Small Block 350 engine jerks slightly... HELP!!!?

[AK]

I have a SB 350 engine in my 71 Impala.  I just installed a new Edelbrock intake and 600 cfm 4 bbl carb a couple months ago.  The car starts fine, but I noticed when I put it in Reverse and back it out of the garage, I feel a slight jerking. Also, when I'm cruising and I slightly press the gas, I feel the same jerking feeling (very slight, but its noticeable).  When I hit the gas hard, it accelerates fine with no jerks or hesitation.  I thought maybe my carb needed to be tuned.  What else could this be?

[schurz04]

Check your motor mounts, transmission mounts, and suspension bushings.  It could be a lot of things, start there.  If not, its something inside the engine.

[garyra8668]

check your fuel pressure. i hope you changed the fuel filter when you installed the new carb. also could be the universals on the driveshaft. this list is not a complete list of things that could cause your problem, but it is a place to start.