Small Block & Big Block Chevy Specific - Why is it doing this?

My enginne kind of sputters when Im just coasting in any gear.(5spd) I tried leaning it out a bitthinking maybe it was getting too much fuel but its still doing it.
The other thing is that when I floor it and it gets past about 3.5k it chokes for a sec then goes and then it chokes again and picks up again and so on till about 5.5k. Is it running out of fuel? It didnt used to do this before.
any help would be greatly appreciated, its really makin me:mad:

Just wondering what air cleaner are you using? What type of injection do you have on that thing? What are you using to get the fuel pressure regulated down or did you get a low pressure pump? If you think its to rich check your fuel pressure, it shouldnt be more than about 6 or so (assuming your carb'd)

Our cars are like sisters.

Yeppers, it is carbed with a 6.5" air cleaner(I know its small but it was working fine with this air cleaner) The fuel system is running off of the factory fuel pump with a fuel press regulator. When I pull a plug, what should it look like if its running lean?

Pull a plug and if you notice any ash or overly white areas then you are running too lean and may need to check your fuel pressure and your filters. If it is rich(black) then you may need to clean your carb or check your ignition system thoroughly. What type of ignition and carburetor do you run?

Dude take that air cleaner and toss it, I had that, it would do the same thing and it dosent even look dirty, it was doing EXACTLY the same thing. Take it off and drive it it will fix it. I ended up getting one of those carb hats from ebay with the dual inlets then I run ducting down behind each headlight. It had me fooled for 3 fucking days.

I was looking into those carb hats. I found the one with the single inlet on summit but it was $60 so I was holding off on it. I will drive it tonite without the filter and see what it does. Do you have any pics of your set up? Sounds pretty nice.

Smokey, Im running an edelbrock 650 cfm carb with an MSD Street Fire HEI dist. I did notice the cap on the dist. kinda wiggles a bit and I checked the screws to make sure they were on right and they look to be on right.

I was looking into those carb hats. I found the one with the single inlet on summit but it was $60 so I was holding off on it. I will drive it tonite without the filter and see what it does. Do you have any pics of your set up? Sounds pretty nice.

Smokey, Im running an edelbrock 650 cfm carb with an MSD Street Fire HEI dist. I did notice the cap on the dist. kinda wiggles a bit and I checked the screws to make sure they were on right and they look to be on right.

If all else fails try cleaning you distributor out to make sure there is no moisture in it and also check for cracks, you will see them in the cap cus it will be burned around them. And dont toss out the possibility that your distributor could be bad, I have had horrible luck with the msd units.