Very NICE!!! I like it a LOT!!

Oh and BTW guys a lot, probably most of the air volume will still be going thought the blower its self, just not compounding or building more pressure because the by-pass is open neutralizing the air pressure between the pre and post blower chambers. Very clever.

 

very cool man. i bet having the blower makes the turbo spool really quick too like if you were to hit it with nitrous. interested in seeing how it works out for you. you have the ability to run tons of boost with good street manners im sure.

 

That was the idea, streetability with the potential for a lot of quick power The turbo does spool pretty fast because the blower gives it the extra push that it needs to get moving. Once the turbo is making boost, the blower goes into bypass and the turbo is left to work on its own.
I'm just pleased the my little boost manager works like it should. In this whole project, that was the only thing that I was concerned about not working correctly. But you can watch the gauges (now you know why I have two, to who ever asked before lol) and it's easy to see when the blower gets bypassed and it goes all turbo.
My main reason for doing it this way and not like the regular compounds is the parasitic drag of the blower. When the blower is forcing air that is already compressed into the engine and further increasing boost, parasitic drag is enormous. Even running a ton of boost on a compound setup, it'll never keep up with a turbo alone at the same boost level.

 

So you really tweak when it changes from blower to turbo by the ratio of pulley size and turbo wastegate, with the later controlling max boost as well?

 

WOW!! that's really cool and way to be original!! At what RPM or psi do you have the switch over take place? I don't know enough about these blowers to be able to visualize how the airflow is directed but I kinda understand what ya did. So what happens when the TB closes after a WOT spurt?

 

If im thinking right, the bypass valve on the blower will be open, and the wastegate will do its thing, so it works just look it should in both cases.

 

I control the switch from blower to turbo with the little boost manager I made. I just dial it in to whatever boost level I want, depending on engine size and capability.

The switch over is set to 3.5psi. Once the turbo reaches that pressure, it goes solo. After the throttle body closes on a turbo-boosted WOT acceleration where the bypass is open, the BOV opens like normal...the bypass then sees the vacuum reference (same one BOV is on) from behind the throttle body, which keeps the bypass open.

 

Oh so you are not using just vacuum to actuate the bypass valve, but are using your own controller? How does that work if you dont mind me asking? Wouldnt the max potential boost of the blower still be pulley dependent?

Only thing im skeptical about is the flow of that blower bypass valve....I remember looking on mine on my magnacharger and it wasnt that big, not sure if the rousch one is larger. When you say 9psi at 6k rpm, is that blower rpm or crank rpm, and if crank, what size pulley was used? Just off the top of my head I know the tvs1900 at 15k blower rpm moves right around 1000cfm.

 

The blower is still flowing air through the rotors, the bypass is just equalizing pressure on both sides of the rotors, allowing for a whole lot less parasitic drag, and lots more top end power.

 

Maybe im still missing something but wouldnt there be flow reversion if thats the case? The pressure after the blower is greater than before so air would go backwards through the bypass valve since the pressure of turbo + blower is more than blower alone... or is the blower not able to flow enough at higher rpm to make positive pressure?