you sure you dont mean heffier creek road? the one that comes out near ma ma creek? cant remember any canyons on murphies, murphies is the alternative to the Toowoomba rang on the crown nest side
And yeah if it is Heiffer creek all the trucks from the Lockyer use it to get up tp Warwick and have a fair bit of trouble stayin on thier side of the road :S ha ha
The gold coast hinterland has some great ones
springbrook- mudgeeraba road
nerang - murwillumbah road
oxenford - tamborine road
another good one is up over nebo down to esk, then esk - hampton road over to toowoomba then home