Secondary Main Well bleed tubes

[novadude]

Can someone explain to me the effect these have on the fuel curve?  I notice that Cliff's recipies often recommend sizing these to 0.036" regardless of metering rod.  How much does the bleed hole affect secondary metering?

[Cliff Ruggles]

The effect is minimal but does have an impact.  .036" tubes work well with metering rods in the .040-.055" range, but primary jetting also has some effect on overall A/F at WOT. 

Some airhorns will have an additional set of bleeds drilled next to the tubes, if they are left open leave the tubes at the stock size.....Cliff