rcmiller32 wrote:
Having worked on both the 427 and 454 GM V-8 engines in fire equipment over the years. Both will get glowing red hot exhaust manifolds when they are being worked hard. Have scene some get the exhaust red hot all the way down to the muffler.
The one poster about the harmonic balancer is correct. They fail making it very hard to set the correct timing.
X2 - I was a GM mechanic for 20+ years. I suggest replacing the balancer to make sure the timing is correct. Some manifold glowing is normal in the 454 under heavy load. The old 400 small block had the same issues.