converter slippage

Just got back from battle of the brands at hpt Topeka. Ran a 10.53 at 126.54 tonight was test and tune. Any way my torque converter slippage came out to 10% down from the 16% I figured in the 1/8 mile. With the 4.30s I am at 6800 at the stripe. So about perfect. Didn't hurt my 1/8 mile times with the 4.56s so I am pleased. I am at a loss but that's OK it worked out well.