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Adding a 2nd MAF?



My engineering degree is in electronics not mechanical engineering. If you want to see my projects then take a read at my members ride page. If you would like to see some of my custom work look on Booba5185's page at the end for the throttle body I did for him. Look on the SCCOA for other projects I've done under my screen name here.

Im just trying to understand your rational on how you are going to make this work even SD. That's all I'm just trying to figure out what most of the rest of us see as issues.
 
What happens when you blow a fan into a fan both blowing at the same speed? The second fan changes the direction of the air driven from the first fan. Now put them into a box with a vacuum sucking air the same direction as the second fan.

Engines are vacuums. With ported heads, bigger valves, and free flowing exhaust it would devour the boost. It's not like it's a closed box with nowhere for the air to go.


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But the fans will not blow at the same speed, especially considering one is driven by a belt from the crank, spinning at the same speed proportional to the crank...

While the other is variable to the speed of the exhaust, and changes with both acceleration, deceleration, and even when the engine speed is constant, it will still change its speed, by either spooling up or slowing down, because of the nature of the design.

If you had said centrifugal supercharger, this idea would have a plausibility to it that others would be able to see clearly. With two separate drive systems for each boost producer, one being fixed and one being variable, there is a differential pressure created by that variance. Thus it will attempt to move to the area of lower pressure,

At any time that the intake and exhaust valves are both closed, the vacuum inside the intake will be sealed, and it will become a pressure vessel. Even for that small micro second, things will break at those pressure levels.
 
I am picturing 2 desk fans pointed at each other and what would happen is that the air will move out perpendicular and radially to the normal flow of a fan. Now if the box is the plenum and the fans are cut into it you are basically describing a twin turbo setup. The problem here is that you don't have 2 fans you have a fan and a pump, both of which have different characteristics. So now that you are not dealing with the MAF issue and it's SD. So how do you control the valve that keeps the supercharger from blowing air back through the turbocharger? You are going to have to dump the turbo air to atmosphere in order to get it to spool. A deadheaded turbo will not build pressure because it cannot gain speed, it doesn't matter that there is more exhaust production or not it will only spin so fast and depending on the boost from the supercharger and the size of the valve the amount of pressure is going to be very high, way higher than the boost pressure. If you had 15 psi out of the supercharger with a valve that had 2 square inches area on it the pressure is going to be 30 psi so then you need to have a 2 way valve that is controlled by some other function so that it vents the turbo and allows it to spool then closes and routes it into the manifold. But then again if the turbo is making more boost then it starts making the supercharger harder to turn.
 
yeah you would not want a turbocharger with a compressor stall/surge condition for long but you would also not want it vented to atmosphere either as you would be in danger of overspining it
 


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