Everyone keeps saying tuning with EGT is not a great idea. Whenever I have asked 'why' I didn't get any answer.

Since I know I am on a rich side of AFR I could use EGT gauge to fine tune my fuel map and also know when I am knocking.

If you want to know why am I so stubborn to use EGT it's becuase with 10.5:1 compression pistons I really don't know what is the safe AFR for my car. Before I thought it was 13.1 but I have reached even leaner conditions without knocking.


Can someone give a solid reason to stay away from EGT?



This is a setup I was going to do:
Low mass, fast responsive EGT Probe. from www.zeitronix.com
http://www.42draftdesigns.com/produc...wb-114-400.htm gauge.

 

buy it... i plan on getting one... even if you dont use it too tune... if you ARE tuning you car yourself it will be a nice thing to watch to make sure you dont melt anything. Which is what im going to do once i get some more cash together.

 

you should get the wideband and the egt... that's the best way. Wideband lets you know exact afr... and the egt lets you know if things are getting to hot.

 

You don't tune with EGT because 1. it's less accurate at determining AFR than getting a direct AFR reading, 2. it's slower to change than an O2 sensor reading 3. temps go up when you're too lean, but they also go up when you're too rich. It's great for reference, but it's not wise to tune any car by EGT alone. I certainly wouldn't say to "stay away" from EGT, but I also wouldn't rely too heavily upon EGT by itself.

Yes.

 

Thx a lot for your opinion Andrew. This is what I was looking for.
What about EGT + narrowband combo?

 

You could definitely get somewhere with that, but I still wouldn't count on it for precise tuning. The bottom line is if you want precision tuning, you need a wideband O2 or UEGO.

 

How then I would know my max AFR before pinging? Would I just have to start pinging and then add some fuel?

 

With a narrowband...you wouldn't. You'd just create reference points in temp and whatever the narrowband AFR gauge gives you. Then you tune from there. It would not be the ideal situation.

 

even with wideband you tune much in the same way... people try to reach a common afr but if pinging occurs they add in fuel. Often you'll find tuners with advance timing and lean out fuel to a point where the ping occurs then add it back from there. After doing that a bunch of other pulls occure including a good couple of heat soak pulls to ensure the pinging is taken care of. If not another slighter adjustment is made.

 

Do piggybacks read the Lancer's knock sensor? Because I wouldn't trust an ear to measure knock by itself. I'm not trusting enough to tune this car by EGT. With something like a DSM where temps have already been widely learned and studied...maybe. But in the case of the Lancer I really wouldn't advise tuning by EGT alone.