Downhill Misfiring Problem

[Dabbler]

I relocated to Denver, CO from Detroit in my '73 C-10 (350/350 and a Holley 600 cfm) and now that I've arrived I'm noticing that when I'm driving downhill the engine seems to sputter/misfire unless I keep the throttle open just a little. Is this a carburetor issue or something else? All other driving conditions are good, but this one has me a little concerned, as this truck is my daily driver.

[454Man]

Carb is running lean due to increased engine speed with no throttle opening. I read up on this a year or so ago.

What's under the hood??? If you have to ask maybe we shouldn't race...