A49 fuel curve?

[STV_Keith]

Put a bone stock '97 2.5/260 powerhead on my rid the other week and have been playing with it for it couple of outings now. Kinda getting some baseline info on what the stock motors do (since this is my first stock one).

Anyway, the EGT's seem to sit around 1050-1100 at cruise up to 6000rpm, then go up to around 1250 from 6000-7000rpm part throttle (cruising at like 80mph or so). Also, WOT EGT's are 1300*. Is this normal for a stock fuel curve? I was under the impression that 1200* was as hot as I wanted to run one.

This motor has about 100hrs on it, and the old owner ran it fairly hard and didn't even have EGT gauges, so I guess if it's lived this long, it will continue to live, but man that seems hot.

[props4u2]

There are two high and two low temp ranges with pyrometers, one high reading is from a rich mixture, too much fuel, burning fuel is running down the adapter plate over the probes reading flame temp., the other is a lean condition, too much air not enough fuel, acting like a cutting torch, not good. A low reading can be from raw unburned fuel cooling the probes or not enough fuel to burn which is way lean, usually only happens on one cylinder as the fuel system would be too lean to run the motor. Best to do a piston/plug reading to see where you are and use the pyrometer as a refference.


Lee

[us1]

There are two high and two low temp ranges with pyrometers, one high reading is from a rich mixture, too much fuel, burning fuel is running down the adapter plate over the probes reading flame temp., the other is a lean condition, too much air not enough fuel, acting like a cutting torch, not good. A low reading can be from raw unburned fuel cooling the probes or not enough fuel to burn which is way lean, usually only happens on one cylinder as the fuel system would be too lean to run the motor. Best to do a piston/plug reading to see where you are and use the pyrometer as a refference.


Lee

Exactly, that about covers it.