I just got my wideband hooked up and it is logging properly but I don't have a target AFR map to shoot for. I know around what I want on each section of the maps but I was wondering if anybody had a conservative AFR map that they saved that I could use to shoot for.

 

i could use one of these too. it looks like we probably want 14.7 in the idle and vaccuum areas and 11.0 in the high boost areas, with a gradient in between. but i'd love to see P/N table filled with good numbers to shoot for.

if you got any pm responses to this thread, please send them my way.

 

You do not need a fuel base map except maybe to cut down on tuning time. As far as the "TARGET AFR", that is up to you to decide what levels you are willing to run. Many post here and in thge single turbo forum discuss this and timing.

If you have a wideband and DATALOGIT, that is all you need. Where do you think most current maps came from? They came from us starting with stock or mod base maps and tuning them ourselves.

Just add extra fuel and start logging. Then adjust and start over again.

To get a good starter map, the doner would need to have an engine setup almost exactly like yours in porting, and matching complete fuel delivery system.

When I only rewired my fuel pump with no other changes, I had to retune everything above about 10PSI due to the 2 volt increase to the pump.

So be brave and go to it.

 

i'm not looking for a fuel map or a correction map. i'm talking about what afr readings i want to tune for in each individual cell. i read one of your posts, chuck, where you recommended tuning for p10 and below, and then scaling down to 11.0 at p17. but you didnt mention anything about n columns. do you not want to run richer at high revs too?

also, do i really want 14.7 in the deceleration cells (p2-p3)? i'm reading free air (20.9 on the innovate) in those cells right now. that seems fine for regular decel or downhill coasting, but what about in the upper rev range? do i want to try to add fuel there?

what i'm looking for is a 20x20 p/n map that shows what a properly tuned car would log for afr's in each cell.

perhaps there are more resources available on the datalogit group. i sent my email to register when i got my datalogit (many months ago), but i never received a response. is there anything else i can do to get access to that group?

 

Ideally you can tune simply for load (say for the 800rpm column) and then replicate those settings across the RPM range.

 

For decel you want it to read free air when the injectors shut off completely (decel fuel cut). Controls for what RPM the injectors turn back on on a decel is in datalogit right above the idle settings.

 

I adjust idle and cruise not by AFR, but by leanest smoothness. I do this to increase mileage and reduce fouling. This takes more time than the boost or transistion regions.

As you said you have read my AFR tuning notes and you have that area.

Next you have to decide about the transition area, about P8 to P16. Two ways to do this. Taper down from 14.7AFR to your P16 AFR, or tune it all for max power at about 12.1AFR. The taper is cleaner and better mileage, the last is slightly better spoolup. Your choice.

If you read multiple articles about AFR tuning (even for piston engines) and then think about what you are trying to do in the different regions, then you should be able to know more.

 

My advice is to hook up with someone local to you that has an equal interest or some experience with the datalogit and get started, slowly. AFR targets are really an art but you can simplify it for starters and then experiment, read, and experiment some more. If you spend days reading the posts on this forum you will gain enough knowledge to set your own AFR targets. Here's a short answer: tune idle for smoothness and forget AFRs, tune cruise for smoothness and AFR should be in the 15 to 17 range but you may need to play with the accel enrichment settings to get it to not stumble when you roll into the throttle, tune boost rows for somewhere between 10.5 and 12 based on your fuel/boost level/timing/ignition/and risk aversion. Once you get there you will see if you get any knock during spoolup plus you will see any areas that don't look right and you will fix them, it's simple really but takes a ton of time which many do not understand.

 

These are some of the ones I've tried. I think column "E" is to lean.
AFR-A B C D E
-27 P1 13 13 13 13 13
-24.1 P2 13 13 13 13 13
-21.2 P3 13 13 13 13 13
-18.3 P4 13.5 13.5 13.5 13.5 13.5
-15.4 P5 14.2 14.2 14.2 14.2 14.2
-12.5 P6 14.7 14.7 14.7 14.7 14.7
-9.6 P7 14.7 14.7 14.7 14.7 14.7
-6.75 P8 14.3 14.3 14.3 14.5 14.3
-3.85 P9 13 14 14.2 14.5 14.2
0 P10 12.0 13.2 14 14.5 14
0.95 P11 11.9 12.9 13.8 14.3 13.85
2.37 P12 11.8 12.7 13.5 14 13.7
3.8 P13 11.7 12.5 13.3 13.7 13.5
5.2 P14 11.6 12.3 13 13.5 13.4
6.64 P15 11.5 12.2 12.8 13.2 13.25
8.06 P16 11.4 12 12.6 12.9 13
10.9 P17 11.5 11.7 12 12.2 12.75
13.75 P18 10.9 11.3 11.5 11.8 12.4
16.6 P19 10.8 10.9 11 11.2 12.1
19.4 P20 10.5 10.5 10.5 10.5 11.75

 

This didn't paste well at all. You will have to seperate the rows into seperate columns to read them correctly. Or I can send you an Excell sheet that will make automatic correction predictions.
Barry

 

i've made up my own spreadsheet, but i'd like to see what you're using. please send to pi_striker@hotmail.com .

for mine, i just paste the logged afrs from the map tracer into a table, and divide each cell by its corresponding cell in my target map. this gives me a map of correction values that i paste into the inj correction map after recalc'ing the base.

i've learned that while this may eventually converge on a suitable map, the iterations are a bitch. i've also noticed that the pfc doesnt just read from the cell you happen to be on -- it it clearly pulling data from neighboring cells. (there are hints to this behavior in other threads on the forum.) this causes problems when there poorly tuned cells nearby the cells you are tuning.

it would be nice if there was a tool that smooths your base map as individual changes are made. if i can come up with a better excell sheet, i'll share it here.