DBT Engineering

Carburettors oval bored.

This is a job that I do on a regular basis for a local engine tuner. The idea is to bore the carb oval, which gives more top end without losing anything anywhere else, if you just bore the carb bigger diameter you lose at the bottom end.

34mm carb

The carb is only truly round down inside where the machining has been done, that is where I find the centre position of the carb.

With the boring head set at 34mm I move the machine 1mm towards the top of the carb.

Then bore though till the cut stops, you can't see it but you can hear it!

Stop the spindle and retract the tool making sure the cutting tool is positioned towards the bottom of the carb, that way there is no scratch left in the bore of the carb.

As you can see material has only been cut from the top side of the carb bore.

Job Done.