knock is the worst con you can have... that should be reason enough

 

You wont get any knock fom running regular (87 or 89) fuel in the Magnum engine, it just runs smoother and is more responsive when you run the higher octane fuel because of the fuel maps on the PCM.

As for the casting, its on the passenger side up front by the intake manifold...but I dont remember if the timing belt cover covers it up or not though ...