351w is slow and weak...please help

[BilLster]

it could be the heads and timing but how bad is it ?

have you run it at the track.any numbers.

sounds stupid but hopefully its something simple like your throttle linkage isnt opening the carb all the way. what type of fuel pump are you running ? mechanical right. the stock electric pumps to much fuel and can damage a carb.

timing set at ?

compression in all 8 cyl ?

so check compression then timing then throttle linkage then check exhaust for obstructions then all 3 basics fuel , air , ignition.

if you have those three you should have hp.

good luck.