Duramaximizer causes knocking sound?

[rvann]

Installed the Duramaximizer. With the power knob turned all the way up and from a standing start using full throttle a rattle comes from the enginge untill boost forms. It sounds like a gas engine under heavt pinging or pre ignition. What is up??? This is with the truck empty. Worse under a towing load.

[tcelano1]

rvann,

I had the Duramaximizer, and I noted the same "knocking" sound. I could turn it up to maybe 2/3 before it would come in. Being someone who takes pity on machinery, I didn't like that sound at all, but I'm sure that there are plenty of folks who have oil analyses to show that it doesn't hurt anything. It reminded me of those old mechanically injected diesel bus engines when you first pull them off idle. I ended up taking the maximizer off, as I think the Hypertech programming produces more power, and is more drivable. The Hypertech doesn't make the aformentioned sounds.