cfwthb_94

I have a good basic knowledge of how to tune the fuel aspect, but lacking the knowledge of ign. timing. I'm using a s300 and would like to see other's ign. maps so I can try to study them and learn from how a good map should look like. I know every car is different and every setup is different, but it will still show what a quality tune should look like and how everything transitions into the next cell. Thanks for any help you can give me or point me into the right direction. I do plan on taking the Efi 101 basic class next spring.

sander

Just read a little bit about why timing should change at different load points, and keep in mind that the smoother your tables are, the less work the ECU has to do to interpolate the data between really crazy jagged 2d tables and that "can" help the timing value be more consistent and regular.

cfwthb_94

I have an understanding of the interpolating between the differet break points, and also that the higher in the rev range the less timing you need. Could you point me in the right direction to start looking for information. I've tried on here and came up with little quality information.

sander

Why is this? Are you sure thats correct? What happens in the cylinder when you increase or decrease timing generally speaking?

After peak torque do you want to increase or decrease timing?

Those are questions you should go after. I won't answer them for you, as you will find more information than I will provide over the internet, in a book.

http://www.amazon.com/Bosch-Fuel-Inj...8269974&sr=8-4

I like this book alot, and its fairly cheap. Good basic principals.

cfwthb_94

I believe I read an article that Mase did on here from like 2004, about the less timing after peak torque and higher rpm.

I've put that book into my wish list on amazon. I ordered another book off of there. Engine Management: Advanced tuning. We'll see how much I learn from that one first.

Thanks for the help Sander.

sander

That's an excellent book too! And the EFI101 classes are awesome. Ben has done an awesome job putting together the curriculum (spelling, sorry) for that class.

cfwthb_94

I saw that he wrote a book, but for the life of me I can't find it, the guy from efi101. I plan to get about 3-5 guys with me next spring to go take a class hopefully. I love learning especially when I'm not forced to and it's something I'm interested in. lol

98vtec

http://forums.evans-tuning.com/viewt...gnition+timing

This article made everything click for me way back when

Just remember that it takes time for a spark plug to fire and the full combustion process to occur. this is why it starts as the piston is still moving up.

About the ignition timing, do your research on MBT tuning and you will find your answers. But mostly, you will find your answers back putting theory into practice. Theory really goes out the window when you are tuning a setup that doesnt abide by the laws. If you add timing and it loses power, lower it. learn how to read spark plugs. They are your BEST tattle tales for knowing how much is too much or how little is too little.

also, dont always take the little numbers you see in the map as the bible.

cfwthb_94

I've been trying to find out what MBT stands for and for the life of me I haven't figured it out what it stood for. And reading spark plugs is something I lack in what to look for and what it tells you about what's going on. I remember attending an IFO event a couple of years ago and tony1, after every run, would pull the plugs and look them over.

98vtec

maximum brake torque. basically your ignition 2d graph with be a rather "steep" upward slope to peak torque and then it will basically plateau. At this point you slowly increase timing until power falls off from the additional timing advance. You can catch a bad timing advance before it is too late by reading the plugs each run. Click the bbmoto link in my sig and go to the wiki. There is a link at the bottom of the wiki regarding reading plugs. If the engine doesnt like a timing advance, try retarding the timing. It really comes to trial and error and watching the dyno graph.

Once you look that up, read up on lean best torque and rich best torque. But really, you can throw all these theories out the window if you can read plugs. Do what the engine wants.

cfwthb_94

Wow that was pretty clear I actually understood everything you said, I'm proud of myself. lol Thanks for the help and pointing me in the right direction, very grateful.