Like the title says, my 71 440 runs like a slug and has very little low end torque. It doesn't even want to spin the tires with 3:55 gears. We have a few theories on why it may be lazy but wanted to check here for some additional ideas. Here is the background on the engine. This was a bone stock 71 440 that has been in my 74 Roadrunner for years. It ran great when the engine was put in the car but over the years, the stock AVS would dead spot and no amount of tuning or rebuilding would fix it. Since there were some other small issues to address on the engine, we decided to remove it and replace the cam, timing, chain, carb and intake. Used a Crower 267HDP (220 and 223 @50 with 478 and 486 lift 112 lobe separation angle). On went a Holley Street Dominator and a new Edelbrock 800 Thunder Series AVS. It should be noted that we are using stock 73 HP Magnum exhaust manifolds. The car starts, idles,and runs nice and doesn't even really have any lope at all from the cam. The timing is set at 11 initial and doesn't ping. It bogs a lot when you step on it from a stop. Air door has already been adjusted some but hasn't cured the problem. So, anybody got any ideas? Is the Street Dominator killing off the bottom end in this combination despite the fact that it is generally known as a good low-end intake? I think the AVS carb should run pretty good on a stock-type engine and not be too much. The cam is also pretty mild and should not make a dog out of it. We have a Weiand Action Plus we can try to see if that brings back some of the low end but it is so dead I don't know what will help. A 440 like this should melt the tires. Any help would be greatly appreciated.