Stevil

When I take fuel out by using the normal PMI settings, what does this take fuel out of? If at 100% and I drop say any RPM to 95.2%, what is this 95% of? Is it the sectors corosponding to the rpm range. If I have 1.49...
in the N15-N20/P19-p20 sectors, am I taking 5% from these values???

Also, I have similar mods as Chuck W.(Cewrx7r1), so have imputed his maps. I dyno'd today(will post as soon as I can get the image smaller(2.2mb is best I can do)). I made 310.4 in 3rd gear w/ .85 set on PFC but .98 as a max reading(not sure if it stayed at that boost, no datalogit). At 4000 rpm my A/F's dropped below 10(off the chart, so not sure how low). So, I compensated by decreasing PMI 4000rpm and up. I took about 3-4%fuel out from 4000+rpm. Next run I get 312.7, still A/F dropping. So, I pulled another 2% out and between 5k-6k my A/f was readable at about 10.3. But before and after it was off the chart. I made 317.0 this last run. I stopped there. Is this a good way to tune or should I tune using the fuel grid?

When I can, I will post the dyno. I have to have still a good amount of HP avail w/ intake, 1200 secondaries, IC, HKS twinamp, full open exhaust, fuel pump, stock turbos, motor. Plus it was like 70F outside and a big fan blowing on engine and cool downs between runs. Still 45 hp over my HF cat dyno runs and no ignition breakup as before.


Thx
Steve

es

That's about the easiest way to get your desired A/F on the dyno. To determine the % from the map you need to know what the ms values are in the base map & calc the overall inj time by either using the recalc feature in the datalogit or by doing manual calculations for each cell! (yea right!)

Later after you get a datalogit you can make adjustments to the grid maps if you desire. Another way (somewhat better) is to lower the PIM % on the dyno is through the Voltages 3.5v and above. This wont effect the part throttle parts of the map. Only under WOT...

Luck & enjoy.
Eric.

cewrx7r1

iTrader: (2)

If you had a datalogit, it would be a little easier to understand what is happening.

1. The Base Map which can be seen only with the datalogit and a PC, shows injector operational times.

2. The 20x20 Injector/Fuel Correction Map, is used to make exactly 1 to 1 corrections to the base map grid. When a datalogit RECALC is run, only these corrections are used and written to the base map. A RECALC also resets all FCM cells to 1.00, or 100%.

3. If BM cell (17,10) contains 17.024 and FCM(17,10) contains 1.35; that means 35% more fuel is added to BM(17,10) when it is run. If a recalc was done; BM(17,10) would now become 17.024*1.35 = 22.982.

4. The PIM section has two correction sections; 1 by rpm, and 1 by boost. These affect a wide range of the base map cells at a time and work in conjuction with the FCM.

5. If you set 4000rpm to 104 or 1.04 which is 104%, you add 4% more fuel to the total fuel. Which total fuel? If 3000 and 5000rpms are at 1.00, then the extra 4% would be prorated between them. Thus 3500 and 4500 would run about 2% more fuel with only the 4000 area being 4% more fuel. This would add 4% more fuel to my previous BM(17,10) cell which already had 35% more due to FCM(17,10). Thus we now have 22.982*1.04 = 23.901 operational. Remember, a recalc will leave this value out. In truth, all P rows from 1 thru 20 will have the extra 4% more fuel added to them from between 3000 and 5000 rpm when they are used.

6. The same basic idea works when using PIM pressure. You only adjust fuel base for that pressure setting. But it affects all cells that are run when the PFC determines that the pressure area is active.

7. Thus cell BM(17,10) from above can now have its fuel changed by a third factor.

8. After a recalc, looking at a base map reveals errors just like when we have looked at calculated timing split and found negatives. I used a wide band with the datalogit and after many runs, I converted all my fuel changes to FCM values and then did a recalc. Then I fixed the minor errors and recalced again. This gives a smooth easy to understand idea of engine fuel needs.

See my attachment.

Stevil

So, I am tuning somewhat in the dark, not knowing basemap values. But, does it really matter. I have dynoed, found out I am running rich w/ my base maps. So, I could just continue to dyno tune w/ PIM(not PMI, duh) adjustment, correct?


Ya, a datalogit would be better/easier. Actually all the guys that have datalogits should not post fuel correction maps overhere(well they arent really). Since anyone who inputs it takes a risk, not knowing what the inputee and the copied basemaps are.

Chuck, thanks for the explanation and the all the time involved. On your new base map, why are there #### in some of the boxes? Does your fuel correction map now have 1.00 in everybox?

Kind of strange how everything effects the basemap. The PFC should have just a basemap that is tuneable. Seems strange to have a map on top of a map, that can then also be adjusted, by another(PIM) way. Sheesh.

Last, PIM changes basemap also. Does it change basemap before fuel correction map is taken into account? Or I guess it just adds/subtracts to fuel map. Again Sheesh.

Why have all these adjustments? seems there should be no basemap or just a basemap of 1. Then that could be adjusted.

Ok, last(really), why change basemap at all? Just keep the same basemap and adjust using fuel correction& PIM?
Sorry for double similar questions.

Thx, at least this answers my previous post(thanks again Chuck)
Steve


And to clarify, PIM under normal setting adjusts fuel by rpm, and I can adjust fuel by boost using volt screen. Is this the screen that pops up if I highlight a given rpm on the normal PIM screen, this takes me to a volt screen?

cewrx7r1

iTrader: (2)

" why are there #### in some of the boxes?"
Your Excel is not set up properly to show all 5 digits and the decimal.

" Does your fuel correction map now have 1.00 in everybox?" Yes

"Kind of strange how everything effects the basemap. The PFC should have just a basemap that is tuneable. Seems strange to have a map on top of a map, that can then also be adjusted, by another(PIM) way. Sheesh."
The 20x20 FCM allows exact but time consuming changes. The PIMs allow quick and easy broud changes.

"PIM changes basemap also. Does it change basemap before fuel correction map is taken into account? Or I guess it just adds/subtracts to fuel map. " It adds or subtracts in conjuction with the FCM.

"Why have all these adjustments? seems there should be no basemap or just a basemap of 1. Then that could be adjusted. " Allows greater tuning flexibility for those who understand it.

"why change basemap at all? Just keep the same basemap and adjust using fuel correction& PIM?"
Easier to add x% to 1.00 than a value like 1.221 for future changes if needed. I like the STEALTH reason, your real fuel is now hidden from the commander and any peeping eyes. Plus you can see the overall fuel pattern only with the recalc base map. Notice down in P16 - P20, my max fuel is at N15, 6000 rpm. Then the fuel leans out above that. Why do you think this is so?
Because my max torque iis at 6000rpm and the engine is breathing it's best there.

Stevil

Since we are kind of on the tuning topic,
In regards to timing, why are there such wide differences(IGL and IGT) between people with similar mods? How would one go about tuning those? Should fuel be set first then adjust timing or ????
Sorry, to change the thread(well it is my thread) , but I have such a knowledgeable person responding, this is a blessing.

Thanks again,
Steve

cewrx7r1

iTrader: (2)

IGL - IGT = timing split. Mazda uses 15.

The less split, the more power produced. This works well with NA or non-turbo engines.

With turbo engines, the chance of detonation is more likely with less split, thus total timing has to be adjusted also. You have to know something about how the plug position in the rotor affects presure buildup.

I recommend you go to:
http://www.rotaryengineillustrated.com/index.html