finally got my car on the road wont go above 60 or the higer end of the rev range without spluttering and kangaroing
bottom end of revs runs fine. there are no air leaks the carbs bolted down fine and the float level is good. i got the car as a non runner though. (hole in float) could it be a wrong mixture? running to lean perhaps on the higher revs?

its a 1.4 on the downdraft weber

Yes you could be running a bit to lean if everything else is fine. Partial blockage in a jet or filter or poorly functioning fuel pump are also possibilities. A small air leak in a fuel line could also give problems when wanting more power.
Another possibility but rare is the filter on end of the pick up tube in the tank is crushing and cutting off fuel supply, had this happen on 2 other cars.

cheers ive now got to look up where to adjust the mixture will check that pipe tonite though thanks for the info

minimaniacwhyard wrote:finally got my car on the road wont go above 60 or the higer end of the rev range without spluttering and kangaroing
bottom end of revs runs fine.

Similar problem, runs fine on petrol and LPG up to 3150 rpm then sputtering occur.
But when I disconnect vacuum advance from Renix ignition unit the problem dissapears completely.

No leak, plugs good almost new (NGK ZGR5B), consumption ok, no other problems.
Renix is type 412A,
340 B14.4O , 1987 year, about 190.000km.

Any idea ?

sounds like you could have the wrong mixture or partially blocked jet. also i would be inclined to check the dizzy cap and rotar arm they do have a tendancy to mess up. i have a friend that worked on these when they were new and he said he had no end of them.

You are right, mixture was too fat and after adjusting LPG system it is a lot better no for the last two days..
But there is still misfire and place for improving mixture regulation.
Thanks for tip.