Exhaust Temp numbers how hot is safe ?

[Dean Los Angeles]

Flame temperature at peak in the cylinder is over 4,000 F.
We use aluminum pistons to transfer that heat out of the system.
The cooling water around the cylinder and head is also there to prevent meltdown.
By the time the exhaust gasses reach the EGT it has cooled off considerably.

It is only one of the tools in your tuning box and is an indicator of what is going on inside the engine. As Harold pointed out, stochiometric is that point where every fuel and air molecule are paired up and maximum temperature is reached. Impossible inside an engine, but your particular engine will still have a maximum temperature at that engines best air/fuel mix point.
If you increase fuel you will have a richer mixture and the temperature will go down. If you decrease fuel you will have a leaner mixture and the temperature will go down. It is very important to know in advance where on the curve you are operating.
If you are burning fuel in the exhaust the temperature will go up and has nothing to do with engine operation.
So what does the EGT tell you? Dyno runs and time with the system will allow you to log the EGT over time and then you can use it to spot problems.

[Hot Rod Lincoln]

Good reading guys....

this is a subject we are working on with the turbo Esslinger

[saltracer1]

looked at some more of my data logger files and found that when the car ran extremely rich (float stuck) as in 9.0 afr the egt were around 1100. 1571 when afr was 12.5 or so. Blown flathead on gas. Also it got up to these temps pretty quick and stayed there through most of the gears.

[ronnieroadster]

looked at some more of my data logger files and found that when the car ran extremely rich (float stuck) as in 9.0 afr the egt were around 1100. 1571 when afr was 12.5 or so. Blown flathead on gas. Also it got up to these temps pretty quick and stayed there through most of the gears.

When I ran the AFR gauge the reading was in the 12.5 range at the end of the run which was over 180 MPH. The top of the pistons were still OK but there was some issues with a couple of exhaust valves. Since were both running similar combinations flathead blown on gas looks like the reading around 1500 which seems high might not be a bad reading for the flathead combination.