Thread: Anyone with knowledge re: impco 300a system?

I disliked them when I had to fit/service/tune them years ago, I wouldn't willingly fit one now. They can be very stable when new, but when fitted to an offset adaptor are very likely to stall under on-off idle foot movements. The idle mixture adjustment is very touchy, 1/8 of a turn can put it right out. Sometimes the screws holding the diaphragm to the centre piston fall out, that's fun too.

There is much better stuff around on ebay, a suggestion is a new gen mixer and OMVL converter. These are now so commonly sold I hardly bother bidding on them. No too many 4 barrel conversions happening any more.

thanks for the reply bee utey. when you say a new gen mixer could be a bit more specific please. i'd like to stay duel fuel for the range. do i take off the holley? The reason i used the 4 barrel was because it bolted straight to the manifold & i wanted to avoid any clearance issues.
regards, adam

Originally Posted by ahud7844

thanks for the reply bee utey. when you say a new gen mixer could be a bit more specific please. i'd like to stay duel fuel for the range. do i take off the holley? The reason i used the 4 barrel was because it bolted straight to the manifold & i wanted to avoid any clearance issues.
regards, adam

I haven't got any new gen pics on my laptop but a quick gargle search brought up this:

Google Image Result for http://www.teamgreenautogas.com.au/Image/Conversions/Petrol%20-%201978%20Ford%20Fairlane%205Lt%20V8/Petrol%20-%201978%20Ford%20Fairlane%205Lt%20V8Venturi%20Syst em%20-%20New%20Gen%20Mixer.jpg

They fit on top of Holleys with miminal height and are very good on petrol because of the air plate design which is vacuum lifted on petrol. I modify them slightly to improve their efficiency. My 2 door RR ute has one and it fits nicely.

I have a few spare and could possibly mod one for you after Easter. PM me if you are interested.

Sometimes I modify the 300A adaptors into a fixed opening mixer as in this pic of a WB Holden:



I de-gut the 300A head and fit a slotted LPG inlet tube through the cast adaptor. Not hard to do.