If you want maximum frames per second from the Elan 7, you need to:
1. Set it to one shot mode.
If the camera starts focus tracking when you use AI focus, or AI servo mode, the fps rate decreases. Problem here is if your subject is moving fast, you have greater chance of out off focus shots (& more of them) as obviously focus will not track.
2. Turn eye control off (if it is the 'E' version).
When the camera is working out which focus point you are looking at the fps decreases.
3. Make sure your shutter speed is not too slow.
Below a certain speed (I think 1/125 or 1/250 sec) the camera can not maintain the maximum fps rate.
4. Manually selecting the center AF point might help too.
5. I also don't believe the maximum fps of the Elan 7 is as high as Canon say.
I use an Eos 30 (7e) as a second body.