Learning How to Tune: Starting with the basics?
 

What's up guys..

So I'm just wondering what types of resources are there as far as learning how to tune for people starting out in this area?

I've read the quick start guide on the manual for my Haltech Sprint RE and I'm always reading the tuning guide in the "Help" section on the ECU Manager as well as threads in this section of the forum, however, I'm still finding it hard to "learn" how to do this stuff.

I installed an E6X in my last setup and it started right up on my first try and idled pretty decent. However, it wasn't very driveable and I never got it very driveable because of my lack of knowleadge with the unit. I'm wanting this to change with as I've got a more expensive setup in the overall car. I went with the Sprint RE because of it's simplicity mostly and I don't need all the extra inputs and outputs of a PS1k or PS2k. I will definitely have this setup professionally tuned as I'm not willing to risk blowing my engine up to "learn", however, I would like to have knowleadge to know what a tuner is doing with my car or if I have to troubleshoot, know what I'm doing and what to ask or know what someone is saying when answering one of my questions.

Main things I'm wanting to know about the specific Haltech software are:

1. How do you compensate for different injector sizes? Or is there somewhere I missed in the software where you put in your specific injector sizes, base fuel pressure, etc.?

2. What is Load in KPa? and why is it in decimal format? Is it Lambda? Do you convert it to stoichiometric mixtures? If so, what formula would I be using? For instance, what or HOW do you read this map and make adjustments??

Attachment 712964

Obviously, the left hand column is RPMs in 500RPM increments, but what about the top horizontal row? How exactly is that read?

3. Under the "ECU Navigator", which tables would be mostly used for fuel and ignition? Are adjustments made to all of them? I like how when you hover over them, it gives you a brief explanation of what they do. Very helpful..

4. What is VE tuning vs. Injection Time Tuning and is it just different maps that you use that determines your tuning method or is it an option to choose which type of tuning you'll be doing in the software? Or maybe just a different method for coming up with calculations using the same maps? Which type of tuning method is.... better or maybe more simple to use?

I have more but that's where I feel would give me a good start.. I'm not asking someone to sit down and go over EVERYTHING with me.. Just tips and maybe resources that I can read up on as well as different stuff I can play around with on my desktop version of ECU Manager.

Sorry for sounding like a complete n00b, but I most definitely am when it comes to this side of the court. We all start from somewhere though, right? :)
Thanks in advance for any help. :icon_tup:

http://www.amazon.com/Engine-Managem...2747395&sr=1-2

http://www.amazon.com/Modify-Managem...2747423&sr=1-1


Those are links for the two best books I've read on the subject. They'll give you a good, basic description of how all the sensors work, what the ECU sees as and inputs and what it does for outputs, what the fuel and timing maps represent, and how to use a dyno to tune. Read those books and you'll get more information than you would if you attended one of the popular EFI-101 courses.

To answer your specific questions:

1) Haltech only allows you to use pulse width tuning when using doing staged injection. VE can be used on standard, non-staged setups. With pulse width there is no need for the ECU to know the injector size or fuel pressure as you are programming actual injector on time in an RPM v. load matrix. Go to a different size injector and you will need to change the values entered in the matrix or do a raw, percentage based offset.

2) kPa is kilopascal, absolute. That's what it should be, but in Haltech speak it's not an absolute measurement but a gauge measurement and should be noted as kPg. At any rate, it's a metric atmospheric pressure measurement that, like all metrics, is easy to work with but is unfamiliar to most in the States. You can change all of the units to English if you prefer. Click Tools > Options and change the settings as desired.

3) The base fuel map is just that. It's a table that should represent what the engine wants when it's at operating temp and in a more or less ideal running condition. Same for the base ignition map. All the other tables are offset tables that alter the injection and ignition outputs based on conditions. The engine needs more fuel when it's cold, so the coolant correction map alters injection pulse width based on coolant temp. Same for air temp. When the air is cold you need more fuel. Read the books in the above links for a better description.

4) Again, with the staged injection used for most rotarys, injection time is the only option you'll have with the Haltech. Some prefer VE, others injection time. With VE tuning you program an a/f curve and tell the ECU the injector size. You then program the VE curve of the engine. With this information the ECU can determine what the injector pulse width should be. With injection time you simply program the injector pulse width in the base fuel table instead of letting the ECU do the calculations. Neither is better or worse in the end, and both require similar work to accomplish the end goal.