1 reply to this topic

[PortlandJon]

I have just picked up an engine that I was told is stage three tuned but I have no idea what CC it is. There is no engine number, just the part number on the block. I have measured the bores and valves etc., details below.

Numbers on block

12A497 and B22K3

Bore 64.3mm

Numbers on pistons - M2039 x42

Head

Number 12G295

Inlet 31.8mm

Exhaust 29mm

I couldn't get an accurate measurement of the valve sizes as I couldn't get my callipers in very well.

Anything anyone can tell me about this would be useful and will help me to decide whether to sell it or use it.

Thanks

Jon

[62S]

12A 497 is a small bore block and 64.6mm is the bore for a 998 or 1098. You need to measure the stroke to determine which you have, the 998 is 76.2mm.

12G 295 is a 998 Cooper and/or MG 1100 cylinder head but normal valve sizes are 30.86mm and 25.4mm