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The turbos spool up to whatever they can nothing limits them, the boost is controlled through the watesgates by releasing pressure to keep the desired boost.

So as mentioned the boost is measured at the manifold and the controller takes that input and opens or keep the wastegates closed to attain and maintain the desired boost.
 

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Discussion Starter · #8 ·
Okay here is a detailed description of everything i am trying to run.

Stock VQ35 motor
Greddy twin (18g) turbo kit
NO intercooler
Directly bolted on
NO boost controller
2 Greddy Type S wastegates(38mm). with .8-1.0 spring in each (right??)

that being measured, its 11 psi to EACH turbo. 2 turbos = 11 + 11 = 22 psi?? or 11?? i have no boost controller so im running directory off of the e-manage and wastegate spring.
 

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5psi in 1 pipe + 5psi in another pipe dumping into the same manifold yields 5psi.

Think of it this way... if you have two glasses of 50º water, and pour them both into one big glass, the water is still going to be 50º, not 100.
 

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ouch...tough crowd. :)

If you put a 5lb spring in both wastegates on a greddy kit, you end up with 5psi in the manifold (subtract a little for intercooler looses).

I think the question are you asking has more to do with the MASS of airflow, rather than pressure. Remember that turbos do not create pressure, per se....they create a mass of airflow. Pressure can vary based on ambient conditions, but the key measure is how much airflow the turbos are creating.

For instance, lets make an assumption that 30lb/min of air is needed to create 10psi of pressure in the manfiold. In this example, each turbo is supplying rouhgly 15lb/min worth of air. Each turbo is contributing half of the airflow into the engine.
 

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+1 on Sharif's post above, it is the mass air flow that the turbos are sharing. They each produce half the air flow.

The pressure is equal for both of them when they meet in the intake manifold.
 
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