1. Some says that EOI longer than 5-6°makes little effect for power, but increases EGT.
2. Some says that you must not advance SOI more than 2° than original to not ruin engine.
3. Some says that when you turn EGR OFF you should also advance SOI in EGR range to compensate EGR ignition delay effect.
4. Some says that SOI must not be bigger than 30° BTDC.
5. Some says that EOI must not bigger than 15°.

I found these assumtions in many forums related with EOI, SOI and duration, but there are too few experiences, no literature supporting them, that i don't know which i should trust.
Please share your experiences, any literature related to EOI,SOI tuning.

I have attached my Alfa 166 original EOI (calculated with EOI calculator v1.1)
If assumtion No. 1 is correct would it make any good to retract EOI in range 30-70mg by advancing SOI?


P.S. I have old Alfa 166 2001 2.4 JTD (pre-face lift), modifications so far maded:
.Max IQ from original 54mg -> 70mg (duration, soi maps limit)
.Smoke map AFR ~17->14.5
.WISH MAP increased to 70mg
.Temperature limit from ~55->70mg
.SVBL from 2300 to 2550mbar

Did mistake in previous EOI calculation, fixed one

Try to time the EOI at 5-6° degrés ATDC.

The engine will be fine.

The ecu's are getting more sophisticated but the engine is still a simple piston going up, you want the fuel in just before/after the intake valves closes.
On a diesel its the compression that makes the fuel ignite so the spark timing is relevant, you can aim a bit before or after.

Fuel in, piston at the top, valves close, power, combustion, never forget that. ;)

Hi tommic

I'm searching for the exact same information, but can't find anything, and nobody has answered here with some literature or detailed answers.
Have you found any information in the meantime you want to share?

I've a VW Passat 2002 with the AVF engine, and I will make some changes to the SOI maps to correct for the non-existing EGR :)

Hope you'll write back :)