Thread: Performance Tuning Plan

howdy!
um i am also in the process of performance mods at the moment so hopefully this thread will grow
um firstly i will say and im sure almost everyone is going to say if you want to tune accurately you MUST have the egt probe "pre" turbo otherwise its just a guessing game! i once thought post turbo was the way to go but ignore the installation instructions and 4wd magazines etc etc pre turbo is the best.
um i cannot see any reasons why you shouldnt play around a bit in the quest for more power remember more denser and pressurized air plus fuel equals more power

We have the EGT probe pre-turbo, Turboglide in Wollongong recommends the probe be placed 2 inches post turbo, we do dash and trum repairs on brand new trucks, they have the probe post turbo ..... no wonder ther is so much confusion.

A 2nd EGT meter and probe has just arrived in the mail, I puttin this probe 2 inches post turbo and keeping an eye on both guages to see what the differences are.

Glenn

Originally Posted by The Mutt

A 2nd EGT meter and probe has just arrived in the mail, I puttin this probe 2 inches post turbo and keeping an eye on both guages to see what the differences are.

Glenn

I look forward to the result. Mine's also post turbo as advised by a respected isuzu repairer.

Why would you measure the EGT post turbo where it is not important and take a guess at what the temp is pre turbo where it is important?

On a truck that is well and truly sorted by the manufacturer and is expected to many km's daily, they can have the probe post turbo because the relationship to pre turbo EGT has been established and reduce the risk of a failed probe damaging the turbo.

In our landies there is little risk of probe failure, particularly if it is the usual 6mm dia and not exposed junction type.

Your turbo could have up to 300C temp difference across it in some conditions. Better keep that temp to 450C to be safe.

Or put it where it belongs and crank to 750C worst case.

At 3000rpm full load I'm at 21psi & 750C. Just checked that tonight. Still no intercooler.

Originally Posted by Bush65

Why would you measure the EGT post turbo where it is not important and take a guess at what the temp is pre turbo where it is important?

On a truck that is well and truly sorted by the manufacturer and is expected to many km's daily, they can have the probe post turbo because the relationship to pre turbo EGT has been established and reduce the risk of a failed probe damaging the turbo.

In our landies there is little risk of probe failure, particularly if it is the usual 6mm dia and not exposed junction type.

Exactly.

I suspect that modern diesels may have post turbo EGTs as the egt at the DPF (and or oxy-cat) is important for regeneration.

As an aside - A friend of mine works for a company that designs and builds DPFs for OEM applications. The max temp specs the engine manufacturers give him (that the DPF has to handle - so basically post turbo EGT) are very high. I suspect that modern diesels may have some high performance alloys that allow them to run higher EGTs???

Originally Posted by isuzurover

Exactly.

I suspect that modern diesels may have post turbo EGTs as the egt at the DPF (and or oxy-cat) is important for regeneration.

As an aside - A friend of mine works for a company that designs and builds DPFs for OEM applications. The max temp specs the engine manufacturers give him (that the DPF has to handle - so basically post turbo EGT) are very high. I suspect that modern diesels may have some high performance alloys that allow them to run higher EGTs???

Frighteningly so, I measured a ZD30 in a auto patrol at 830 degrees preturbo, UNCHIPPED and unladen going up a reasonably steep hill. Its no wonder the engine we just replaced had melted pistons etc, it had towed a 19 foot van for 4 hours into a headwind at 90KM/h!!!! It then developed a miss and a chronic front crank seal leak

Game over.


JC

I was reading a document on DPF's the other day, one of them trips a fault if the EGT is over 1000C during regen.
But I suspect regen is done with retarded injection timing which is basically throwing a flame down the exhaust port, the average cylinder temps might not be that high.

Having said that, my Isuzu has seen 900C more times than it should and it keeps trucking.