[comptiger5000]

RobertSmalls - With smaller engines, the effect is less significant, and friction/windage, etc contribute a greater proportion of the engine braking effect. In my Jeep, it doesn't get a ton of braking on downshifts at first. Then, after 1 - 2 seconds when DFCO cuts in and the IAC closes, it's like someone slammed on the brakes (big engine gives lots of engine braking).

It also depends on the cam setup, etc of the engine. Some simply provide more braking than others. For example, the engine braking in my sister's 94 Camry 4 cyl is pretty strong, but dad's 05 Camry V6 has much weaker engine braking, even though the engine is bigger.