So I've been tuning-in my DW1300's (new models) and they are the first set of injectors I have tuned. (besides the old models which I had replaced due to misfires)

I managed a mapping where my LTFT's levelled-out within +-2% for both Cruise and Idle with a Scaling of 1083 'cc' and a 14.08v latency of 1.584ms on 93 octane. (using "Old" Latency map in EcuFlash with GoldenEvo's XML's)

Because I am learning, I am expirimenting. I've noticed I can keep my LTFT's in acceptable ranges as I continue to lower latency and scaling.

My questions are:

Should I keep going?

If possible, do you want to get the latency as low as possible? Or is it a better goal to keep scaling as close to actual injector size as possible?

Basically, what is my goal after LTFT's tell me I'm acceptable and what are other things I should be looking for to tell me if I'm at optimal latency and scaling?

Thanks for your input,

don..

 

The goal is to get the values as close to reality as possible to provide a consistent, predictable output for both you and the ECU. If they latencies are correct there is no need to try to push them lower.

You are not adjusting how the injector works or making it better, you are providing a base for the ECU to interpret something in the physical world and apply that to a set of calculations.

 

Makes sense I guess..

I roughly started with the manufacturer stated size and latency settings and worked from there. They were of course, not even close to working values. ( I knew this was going to be the case from the get-go, but I tried it anyway.. again, experimenting)

This is where getting the mapping "values as close to reality as possible" gets a little unintuitive for me.

If I have to start with garbage, what do I consider "reality"?

 

Is my only measure of this LTFT?

 

That's because you should have used the "new" latency table and not the "old" one.

Tephra found the real scaler for the latency table a while back. I have since retired the "old" latency table off my site.

Compare what the "new" table's values are to your data sheet.

 

where are these latency tables kind sir?

 

if you kept lowering the latency you should notice one trim going positive and one trim going negative...

when doing the trim measurement, dont let the car idle for more than 5 mins.. otherwise the fans kick on and the voltage/trim goes out the window..

short drive to warm the car up
then idle for 1-2 mins... to let the trim stabilise
then get your average STFT over the last few seconds and add that to your idle trim and thats it really..

 

I actually have been comparing both tables. The values that have been working the best so far are nowhere near the manufacturer stated values in either table.

 

The car is going to AMS next Friday, so I'm going to let them sort it when they do my e85 tune. I'm interested to know how their findings will compare to mine.