Dutch

Ok, so I've bought an EMS. I've installed it in my '03 Evo VIII. The base map works wonderfully, with at least as much power as stock. Now it's time to tune.

Only... I'm not a tuner, and I don't know where to begin.

Let me start by saying that I am going to learn how to do this. All modesty aside, I'm pretty damned smart, mechanically inclined, have an engineering degree, etc. I've got the noodle for it, I just don't have the experience. So, in the interest of everyone, I'm creating this thread on the AEMPower.com and evolutionm.net forums in order to create a beginner's how-to in the spirit of the "for dummies" books, which I've found to be horribly named, but "for the intelligent but inexperienced" would be a marketing nightmare, so...

I digress. Here's what I plan to do, in a step-by-step outline. I will update this as we go, so if the responses/reply posts that follow these steps don't make sense, it's probably because I've already addressed the issues that those posts address.

Note to people who want to try this, DON'T!!! This tutorial is in alpha-stage right now, and since these initial steps are utterly guess-work on my part, you will probably destroy your motor if you try it at this point. I won't be trying it either until I have a consensus that the steps are all solid, good ideas.

So, here goes. Very simple right now, I'm looking to *you* to flesh this out. I've marked my completely arbritrary guesses with (?) symbols so you will have a place to start with your suggestions. The most crucial part of this tutorial that is missing (because I can't even guess how to do this), would be all the safety cutoffs. By this I mean the rev limiters, the "AFR-too-lean-so-dump-in-lotsa-fuel" safety check, the "boost-just-went-nuts-so-dump-in-lotsa-fuel" safety check, etc...

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Fuel Mapping

1.) Rent a Dyno. Expect to pay aroung $150 per hour. Fuel Mapping should take you about one hour. Sync laptop to the ECU and find a friend to operate the dyno load and/or throttle during tuning.

2.) Starting in first gear with dyno load set relatively low, hold at 2000rpm, and adjust the fuel for the active fuel map cell so that AFR reads from the following table. Keep in mind that on the following table, 14.7psi is the "no-boost" state; our earthly atmosphere is 14.7psi.



3.) Repeat step 2, increasing rpm by 500 each time until 8000 rpm. Then repeat the whole process for third gear, fourth gear, and fifth gear.

4.) Increase dyno load and repeat steps 2-3. Repeat this until you reach a good dyno load such that you have covered/tuned the entire map.

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Ignition Timing

1.) Rent a Dyno. Expect to pay aroung $150 per hour. Ignition timing should take you about one hour. Sync laptop to the ECU and find a friend to operate the dyno load and/or throttle during tuning.

2.) Check/verify that the engine timing matched the EMS ECU timing. (Use a timing light).

3.) Starting at relatively low dyno load, do a WOT (wide-open-throttle) run, up to 4500rpm.

4.) Note the torque curves from the dyno and check the knock sensor logs

5.) Advance the timing a few degrees and repeat steps 3 and 4 until you see power level off / diminishing returns.

6.) Repeat steps 3-5, increasing the RPM target by 500rpm each time, until you're doing WOT runs all the way up to your max RPM.

7.) Read the plugs. Take the spark plugs out and visually inspect them. Here are some pictures to guide you: Spark Plug Guide

8.) Repeat the whole thing several times, increasing the dyno load each time until you're doing full-rpm range WOT runs at a good dyno load.

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Extra steps for the Tuning-Compulsive

1.) Repeat fuel map tuning now that you have a good timing map.

2.) Repeat timing map tuning now that you have a good fuel map.

3.) Repeat steps 1-2 until you just can't eak any more HP out of your motor.

EFIxMR

iTrader: (10)

one thing you'll quickly notice is that on a flat open road it will be impossible to hold it at a certain RPM while trying to reach a particular load point (psi number). the only cells you could possibly do this with is your cruise cells on the freeway. the best way to do what you're trying to do is rent some time on a dynapak, mustang or dd load bearing dyno.

Dutch

Ok, thanks. How much should I expect to pay for rental per hour, and how long should it take a smart guy like me to complete the tune?

EFIxMR

iTrader: (10)

dynotime is usually about $150 an hour. i can map a car in about two hours provided that the car is mechanically sound.

also anyone reading the chart above needs to becareful because it is somewhat confusing. 14.5 psi is actually 0 vacuum. 29 psi on that chart is boosting 14.5 psi. and ect. this is because they are counting the atmosphere as 1 bar.

if you were to try tuning this yourself, i'd atleast ask the dyno operator to watch over what you were doing. tuning cars isn't the rocket science some people make it out to be, but like any skill does require practice.

also, the ignition timing technique you posted above needs to be a little more careful. the knock sensor isn't something that is 100% reliable. the knock sensor is a good tool, but if it were 100% reliable no one would ever grenade and engine. a quick summary of how i tune ignition timing is that i do it on the dyno making slow adjustments and looking for hp and tq changes. i will also read the plugs periodically.

looking at the developing torque curve will also give you a good indication of how to fine tune your fuel map and ignition timing.

