Ok so im wondering why there are two turbos on our cars, when we get a full 10psi at 3Krpm..... what is the need for the second turbo? Im thinking its something to do with flow as opposed to a measurment in psi...

enlighten me!

thanks!

 

The turbos are tiny. Once turbo (of the stock FD turbo size), while it will spool quickly, won't provide a lot of power on its own.

http://www.autosportracetech.com/RX-...erOverview.htm

 

A good way to describe the the sequential system as explained to me before, is to look at the turbos like a water hose .

When you turn the water all the way on you get all the volume of water your going to get (10psi) put your thumb over the end of the hose and you have now increased the pressure of the water from the hose (2nd turbo kicking in) but not the volume of water.

 

i would think one turbo can flow 10 psi at 3000 rpm but could not at 5000rpm....
the second turbo is need to maintain that 10psi at the higher rpm range.

 

psi is a measure of pressure and not volume or flow. The higher the pressure the more flow you'll have through a given conduit. But increase the size of that conduit (garden house, turbo housing, etc) and less pressure is required to achieve the same amount of flow.

pressure x area (size of conduit) = flow <-- not a scientific equation

 

The simple answer to your question is: no single turbo can provide boost through the whole RPM range that the sequential twins do. It would either bog a lot down low or peter out up high.

Now with newer technologies like variable vane turbos that might not be as limiting, but in 92 that was the hard reality.

Dave

 

very good analogy