EGT's

[oldblue05]

I know it's been stated time and time again on here but I don't have much time this morning or internet that is fast where I am at now to search for this so thanks in advance for the info!

What is the threshold for safe EGT's? I was pulling a hill pretty hard last thurs when I was moving all my stuff pulling a trailer and looked down to my pyro to see the needle almost to 1200, I immedietly let off the throttle and had no trouble and have since put another 1000 miles unloaded on the engine, anyone care to tell me how close I was to converting my 7.3 pistons into liquid form?

 

[langevette]

It depends on where your probe is. Before the turbo that shoundnt hurt it muc. After the charger, that could be closer to 1500* preturbo. I before my new ip and injectors, mine would hit 1200* preturbo easily, and when towing, it got to 1500* So far mine is still running great.
BTW after the new moose and injectors, we run 600* unloaded crusing and have hit 900* pulling a gooseneck, and that was being stupid with it.
Matthew

 

[oldblue05]

Probe is at rear of drivers manifold, so your telling me with it mounted there I was still being safe? and that 1500 would be more of a max?

 

[nyteshades]

I thought the melt temp was 1220 degrees, but I would think it would have to be sustained for a bit.

 

[snaponprofile]

1250 is the temperature that the piston actually melt. I would not go over that.

 

[icanfixall]

I personally wont pass 1100 degrees. An aluminum piston is alloyed so it wont melt at 1220 but.Its getting soft and will end up a mess in the cylinders from deforming a bit. Once its deformed it will scuff the bores. If the ring grooves crush and pinch the rigs you have a piston thats ripping apart the cylinder every time it goes up and down.Remember the oil being sprayed under the domes to cool down the metal.That really helps. A few members here have lost engines due to plugged oil squiter nozzles.So you know they work very well at keeping the pistons cool.How does a top fuel drag engine keepthose pistons from melting with thefuels they use.... They usually only run them for a four second race. then they get replaced.....

 

[oldblue05]

Thanks, 1100 seems like a safe number in all reality I never actually hit 1200 but it was close and my heart did skip a beat...