thank you very much for info jmac.thanks for link to the WBO2 gear.i will research this gas analysers.atleast this particular one is in OZ.Im using a12 as it came originally with vehicle and hoping to see track someday in future under 1300cc class thus choice of dcoe webers.Im a big fan of the TS spec sunnys in japan and love the a12 "revvyness".Otherwise i do agree the a15 would have better torque and hp and a cheaper way to extract power from as compared to a12.
As for engine life,how long would a 110bhp 7600rpm a12 engine last and what would need to be rebuilt when the times come?
I will for also look for the book by des hamil mate.
Im astonished by what one can learn by asking infor from helpful forum members.