I am getting my new cam, tb, and headers installed in a few days and I am going to be dyno tuning my car shortly after. I was looking over ECUflash and I was wondering what do I need to do to tune different loads?

now 100, 90, and 80 are all pretty easy to do, but I want to tune the entire powerband. What would be the proper way to go about doing this? thanks.

-Justin

 

The ECU will make adjustments while in closed loop and you're driving at partial throttle.

 

so should I only really worry about 70-80% load and up then? I just want to make sure I am getting the most out of these mods.

 

70 - 100 is the WOT area and where most of your open loop driving will take place. To make sure you get everything tuned, just log log log as much as you can while cruising around town. Run through different scenarios of part throttle acceleration. when the car transfers to open loop, the O2 Feedback Trim values will flatten out (100 in EvoScan) and that will let you know where to check your AFR values.

If you are talking about timing adjustments, there is no closed loop timing. What you put in the timing map is what the car will try to run, closed loop or open.

 

good to know.

so I when I get on the dyno, from what I understand, I should pull some timing from the top end, and then tune the a/f to around 12.5-12.7 once I hit this spot I can start adding timing until I get knock. Once i start seeing knock of less than 3 I should pull it back a point or 2 and call it good.

The only problem I really have at the moment is that I am an auto, so when I dyno should I run in drive or 3? I am thinking 3 because I believe it is closest 1:1 gear the autos have. I should also be tuning to third gear because as you go through the gears you will gradually start leaning out, so by tuning to third I prevent from running lean in my lower gears.

any other advice I would greatly appreciate. I found a shop that will swap pistons and rods for actually really cheap so I am considering jumping up in compression on top of the cam, should make for a pretty decent gain. will see though, don't want to get my hopes up to high. I am just sick and tired of running in the high 17's low 18's quarter miles. =) I know I won't be fast but faster is better than nothing.

-Justin

 

Yes, dyno in 3rd.

 

First off all of the advice that I am giving is from personal experience and by no means applies to everyone's car. Take all advice I give at your own risk and good luck tuning...
I have tuned to both 12.8 AFR and 11.8 AFR and there is barely a noticeable difference in the amount of power it produces. I'll explain later why this is...
Depending on what your intake mods are you will have to adjust your maps differently. Stock fuel maps run rich BUT they also are over advanced. Because of this, you will have to decrease timing more as you will generally be leaning out the air/fuel mixture.
DETERMINING RICH/LEAN KNOCK.
-You will have to determine whether you are getting rich knock or lean knock.
RICH KNOCK is caused by lack of timing(Too much fuel). LEAN KNOCK is caused by over advanced timing(Too little fuel).
-Log your WOT pulls and pay close attention to the areas that knock. Example: You log a knocksum of 5 @ 3500-4000 RPM with an AFR of 11.5.
-This mixture is too rich as the target AFR we are aiming for is 11.8-12.2.
-Before you begin pulling fuel you must first determine whether you are getting lean/rich knock. let's say we suspect it is lean knock so what we are going to do is decrease timing. In the case of lean knock the timing is overadvanced for the amount of fuel. So we decrease timing by 4 and log results.
-We now log a knocksum of 2(was 5 before) @3500-4000 RPM with an AFR of 11.2.
I know the AFR is now richer but you now know that we were correct in assuming that we were getting lean knock.
-Apply this rich/lean knock "test" to all RPM ranges. I "tested from 2000 rpm to redline.
- Aim for a knocksum of at MOST 3 throughtout your RPM ranges. Do not worry about your AFR yet.
-Now that you have tuned to get the most timing you can for each AFR you can now begin pulling fuel.
-General rule of thumb...decrease in fuel = decrease in timing and visa versa.
Now for the explanation of why there isn't much of a difference in tuning to 11.8 or 12.8. Considering that you tune to get a knocksum of max 3 in both situations. Your timing map tuned to 12.8 AFR will be more reduced than the timing map tuned to 11.8 AFR because the 12.8 map is leaner requiring reduced timing to keep away from knock. You may actually end up with a timing map substantially reduced as compared to the stock map. From my experience the leaner map, despite it's "ideal" AFR, actually produces less power than the map tuned to a richer AFR with more advanced timing. This does not apply to extremes such as a map tuned to 10.5 AFR or a map tuned to 15 AFR. As neither is a practical application.
some people advance timing without any ecu modifications as it does yield some increase in power despite the AFRs..

thats all i can think of right now. Feel free to add to or dispute anything that I have written.

