I just put a new edelbrock Proformer intake on my 77 350 + MSD ignition box, new Qjet 4b carb and electric fan and tuned it up, new plugs and all that.
I have great top end but low end not so good,(it sucks).
Give me help please.
Thanks,
John

A Edelbrock performer cam would work well with our combo from idle up. What rear gears do you have? That makes a big difference in acceleration.

I bet you don't have enough ignition advance. Use as much initial advance as your engine can take (at least 12 degrees or more). Use a dial back timing lite to check your total advance--initial + distributor (disconnect the vacumn for this test). You want between 36 and 40 degrees total at 2400 rpms. You may have to recurve your distributor advance. After doing dozens of small block Chevys 38 degees is about perfect for 95% of them. I guarantee if you follow these instructions your engine will perk right up. Oh, also make sure you have full throttle, you would be surprised how often this is overlooked after a carb/manifold swap.

Thanks, I will gave it a try and let you know what happens.

I'd check gears. If you have an Old Lady rear end then your going to have a issue with launch or what a lot of people mistke for low end power. Once your RPMs are inside their optimum curve then it feels like its starting to respond. At this point you could be close to 60 Mph.

I can talk about "Old Lady" rear ends because I have had to deal with having lots of good power and a set of gears that were made for gas miliage. What I described was the feeling. Between 60 to around 140 I had the road but who needs it there? And let me tell you when you pass 120 its scary, especially when you have like 3/4 pedal left. With 2.73:1 gears I never topped out even with a 350 Transmission.

Definatly check your ignition and I agree that lots of people running around these days don't have more than 3/4 throttle max. Its assumed that you do just because you did once. If you have a bud sit in the truck floor it, then see of you can rotate the throttle inkage by hand, at the carb, if you can you do not have W.O.T. when the pedal is in the metal.

If you are running less than 3.08:1 gears then fix that. If you are running 3.08, which was the performance rear end in the 5th gens, that is what I call bottom line gears. Or bear minimum. With a THM 350 those will give alright performance.

Performance is based around your engines power curve and its important to know what yours is. The best response you will ever get will be in the power curve so your other components have to be centered around that, getting into the RPM range and keeping it there. A 300 Hp car or truck that has been planned around its 300 ponies will be just as exciting to drive as one that has a 400.