After thinking for a minute you could also use a HPR pipe but change the gearing to be very tall, like a 15 or 16 front with like a 34-35 on the back.

The HPR pipe does not spin the motor as fast but it does generate a lot more torque.  Also I have heard of a couple guys doing this on the salt flats and hitting over 100 on their HPR zillas.

Here is a gearing calculator to tell you how fast you'll go at what RPM
http://www.everything2stroke.com/content/42-Gearing-Calculator-Quadzilla



Here is a gearing chart:
http://www.jtsprockets.com/fileadmin/files/jtgearratio.pdf