Go back to a post by Bill Crowell on Feb. 3, 2021- Square-bore vs. spread-bore. I posted several pictures on the difference between a Q-Jet and a TQ carb adapter-they are different. Edelbrock has both, but they use the same picture for the Q-Jet and the TQ adapter. Back in the day-the late 70's, I was running an adapter on an Edelbrock TM5 with a 850 TQ on my 68 340 Dart. I sure didn't seem to be lacking in flow, it ran very hard!