LPG Mixer Ring Orientation

[Richard Kaye]

I am changing the LPG system on my 1988 Range Rover from an Impco 200 mixer to a ring style mixer, AT90E converter and a Gastec FP32 closed loop control. The mixer ring (pictured) has a flat side and an angled side, which way around does it go. is the flat side upstream or the angled side?

[FisherX]

That's a venturi so the angled side will face upstream towards the air filter.

[Richard Kaye]

I have tried the mixer ring in both directions. Seems to make little difference which way around it is.

[theelms66]

That's a venturi so the angled side will face upstream towards the air filter.X2

[FisherX]

I have tried the mixer ring in both directions. Seems to make little difference which way around it is.

The gas will come out under pressure so the venturi won't be needed at low loads it will come into effect on high load high rpm situations.

[Richard Kaye]

Thank you. From what you have said and from some documents on the mixer I have read, I need to put it in with the venturi side toward the air cleaner. I am going to try and install the closed loop system over the weekend.

[Richard Kaye]

I have the mixer in but have now ran into another problem. I can just get the car to (just) idle only if the high speed valve in the LPG line from the converter to mixer is completely closed all the way. The air/fuel gauge in the car shows even with this all the way in its extremely rich. With the setting in this position the car will only rev to around 2000rpm then it runs out of LPG. I have tried 2 mixers an OMVL and a BRC both do the same. Am I missing something?

[Richard Kaye]

I did away with the mixer ring and installed a BLOS. With the O2 sensor I have been able to tune the BLOS, which is between the throttle body and AFM, and it is now running very well.
The Impco 200 which I had previously could manage around 22 litres per 100km, with the BLOS I have more power and its returning 17 litres per 100km.
I have a K&N air filter coming and a set of headers, interesting to see how the car goes with these on.

[Blknight.aus]

I did away with the mixer ring and installed a BLOS. With the O2 sensor I have been able to tune the BLOS, which is between the throttle body and AFM, and it is now running very well.
The Impco 200 which I had previously could manage around 22 litres per 100km, with the BLOS I have more power and its returning 17 litres per 100km.
I have a K&N air filter Strainer coming and a set of headers, interesting to see how the car goes with these on.

Fixed it for you

I'd probably suggest you're going to be better of with an OEM filter