Can I get someone with powerbomb to measure the headpipe OD

I need to know the diameter of the head pipe , before the bomb section.

Thanks

Before the PowerBomb = 34.5mm / 1.358"

PowerBomb = 54.21mm / 2.134"

Measured with a digital caliper.

Thanks, Thumper Racing told me they got better results on their big bore dyno runs with the stock head pipe.
I was curious why. The power bomb is actually smaller initially. Might be good for torque on a stock engine.