impco 200a

[Andrewh66]

Hi all

I have a 92 TB42 efi auto on LPG

It has the impco 200a system on it which is a big improvement on what it had on it.
Tuning it is a problem I had a dud feedback valve I have replaced with a new one and it is much better now,
When I put my air\fuel gage on the car I can get the idle mixture good but once i open the throttle it will run rich and pulse back towards lean but is off the scale rich I have added leaning rings which only seams to lean out the idle and I have also changed the power valve position with it set to lean it still runs rich off the scale but with a slight flat spot,
So when I am driving at 80 kph I get to a small hill or I want to speed up without flooring it.
It is like it has a flat spot \low on torque un till I get the rpms to about 3,000.
And the other week the back door wasn’t shut properly and it smelt very rich
The economy on LPG is worse than the old system which ran quite badly now I am getting 360klm from 97lt and I was getting 420klm from the 97lt.
I am happy for it to use gas as it’s a big car ,auto and shaped like a brick if it went well no flat spots I would gladly not worry about a few klms less out a tank .

So has anyone had problems like this on their patrol??
Do I have to change the gas valve that the diafgram bolts too for a slightly leaner one or do put a 425 mixer on it will I have to keep the feedback valve set up and will the type L converter be able to keep up with the 425


Thanks

[cliff]

I had the same problem and it turned out to be the butterfly in the throttle was a little bent. There are plenty of good gas guys there in VIC take it to someone that knows their stuff and get there opinion.

[Andrewh66]

I had the same problem and it turned out to be the butterfly in the throttle was a little bent. There are plenty of good gas guys there in VIC take it to someone that knows their stuff and get there opinion.

so where are the good gas guys in the northen suburbs???

[cliff]

I'm sure there is a gas research buy around thomastown, I think, its been a while. I'll ask my cousin he's more in the know about that now and I'll get back to you.