Side stepping the clutch

Mopower71 said

Well I know one thing, The 509 cam I had in my 383, was a pig out of the hole. With a set of 4.56s in the rear, took right off, But couldnt keep the tires from spinning.With the 3.23s in the rear it was bad. Around 2500 rpm it started to pull like a bear.

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You may have a good point here. The 509 cam has a pretty long duration which moves the powerband up the RPM range. My 383 is balanced and has 11.5 to 1 compression. I have the MOPAR .528 lift/286 duration mechanical cam and it comes out of the hole like a crotch rocket when launched at 3500. Also, using solid lifters gives you the advantage of playing with valve lash a little to move the powerband up or down in the RPM range. You can't make a huge difference but you will notice it on timeslips.

Another consideration might be a smaller carb. The engine is going to pull a specific amount of air. One of the parameters that affects how quickly a carb goes full rich is the velocity of the air moving through it. The air will move though a larger carb at a lower velocity and if the carb is big enough it can delay the full-rich condition long enough to kill low end power and torque. If it is way too big the carb may never reach full-rich. A 750 isn't overkill on a 340 but a 650 may run much better, especially with a shorter duration cam.