Carby / head port diameter question.

Am working through puting the top end of the engine together, I have:

A combat 750 head, 32 od mm ports,
A pair of Amal 930's ( 30 odd mm ports ).

What's the go, will there be issues when it is running ?.

Josh Cox said:

Am working through puting the top end of the engine together, I have:

A combat 750 head, 32 od mm ports,
A pair of Amal 930's ( 30 odd mm ports ).

What's the go, will there be issues when it is running ?.

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No! An un-noticable effect of being detuned is considered desirable by some.
Unless you are running a hotter than stock cam, consider a compression plate.

30 mm carbs will be more pleasant down low to mid range response only loosing some maxed out rpm power like maybe after 110 mph or so. I'd prefer 30mm carbs for normal sane not go to jail with speeding tickets all around use. Good response tends to do that. Accidental experiment of leaving a lip at carb manifold worked out great so I'd not bother to feather that area unless trying for top end rpm power. Diddle float levels so air screw best idle lands pretty darn near 1.5 turns out, then rest of the dial in has correct base line fueling.

If the 30mm Amals are OK and you want 32mm just bore them out to 32mm and rejet

Cash