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Diesel AFR/Timing Tuning

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I'm particularly interested in learning how to tune for correct AFR and timing at what engine load vs RPM. I will be using a piggyback to tune.

I would be working on a 2003 land cruiser 100 series Diesel Turbo engine/ Toyota Hilux as seen in your diesel tuning module.

I will also be road tuning as I have no access to a dyno.

I have a EGT Gauge and AFR meter too.

What parameters will I log/monitor on the factory ECU? Any other tips ?

What you will be able to do with the tuning will be dependent on the capability of your piggyback ECU. I'd start by researching to see if there is any information around on what the safe maximum boost level is for the turbo fitted to your engine - The 1KD engine in our Hilux has a very weak shaft in the turbo and they fail easily if you raise the boost. In general you want to raise the boost as much as you safely can as this will add more air to the cylinder. you can then add more fuel while maintaining a safe EGT and AFR.

A good starting point would be to increase the boost by 10% and then add 10% more fuel. This will give you a worthwhile increase in power and torque without putting excessive strain on the engine. Beyond this more careful monitoring of the EGT is necessary.

What about Timing, aside from that specific car. How would I know how much timing is safe to add and at what RPM and engine load?

What parameters will I log/monitor on the factory ECU?

Tuning the injection timing is similar to ignition timing in a gasoline ECU but it's going to be all but impossible to validate your changes without the use of a dyno. You're often making changes that may result in subtle improvements in power and torque and sensing these on the road is going to be challenging.

The reality is that the injection timing, pulse width and fuel pressure all play a part here with each effecting the other so it's not possible for me to say that you should run a specific timing value. Have you gone through our Diesel Tuning Fundamentals course yet? This is explained in detail in the course along with practical demonstrations.