Superchargers and the GEMS

[Essarex]

With the present MPI setup, the GEMS is plumbed into the high pressure side of the system, right before the throttle bodies on the intercooler.

The boost gage, on the other hand, is plumbed behind the throttle body blades, in order to read true psi as seen in the cylinders.

If you can see where this is going, you would understand why these superchargers have less than desirable fueling and mpg performance. The GEMS is reading more boost than what the cylinders are seeing. Especially under part throttle situations. Like when you are cruising down a packed trail at speed, 70 mph. The rpm is high but the motor load is low, like 1/4 throttle. GEMS sees boost and the heads and boost gage see a big pressure loss across the almost closed throttle blades.

The GEMS won't live behind the throttle blades due to the vacuum produced under certain circumstances, BUT, what if we plumbed it there using a check valve to close when it sees vacuum? GEMS would then be protected from vacuum and would see the true pressure that is in the cylinders and therefore fuel accordingly?

Anybody ever try this?

 

[tjc]

how would the pressure lower with the check valve? for example the boost goes to 10 PSI then drops. The pressure in the tube between the check valve and the controller would not go down with the boost pressure. it will always read 10 psi. You need to be able to move air both ways i would think.

 

[Essarex]

Never thoought of that,,,,you're absolutely correct.

(this is the beauty of this forum)

Jim

 

[rxrider]

MCX uses a one-way-valve to keep their MAP sensor alive, the valve is closed under pressure and opens under vacuum protecting the sensor. The valve is installed just in front of the sensor.