ECUTune, for those of you that have/had it

[Trevor]

Originally Posted by Trevor

If confirmed information is available, i.e. "Those of us who genuinely have the ability to monitor ignition retard and advance have not seen this." presenting the figures would surely close any argument.

Having had OT's select monitor in both of my SVXi many months back, I was able to view both of my car's timing. While my stage 3 was pulling 10* of timing whenever i got on the throttle My bone stock SVX was pulling timing in high load situations. Most I ever saw was 8* of retard.



There aren't any figures to present except to say that when you drive around monitoring "rtrd" and "adv" you clearly see that on a healthy SVX the factory ECU doesn't retard the ignition advance. It does the opposite. It adds ignition advance. "rtrd" is just the label for a memory location in the ecu which holds the immediate value from the translation of the knock sensor signal. A value of 8 does not mean 8 degrees of retard. It means 8 degrees of advance. A value of -8 means 8 degrees of retard. The factory primary ignition map is extremely conservative under high load to say the least; the ecu uses the knock sensors to seek out knock and add in additional advance up to the threshold of theoretical maximum advantage.



It's good to get actual figures rather than conjecture.

Tom, would you not consider it normal for the timing map to retard the timing in high load situations, given that it is a high compression engine pulling a heavy car at low revs?

With the auto box being programmed to prefer high gears and run the car between 1500 and 2000 rpm all the time, this I remember as being the range where my old 2.2 litre Matra used to pink badly under load in top.

As I see it the SVX is constrained by the TCU to constantly pull within a range that leaves it open to detonation, even naturally aspirated.



Valid figures are void of semantics. Currently confusion is the order of the day.

The existence of a figure representing retard or advance requires a baseline figure. It is now suggested that the base line is zero in respect of the figures presented. Does this align with the piston at top dead centre. If not what is the basis of zero?

Please, can the term “Pulling” be avoided in the interests clarity and accuracy.