hello folks, i was wondering if someone could enlighten me as to which engine i have, it carries the following marks. Cast on top ak84m 650 and stamped on the flange the number 9743356 thanks in anticipation.

Hi David,
It will be a 652cc engine from either a Fiat 126 or a Niki (FSM) 650 and likely the 9,743,356th built. These engines in one form or another were built through until around 1992.
Chris

many thanks never heard of a Niki , eastern european at a guess

davidboris said:

hello folks, i was wondering if someone could enlighten me as to which engine i have, it carries the following marks. Cast on top ak84m 650 and stamped on the flange the number 9743356 thanks in anticipation.

Click to expand...

Hi David , what you have there is one of the later 126 engines with the unleaded cylinder head , improved combustion chambers and higher compression ratio so they had a slight power increase on the earlier 650 engines so if it is in good condition you have done well there. I have just this minute got back from the post office sending off one of those new heads to a specialist to be ported/gas flowed after I had already had larger inlet valves fitted. The original 650 heads just have the 650 on the casting.

For FSM see - https://en.wikipedia.org/wiki/Fabryka_Samochodów_Małolitrażowych

This is what I did with my 650 head - big valves (34mm intake and 29mm exhaust) as well as the usual porting and polishing.

Chris