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Thread: Timing Maps for Tuning

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Posts: 61-70 of 156
2011-02-12 00:38:35
#61
Hi Ben with the OEM Nissan ecu what you see in the map is prettymuch what you get. This is illustrated if you do a log. The only variances I can think about are when the tps is out of whack, then and there the timing in the map may vary significantly when a log is done.

The other instance is, as we know the factory ecu uses an average of four cels at a time except when using the last column on the right.

But by and large what you see is what you get. I hope that helps.....a bit.

Oh and it should vary based on whether knock is detected I think.

Originally Posted by BenFenner
I don't know how the OEM Nissan ECUs and daughter board Nissan ECUs work, but I wouldn't put it past them to fiddle with timing like you've described happens on the Honda ECUs. That would be a question for Dave me thinks. If that's true, then comparing these maps would be very problematic, as you've said.

(AEM can "fiddle" with the timing too, but only if you tell it to. And you have complete control over it. For example, you can pull timing based on intake air temps which is a common thing to do. But it's not going to do anything "behind your back" like the OEM ECUs might do.)
2011-02-12 05:11:01
#62
I was thinking a bit and it seems to me that the AEM has more precise control of timing over the factory eccs. To actually be able to add or retard by frations of a degree is still something that I still can't wrap my mind around however I have seen this kind of control on honda ecus.

Not withstanding that I am still unable to understand how is it that at at maximun filling of the cylinders 20 degrees of timing can be run. This to me is only conceivable on fuels such as q16 or on japanese gas (those guys over there have some great fuel).

I have seen roms by mines, feels grid central20 and these guys run as much as 23 degrees but that I understand as they have the octane to accommodate such high timing.
2011-02-14 16:08:00
#63
What I did was take the Enthalpy guide for the boost section, then backed off 2* just in case, so my timing at 12psi is 21* then creeps up to 23* up top (rather than remaining the same as he did to redline).

For the vacuum area, I used his guide, then backed the values down and smoothed them out based off of another map. (Just now testing out this part as of 3 days ago)

With a higher flowing T28 with a T04B comp housing, port and polish, and ITB's do you guys think that I should back my timing down under boost more for the extra flow?

For the past week or two I've been focusing on what the ideal timing would be to run in cruise to get the best fuel efficiency. In my car the best mileage I was getting was about 18mpg (even trying to stay out of boost). Is it possible that the timing from Enthalpy is too advanced in vacuum and is hurting fuel efficiency? I've been told by others that they have achieved the best fuel economy on as little timing as possible in vacuum - but I had been taught that more timing in cruise would yield better power and fuel economy. Where is the line drawn from your experiences? Thoughts?
2011-02-14 16:46:15
#64
With a higher flowing setup I would definitely be more conservative with timing.

As for timing and off boost. One way I heard it is, since 8.5:1 has a lot more "space" you have to fill the space with something, so they said timing. I feel like having an EGR might help our fuel economy too, since EGR fills that space with already burnt gasses (not air).
2011-02-16 14:38:33
#65
Here is a tuned enthalpy tune. I do not like it tp values are not set up right. the car this was tuned for would never hit 112 tp.
2011-02-16 15:23:12
#66
Got any PSI numbers for those TP's 106 or 112 particularly?

0 PSI timing at 7,000 RPM is 32* by Ethalpy Base tune. We are looking at 08* and 06* in your tune right? If we subtract 1* per PSI we are looking at what 24 PSI? That's assuming you have 8.5CR.
2011-02-17 03:36:44
#67
Originally Posted by Vadim
Got any PSI numbers for those TP's 106 or 112 particularly?

0 PSI timing at 7,000 RPM is 32* by Ethalpy Base tune. We are looking at 08* and 06* in your tune right? If we subtract 1* per PSI we are looking at what 24 PSI? That's assuming you have 8.5CR.


The car did not run too well with that tune. It just dumped too much fuel. car idled nice though. Most cars Ive done I see tp scale in the high 80s low 90s. Tp scales that high should see like 30 psi of boost. even still you should always try too keep the tp scale to what your car does. If your car make 80 tp then scale the last 2 columns less. I would rather see the ecu keep a very steady timing number then bouncing between 2 boxes. If you noticed in his map he scaled the timing numbers from right to left as load increases timing goes down. this is good thing.
2011-02-17 06:08:27
#68
Thing is, unless your using TunerCode, TP from Car 1 will not equal to TP form car B ever. They might be close if you have same mods, but every engine flows differently.

TP that high is not good either, he is probably using a z32 maf and at least 370cc injectors.
2011-02-17 06:14:29
#69
I hit like 112 TP value the other night, tonight I was only seeing 106. Same onramp, same gear, same WOT.
2011-02-17 06:34:00
#70
Originally Posted by Will
I hit like 112 TP value the other night, tonight I was only seeing 106. Same onramp, same gear, same WOT.


What was the outside temperatures the other day and tonight. Probably hotter tonight right?
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