Horrible acceleration- timing, shift points, torque converter??

[Black70c10]

Hey guys,

I'm new to the forum. I recently took my 70 c10 to Dukes Speedmaster to to get the torque converter lock-up switch installed. They did great work and I was very pleased with them. But they couldn't really help me with my acceleration issue.

I am looking for a shop somewhere in Houston that can tune carbuerated engines and that may also have a dyno. I've got a very clean 350 with headers and a mild cam, but it runs unbeleivably slow. It has a rebuilt 700R4 trans with a 1800 RPM stall. However, it just doesn't have any get up and go because it's not running throughout the power band. For instance, say I'm cruising at 20 MPH and mash the throttle to the floor... it only drops down into 2nd gear and then it shifts to third waaaay sooner than it should.

I was told that my kickdown cable is set up correct, fully taught with WOT, so I'm wondering if this may be a timing issue of some kind? Or maybe the shift points need to be adjusted? The timing appears to be set ok, it idles great and it drives very well until it comes time to get on it. I've driven crummy old beat up 350's that had twice the acceleration that this thing has. With an electronic ignition, cam, headers, et.. this thing should be halfway quick..

Any recommendations would be greatly appreciated!