Hi everybody, I am the owner of a 95' gl auto. Lately the car has been feeling extremely sluggish, the acceleration is horrible and the idle seems to be off. Anyway seeing the car has 140k on it I am seeking everyones opinion on which maintenance I should do. First off is there a way to clean out the intake and exhaust manifolds and would looking at the cams for scorring or pitting be productive

? I've already replaced the o2 sensor, fuel filter, oil filter, all mounts, thermostat, pcv valve, new plugs and wires, and speed sensor. My mods include removing the intake and exhaust resonator, cta intake, and magnaflow exhaust. Here is what i'm planning...new catalytic converter, timing belt(still original

), cleaning whole fuel rail, cleaning throttle body and maf. Anything I am missing for an extreme maintenace project? Thanks