 

What you've said is technically right, but I think your explanation of power vs AFR isn't very clear.

With all other variables not considered, a 12.8:1 mix will make MORE POWER than a 11.0:1 mix. Now, the difference is probably only a couple of horsepower, but the fuel does burn more efficiently and therefore produces more power.

Now, when timing comes in to play, your explanation is basically dead on. Using pump gas (which is knock limited), you really do have to choose between the fuel mix and the timing. In most cases, you will see more power if you choose a slightly richer mix (~11.8:1) and advance timing a little more.

However, I do disagree with your suggestion to tune timing before fuel. If you completely ignore the mix while tuning the timing, you might run in to a rich or lean spot one you start tuning fuel and will therefore have to re-tune the timing after the odd AFR spot is fixed. Also, a nice fuel curve will keep cylinder temps consistent and help prevent odd knock occurrences that could result from temp changes.

 

thats what i have been mostly told as well.
tune your afrs to whatever you want
then advance your timing untill you see knock then back off a little to be conservative

 

changing the timing before tuning the fuel reduces the risk of getting a ridiculous amount of knock when you begin pulling fuel... Stock timing is over advanced so reducing it is necessary before reducing fuel. If you begin reducing fuel your knock will go up because there is a lack of fuel for the amount of timing. When the ecu sees 4 knock or more it begins pulling timing and this causes your afrs to also change. Say we were able to run in 90% load the whole time from 3000 to 4000 rpm. And that we had the timing increasingly set from 14-17 for the appropriate load and rpms. If you get a knocksum of 11 your ecu will no longer use the specified 14-17 but will instead use a more reduced timing to back away from the knock. A timing advance of 6 or 7 may be supplemented instead. Because the ecu implements a new timing, the timing you have on your timing map no longer is used and your specified fuel map cells are no longer valid for the timing cells under consideration. So now you have to reduce timing right..simple....but reducing timing also changes your air fuel mixture, so now we also have to re-edit the fuel maps...BUT when you lean out the fuel map you also introduce knock again. what i'm trying to say is that by considering timing first it makes it easier to tune to your target AFR because you can start from a basic timing/fuel map will minimal knock, unlike the stock timing map which has quite a lot of knock, and then advance/reduce timing and add/reduce fuel from there.
It is true that if you tune with timing only you will have to readjust after pulling fuel but if you tune with only afr your ecu will go and put its own safe timing instead of using yours. Basically get rid of the knock on the stock maps so you can have nice accurate logs that use the timing maps you specify.

 

Well yeah ... I start on a Lancer by pulling about 5º over most of the map and then tune fuel. So, if you are simply saying that it's useless to tune the fuel map with the stock timing map, then I completely agree. It's would be silly to try to tune against all of that knock ... you'd end up in the low octane maps at best and possibly damage something if you pushed it too hard.

So, in simple terms, the process is:
1) Quickly build a safe timing map with no knock
2) Tune the fuel map
3) Tune the timing map

 

well what about tuning with boost. What are we looking to do when we tune with boost, because we aren't going to be leaning out our maps. Well maybe if we have big injectors.

 

When tuning for boost, the first thing you will do is re-scale the maps for the increased load. The Lancer doesn't seem calculate load the same as the Evo does, so you'll only need to scale the map to about 120% load.

Then, set safe timing AND fuel maps to start from. After that, you tune as usual, of course taking not that your AFR targets will be different for a boosted vehicle. 10.0 in the WOT area of the fuel map will be on the rich side, but should be safe for a couple of initial pulls.

Also, if you change injectors you don't have to lean out your maps. You can simply re-scale the injectors and latency values and the maps should fall in to place.

 

how do you scale it to 120? what do you put in the boxes? i never did that and mine works fine
and when you redo the injectors you put in less then what the value is in cc to keep your injectors from 100% duty cycle. by doing that you would still have to tune the ecu. i never hurd of anyone dropping in injectors and leaving it alone

 

you can add load past 100? I thought we were sol?