the t25 thanks:hammer:
 

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PSI is PSI, that is the pressure so no, 5 psi is the same as 5 psi. However the size of the turbo decides how much airflow there is for that 5 psi. So a bigger turbo flows more air, and makes more power. You also need to know what size t3/t4 cuz there are many different sizes. SEARCH, this is all explained many times over.
 

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yes it makes all the difference in the world . just do some searching, 10 psi on a t25 would completely different from 10psi on a t3/4
 

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will it does matter when a t3/t4 has better top end power than the t25 would ever wish it had. but its about the turbo and your application more than the difference in psi
 

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NO it still pushes the same psi. Psi is a measure of pressure... The engine would be put under more of a load though because there would be more air flow and hence more power and more load on the rods, pistons, crank, bearings, head everything.
 

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ok listen up spanky,
5 psi ( pounds per square inch ) on a t25 is the same air pressure as 5 psi on a t3/t4 hybrid turbo.
the real difference is in volume of air or cfm ( cubic feet per minute ).
yes a t25 will make less power on 5 psi than a t3/t4 because it isnt pushing as much volume of air ( remember cfm? )
psi means nothing and is the ultimate noob question.
you need to read up the stickies.
 

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ok listen up spanky,
5 psi ( pounds per square inch ) on a t25 is the same air pressure as 5 psi on a t3/t4 hybrid turbo.
the real difference is in volume of air or cfm ( cubic feet per minute ).
yes a t25 will make less power on 5 psi than a t3/t4 because it isnt pushing as much volume of air ( remember cfm? )
psi means nothing and is the ultimate noob question.
you need to read up the stickies.
:thehump: straight to the point.
 

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a the only difference in performance is with a larger turbo it has to spool less for the same psi so there is less heat transfer so it's more reliable
 

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i think there is more to it than the cfm flow of the 2 different turbos.

air temperature and turbine size have a large effect on power output.
true, there are many variables to determine the efficiency of a turbo.
what really makes a difference is the DENSITY RATIO.
a turbo can shove only so much air into a cubic inch before the ratio of compression becomes inefficient and causes air temperatures to rise. the hot air tends to expand more outwards after this point and needs to work harder to reach its goal.
different turbos have variable density ratios.
the variable between
1. pressure ratio,
atmospheric pressure 14.7 + boost pressure or psi = pressure ratio.
running 10 psi is a pressure ratio of 24.7 dawg:eek:

2. density ratio as i stated above.

3. airflow rate,
CFM

put all these together and you have your compressor efficiency map.
remember these can all vary depending on the motor, tunning, and altitude.
:beer:
thats all folks
 

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again, it all depends on what you want. t3/t4 will have a longer spool time and more hp/psi. while a t25 will spool faster, but have less hp/psi. from what ive been seeing, ~10psi is safe for a well maintained D series motor, and the relability of your setup is all in the tune.
 
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