Pyrometer Maximum Temperature

[JackConrad]

       We have installed a pyrometer on our MC-8 (8V71/HT740).  We run about 450-650 when cruising at 65 on roads with gentle hills.  We have not been on any significant hills or mountains yet.  My question is "What should I consider to be the maximum exhaust gas temperature?"  Thanks in advance, Jack

[H3Jim]

My ford powerstroke has a max temp of about 1100, but it also depends on where the temp sensor is, before or after the turbo.  After the turbo, the max temp is lower since the turbo will knock it down some and you are wanting to ensure that you keep the temp below the melting point of anything in the exhaust path. 

Normal crusing on the freeway my ford  runs about 600, but any kind of load pulling up a hill, it goes up dramtically.  too lean makes it go up too.

[JackConrad]

8V71 NON Turbo.  Sensor is installed slightly downstream from fitting that combines left and right exhaust manifolds.  Jack

[Frank @ TX]

Jack,
The melting point of your aluminum alloy pistons is about 1200 degrees F.
The exhaust gas will be hotter the closer you get to the piston face.
I wouldn't want to operate these engines any higher that 1050 exhaust temp.
Hope this helps.
Frank

[larryh]

As a mechanic for almost 40 years I always told my customers 900 degrees max and to watch the exhaust pipe at night and if you see a red glow back off and watch pyro .

Larry Higuera

[Paso One]

my 2001 Power stroke no engine mods has hit 1100 on up hill climb pulling car hauler. most times crusing at 65 runs 700  Ford forum guys say melt down on power strokes at 1300  I bet the dd wouldn't like 1100

[TomC]

I saw a simple sign on a yacht once that I've never forgot "over 1200 degrees costs money" that was above the pyrometer.  Most 2 strokers have to be seriously overfueled (big injectors) before you'll be worried about exhaust gas temps.  And most recent rebuilds on 2 strokers have iron top two piece pistons to boot.  The engines you have to worry about are mechanically injected 4 stroke engines.  Anything electronic, a pyrometer is a waste of money since the computer will take care of that worry.  Good luck, TomC