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Post Info TOPIC: New map definition, Made some major new finds.


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New map definition, Made some major new finds.


I refined the map definition file for the Enginuity.org map viewer editor (See Map File Downloads for details )

I have identified which maps are fuel, ignition, etc and what the axis values are, RPM, throttle, Inlet Airpressure, etc. In the process I made some major discoveries...




First thing should jump out at you, besides that there is an individual map for each cylinder, is that there are two complete sets of maps, A & B. (A is the default).

So how does the ECU decide which map to use? It checks the COV3 input of the MAD port connector at power up to select which map to use. I had discovered this and posted it earlier in regards to some gear maps. It never occured to me that it would select different maps system wide.

This means that when we start reprograming the ECU you will be able to choose between two totally different maps at the flip of a switch. Before you NOS guys get all excited you have to turn the bike off and back on to switch maps. No realtime flick of the switch NOS map change, sorry

What about the stock bike? This is the jumper mentioned in the service manual that some model ECUs are supposed to have and others arn't. Of course the question you are all dying to have answered...is there some secret derestriction to be had by using the jumper? Well one of the cool features of Enginuity Map software is that it allows you to compare two maps against each other and display the differences.

The Ignition maps A vs B? No difference.
The Fuel maps, both throtlle/rpm and airpressure/rpm, A vs B? No difference.

A perfectly good dual map setup that is totally unused by the stock bike setup.

Another interesting thing. A special Ignition map for first gear only that overides both the A or B ignition map. This is the map shown above. See that big red zone between 3900 and 5500 rpm? That is not in the other maps. Now I'm assuming that these values are advance. Check me if I'm wrong but you advance the timing as you increase rpm. The data in the table increases with RPM so it must be advance.

Why would you over advance the timing in that limited rpm range for just the first third of throttle?

By the way did you notice that the first half of the map deals with just the first 10% of throttle travel? The bike idles at around 20% throttle voltage and half the map deals with 21% - 31% throttle. Explains the the non circular shape of the TPS pulley.

And the thing that amazed me, I don't why it would, but the Fuel and Air maps are different between cylinders. I can understand there would be diffrences but how would you tune such a map? Have a header pipe with 4 oxygen sensors, one in each pipe?

It explains why the MAD box makes you go through doing each cylinder.

BTW a note about the x and y axis boxes at the top and left of the maps. These values actually come from lookup tables in the map itself. Take the throttle for instance if you wanted less resolution in the lower throttle range and more up hi you could change these values in the table and they would be changed when you rewrote the map. Of course you would have to do a major change of the table itself. Not sure it would be worth it.

Also for all these maps the RPM is a guesstimate. I will eventually be able to calculate the engine speed down to a millisecond but until I measure and calculate the internal bus clock of the CPU its a rough guess. Same goes for the injector on time and the ignition advance value.

The crank speed number is a value between 0 and 65536. If the crank value is half that I call that 50% rpm and multiply it times 12,500. Why 12,500?

You can't see it in the map above (a little on the far right of the 3d map image)but the last two rpm values work out to 90.6% and 93.7%. All the way upto and including 90.6% the values steadily increase. Then at 93.7% they drop and are flat across the upper two thirds of throttle. Between these two must be redline.

It seems to me the best value would be one that gave you 92.15% at redline or in other words 108.5% of factory redline. Problem is I couldn't find any firm agreement online about what factory redline is. 10,750? 11,250? I know 10,200 is the limit in 6th gear because of the speed limit. So I went with 10,750 and therefore picked 12,500. Call it design redline.

Anyway have funning browsing through the data. If you find anything interesting let us know.







-- Edited by RidgeRacer at 17:38, 2006-12-19

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I think the actual redline is 11,600, which I saw somewhere online...


 


Jeff



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hi RidgeRacer - great work, congratulations on your tenacity and progress thus far.

I can confirm the factory ECU rev limiter is 11,600 (within +/-50 rpm anyway).

I've built a 2400cc V8 engine using zx12 heads, barrels etc and made my own block. I'm using the standard ECU and ignition systems (1 system for each bank). Its a racing engine and I have a memory tachometer - hence the highest recording I have from hitting the rpm limiter is 11,600. The engine is running on methanol injection rather than the standard electronic injection.

I'm following your progress with great interest as I'd love to keep using the standard ECU / ignition system, but some tuning features would be great.

I'm after any tips at all if anyone out there knows any ECU or system mods to increase the factory rev limiter at all.

Good luck - Simon



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Simon


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Thanks, though I think my efforts pale in comparison to making V8s out of ZX-12 bits

Interesting project. Do you do this for a living or do you just have a real exotic hobby?

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Well, not sure if your efforts do in fact pale in comparison to mine, talents applied in different areas i think!.

This engine is pretty much an after hours effort too, although i'm an engineer (mechanical) in my day-life too. I need the work to pay for these exotic hobbies as you put it so well!

simon

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Simon


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do you suppose that red area of extra advance on low throttle and mid revs is something to do with reducing backfire or burble or increasing engine braking when coming down from high revs with no throttle (like say into a corner, or kicking it down into first when coming to a halt)? - but then why only in 1st gear?


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My opinion is that it is there for ridability. We are talking about the first 10% of throttle travel when moving between 25-40mph. I think its there to keep the engine from suddenly coming on power when your transitioning from trailing throttle to rolling on throttle in corners around town.

This bike has so much torque down low it takes a conscious effort not to spin the rear tire coming out of corners. In fact the first two times I wheelied my ZX-12 it was an accident.

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