I love the ratchet shifters for street/strip cars, but I do have to admit the PPP shifters are one of the nicest air/electric shifters for race applications



You will likely find the site divided between the Biondo delay boxes and the K&R boxes. I personally own two K&R's and would recommend them to anyone.



Dedenbear has the best throttle stops in my opinion, and are mostly what I see in the finals when filling out contingency forms.



Both the Biondo and the K&R boxes have timers to control the throttle stop, so no additional controller is required. Most MSD boxes are equipped with RPM switches to control the shifter, or the delay boxes can shift on a "time" basis rather than RPM. If you have a 6al you will need an MSD 8950 RPM switch for the shifter.



(FYI - NHRA forbids having a wire connected to the "TACH" connection on any delay box (Mega400 and Mega450 boxes in particular) which prevents the box from being able to be used to operate the shifter on RPM. Hence, the need for the RPM switch).