I run duel 600 holley vac seconds on a weind tunnel on the street, and it works great. Just cant get by a gas station. The tunnel lags a little on the bottom, but not enough to care about, I tried a rpm performer, with a worked over 780, and it did have a snapier bottom end, and ran well, but didn't hold you in seat like the tunnel does. and at the local car cruises, the tunnel gets more respect. I say run the duels, just for the cool factor. if you like it, you'll make it work. keep smiling T.