Red hot manifolds usually means lean fuel mixture and/or retarded ignition timing. I assume this engine is EFI? You may have misfire(s). You say it idles fine but is sluggish when accelerating. I would double check your timing, plug wires ran correctly according to firing order, each spark plug is firing, each injector is good, and fuel pressure is good.
If your fuel mix is lean, you could have non firing injector(s), bad O2 sensor, or maybe a bad fuel pressure regulator.
Check this - let it idle with the hood up and watch the engine. Is it shaking at all? If you manually give it slight throttle, does it stumble and shake? If so, you have a misfire and are not running on all 8 cylinders most likely.
Assuming your plug wires are routed correctly, your distributor was stabbed correctly, and you have fire to all the plugs, check timing. Pull the spout connector and set to 10° BTDC.
If your fuel mix is lean, you could have non firing injector(s), bad O2 sensor, or maybe a bad fuel pressure regulator.
Check this - let it idle with the hood up and watch the engine. Is it shaking at all? If you manually give it slight throttle, does it stumble and shake? If so, you have a misfire and are not running on all 8 cylinders most likely.
Assuming your plug wires are routed correctly, your distributor was stabbed correctly, and you have fire to all the plugs, check timing. Pull the spout connector and set to 10° BTDC.
