What is the temp of gas coming out the exhaust pipe?

Well, we had a firefighter on TTR not too long ago saying they are reverting to Gasoline fired engines to eliminate Regen BS and discard all that emissions crap in very important life saving situations.

I have not driven a big block pushrod gasoline engine in a tractor semi for quite some time but all of that will come back to me fast enough. Particularly the shift sequence. Which would be somewhere between 2600 and 4700 or so give or take. Cruise somewhere at 4 grand.