Ultramax vs. Drake flushing difference

I have an Ultramax one-piece in my bathroom. I've had this toilet for years. I just installed a Drake into a new bathroom I added on. As my new Drake has the GMax flushing system, I expected it to flush about the same way as my UltraMax. That is, I expected the same distinctive 3-second (a bit loud) flush as my UltraMax. However, the Drake is flushing lazily relative to the UltraMax. The water definitely goes out once the siphon starts but it isn't quite the rapid bowl evacuation seen in my UltraMax.

My question is, should these toilets flush essentially the same way? If they should, then I am thinking maybe there is some construction material just past the flange or perhaps a sewer line venting issue.

It should sound like this and it would be the same as the Ultramax.

http://www.youtube.com/watch?v=Y7LqkyRT5TM

http://www.youtube.com/watch?v=5faDbidCBnI&feature=related

You have to love Youtube where else would peolple be posting toilets flushing.
Wait right here!