Exhaust manifold glowing red hot

My exhaust manifold gets like that after a sustained amount of throttle is applied.

Came to this conclusion after gassing the car with 1/4 throttle up a mountain road.

Length of uphill is approximately 3 miles.

In my opinion, these could be the convicts:

Clogged cat converter.

O2 sensor is acting up.

Timing is off.

But i just smogged the car this January. So the cat might be out of the possible suspects.

If it was an O2 sensor, the car would be running rich, combusting the excess fuel in the manifold, or somewhere else in the exhaust system. And i would be able to smell it while idling. Would also idle rough.

So would it be my timing?

Thanks in advance guys.

I'd say the cat TBH, your right about the O2 sensor and the timing would make it run rough.

magweal wrote:

I'd say the cat TBH, your right about the O2 sensor and the timing would make it run rough.

Thats what im thinking. But it just passed smog without a problem in January. Which makes me a little suspicious about it not being the cat.

Hello again! Hey, get a picture of the glowing part!