Thread: EGT sensor - upsream or downstream of turbo?

Originally Posted by Dougal

What boost and EGT range is that at?

thats the differance between the two positions
cheers phil

Originally Posted by discowhite

thats the differance between the two positions
cheers phil

Sorry, should have been clearer.
The pressure and temp difference across the turbine varies with both the current boost and the exhaust gas temp.
So what conditions of boost and EGT give your 200 deg drop?

Originally Posted by joel_nicholson

But when mounted upstream it can still be used as a driving aid in precisely the same way

The principal and virtually only use of a pyrometer is to determine excess fuel still burning in the exhaust tract after the heat energy contained in the hot expanding gases has been used to drive the turbocharger. you can either back off the throttle or get the fuel system adjusted. I repeat, ALL pyrometers in diesel engines used in heavy trucks are installed downstream of the turbocharger.

Originally Posted by Brian Hjelm

The principal and virtually only use of a pyrometer is to determine excess fuel still burning in the exhaust tract after the heat energy contained in the hot expanding gases has been used to drive the turbocharger.

How exactly does a pyro detect excess fuel still burning in the exhaust?
They can only measure the temperature of the gas at one point.

Originally Posted by Dougal

Sorry, should have been clearer.
The pressure and temp difference across the turbine varies with both the current boost and the exhaust gas temp.
So what conditions of boost and EGT give your 200 deg drop?

mt white on the F3, same hill same car same speed. after turbo i get 500deg, b4 the turbo i get just under 700deg. thats 5 gear 110kph.
not sure on boos psi? not full throttle bout half, probably 15psi.

note,
ecu upgrade, intercooler, 2.5'' zorst no mufflers.


cheers phil

Originally Posted by discowhite

mt white on the m5, same hill same car same speed. after turbo i get 500deg, b4 the turbo i get just under 700deg. thats 5 gear 110kph.
not sure on boos psi? not full throttle bout half, probably 15psi.

note,
ecu upgrade, intercooler, 2.5'' zorst no mufflers.


cheers phil

Thanks for that. I've got a second pyro to install downstream, but it's one of those jobs I haven't yet got around to.

Just a Question regarding the EGT Gauge ,I 've got my Thermogaurd thermocoupler installed Upstream , the Fuel Pump settings are back to Factory settings, originally had the Pump tweeked ( star wheel spring preload and eccentric cone position changed etc ) I found out on a few test runs that I can reach unsafe EGT temp rather quickly even on factory settings , if anyone knows the Berrowra hill Climb on F3 Foot flat to the Floor 15psi boost and still willing to Climb , with a original exhaust and straight through Muffler , I can quite easily reach 600-650 degrees on factory settings , she is definitely not smoking as much as she did before so this would be a good indication on a better fuel burn ,yes/no? but getting back to the Question ,could anyone confirm that this is rather unusual for Temp to reach that level even with Fuel Pump being very conservative ? Any Help would be much appreciated in advance..

600-650 isn't an unsafe temp. I've been running my Isuzu up to 800 on the odd occasion. 750 is the point where I back off, but with the lag in the probe it often goes past.