It is true. I use Maxlead tetraethyl lead additive to each tank on mine. I have used a lead substitute in the past but switched to the real stuff 2-3 years ago. It helps raise the octane on the 93 octane gas for less pinging on mine too.

I also add ZDDPPlus to each oil change to replace the ZDDP that the EPA has mandated out of oil. ZDDP protects the high pressure wear surface of the cam and lifters.