Dutch

Thanks for the great input! I'd like to use your suggestions to update the tutorial, but I have a few questions before I can:


Can you be more specific? What am I looking for here -- sporadic changes? Sudden decreases in power?


I'm not sure what that means. How do you "read plugs"?


Again, I'm not sure how. This is obviously an issue of I just don't have the experience, but maybe you could post some examples of bad curves/good curves?

Thanks again!

wreckleford

iTrader: (2)

I suggest you go on the AEM board and search for boost comp or boost compensation.

nolimits1320

iTrader: (10)

The idea of a tutorial/instruction manual on precise tuning methods is a good idea and all...but you can't teach experience. The proper way to tune is to understand as many principals of the working engine being tuned and the equipment being used as possible. The best tuners out there are willing to consisitently learn and alter thier tuning methods to achieve the best "tune". Learn the basics, practice, and don't expect to get the optimum setup with 1hr, 2hrs, or any preset amount of time. My only advise with the EMS specifically is to use a UEGO, and learn to data log.

liquidlancer

iTrader: (15)

did you read the start up guid that came with the aem? you have to understand the basic principke of an efi engine and all its components, it also tell you tell tail signs on how to read plugs
reading plugs is just basicly pulling the plugs out and checking there condition its hard to exsplain what a plug will look like but if you go into the start up guid (iforget exactly were it is) it has all pictures of diferent plugs and there conditions like lean rich preignition fouled ect.

EFIxMR

iTrader: (10)

a generalization of how to tune ignition is... that basically you datalog your WOT runs and you see what path the engine takes thru the map. advance those timing cells maybe 1 degree while watching your knock sensor and see if the changes made any difference. if your map has an dips and your af is set correctly you can usually bump the ignition timing in that spot to flatten it out.

also, your timing table under load should be smooth.

by reading plugs i mean, take the spark plugs out and inspect them. while cheap widebands have made tuning a lot easier, they should only supplement plug reading not replace it. the plug should be clean maybe slightly tanish. if its grey and has "salt and pepper" deposits on the insulator, that means you're getting some knock. if your electrode strap is totally missing, that means you were detonating pretty bad.

lots of this stuff really takes a lot of practice. one of the problems with tuning only your own car is that you don't see a lot of different setups, and experience how other engines like to run.

DrEvo

iTrader: (10)

Interesting thread, I'll be following it here and at the AEM forums.

tlcoll1

iTrader: (14)

When you say "if your map has an dips" you mean "if your torque/HP curve has any dips," right?

Also, wouldn't dips imply that the stock ECU was sensing knock at that RPM/load cell, and that you should retard timing a bit there?

Dutch

I doubt it; my stock ECU is "el-gone-o". I've done an ECU-ectomy. Ain't no ECU in da housing, fo' shizzle ma nizzle...

Ok, brief lapse of sanity aside, the AEM-EMS is a full ECU replacement. My stock ECU is sitting on my workbench. Now, if the ECU senses knock there, we'll know it, because we can watch the knock sensor directly.

EFIxMR - Please correct me if I've misinterpreted you. Also, what did you mean by "your timing table under load should be smooth"? I could hazard a guess, but I'm trying to be as concise as possible in this thread, so I'd like to delve a little deeper into why you felt that bit of advice should be shared; what are you trying to help us avoid by saying that?

Thanks everyone, by the way, this is a great thread!

Dutch

Ok, I've updated the main post's ignition tuning, take a look and let me know what you think now...

EFIxMR

iTrader: (10)

oops. yea i meant if your torque curve has dips.

what i meant by smooth is that the numbers should change gradually.

sometimes i see people post graphs of their numbers and while the peak hp is there the torque curve isn't smooth.

yes, the dip could be due to the knock sensor too. that why i used the word "generalization". tuning ignition timing is tricky. not sure if i can explain it to the depth that it deserves with a keyboard.

plus you can't really fully trust the knock sensor.

it more comes down to experience which is what you're paying for when you go to a protuner.

Dutch

Thanks for the tips!

I'm totally with you there. Only here's where I'm coming from... I want two things.

1.) Learn how to be a pro-tuner, and 2.) tune my car.

In that order.

Dutch