What does dual stage mean?

FloydV

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I was reading about the RR Merlin engine developed in WWII. It had a two speed dual stage supercharger with inter-cooler.

I get the two speed. But what is dual stage? Also, P51's were authorized to go to 16+ pounds of boost for no more than 5 minutes in combat. How high a boost do you turbo guys run?
 
I'm betting dual stage is the same as the air compressor terms. The intake charge is compressed twice. It would be like mounting two turbos in series. Output of turbo #1 goes into the input of turbo # 2. I've seen some HD trucks with both turbo and roots style supercharger in this method.
 
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The US Army's M109 Howitzer is powered by a Detroit Desiel V-8 that has a huge turbo flowing into a big supercharger. It made a a really cool whine when on the throttle but it didn't go over 25 mph. (kinda like a lot of Ford products....)
 
I'm betting dual stage is the same as the air compressor terms. The intake charge is compressed twice. It would be like mounting two turbos in series. Output of turbo #1 goes into the input of turbo # 2. I've seen some HD trucks with both turbo and roots style supercharger in this method.

Sounds logical to me.
 
Not sure about what it means with the Merlin engine but here is what I think it is on my turbo. I run around on about 8lbs of boost with a spring, I have a XS boost controller that when I squeeze the flash to pass switch the wastegate stays closed until it hits 12 lbs of boost. AKA my 2 stage or dual stage or second stage of boost.

However my bike is still a stage 1 turbo bike run on FMU. Does this make sence?
 
Bingo! :beerchug: The compressed charge is feed from the first "stage" compressor into the second "stage" which multiples the compression of the intake charge. Often there are two very different sized compressors used to help reduce lag.

The term compressor could mean supercharger and/or turbo. Anything the can compress the ambient pressure.
I'm betting dual stage is the same as the air compressor terms. The intake charge is compressed twice. It would be like mounting two turbos in series. Output of turbo #1 goes into the input of turbo # 2. I've seen some HD trucks with both turbo and roots style supercharger in this method.

Turbo busa can run 40+psi but not with pump gas.
 
Bingo! :beerchug: The compressed charge is feed from the first "stage" compressor into the second "stage" which multiples the compression of the intake charge. Often there are two very different sized compressors used to help reduce lag.

The term compressor could mean supercharger and/or turbo. Anything the can compress the ambient pressure.


Turbo busa can run 40+psi but not with pump gas.

This makes a lot sense. Thanks.
 
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