Hi there,
With an 11.5ms time constant that means that the wave looks approximately like a straight line from some max to about one third of max. That means
that roughly for half that time (about 6ms) the wave is above two thirds of max and the other half of the time it is below two thirds of max. That puts the
average at about two thirds of max, or about 0.66 of whatever the peak current is. That basically means you do not get the full current over that time
period but a sort of average of two thirds of max approximately.
It sounds like you might have it right at 1.6 amps peak, if that's what it really is, but it's a good idea to go by the old saying,
"One test is worth a thousand expert opinions".