Carbed lsx cutting out

[clementime56]

I have a 410ci ls in a 56 ford f100. It starts to cut out at around 5k rpms only under load. In neutral it revs just fine. The motor is 6.0 block, compstar crank and rods, diamond pistons, l92 heads, gm single plane intake, holley 950hp carb. I have checked fuel pressure and that stays consistent at 6.5 psi all the time. I am controlling it with a 6ls msd box. Does anyone have any suggestions or ideas to help me out.

Thanks,
Brandon

[Chevelle598bb]

What do the plugs look like? Does are they fuel fowled like the ignition is cutting out or do they look like its running lean? What timing curve are you running?