Updated the first post with graph.

Also putting it here because you bastards are lazy.

 

nice work now we just need to strap someone to a dyno and figure out what the middle of the best power bands are (but I think we've guesstimated 12.7 ? )

EDIT: I actually followed the link, printed the graph and did some reading.... I'm not the bastid you was talkin about though, right

 

I knew I had it printed in one of my ringed binders of tuning and parts info, but that meant 1. I'd never find it and 2. I had no idea where it came from.

Didn't wanna steal the pic cuz I figured they'd catch on, and I need their tuning advice.

 

Well, tuning A/F ratio should not be a noob thing to do. There is some good noob information in this thread though, so it wouldn't make sense to change the title. Guess we need to just start asking more noob-like questions.

 

Here is my contribution:

Let's say I paid someone to tune my Emanage. Everything is working great. I decide to buy an exhaust manifold, 2.5 exhaust, and a bored fuel rail, would I have to get it retuned?

It would benefit me since now my horsepower and torque and A/F ration curves will change but would I be able to drive me car "SAFELY" without tunning it?

 

Probably be wise to have it retuned. You'd suddenly be exhaling a lot better, which probably changes the engine systems quite a bit.

 

First, I'd verify that the eM tune has held. Get on a WBO2 and make sure that if you tuned to 13:1 you're still at 13:1 I've noticed that mine will creep back to 12:1 within a day or so. I'm working on it, and I don't know how common the issue is.

Now, if you're still holding the map, you probably only need to add a very little fuel. I wouldn't use the main A/F map. I'd turn on the additional injector map and have the injectors add maybe 0.5% fuel in the spots it leaned out a little. It won't need much, and the ECU doesn't really see these inputs so it won't learn around them. Too bad you can't tell the injectors to add less fuel

In theory, you're now able to better extract exhaust from the cylinders, you won't have the unburnt fuel to act as a buffer during combustion, so you'll need a little more fuel to absorb some of that heat and to fill the void left by the unburnts.

Of course, the 2.5" exhaust is too big for an NA application and may not extract as well as a 2.25" or even the stock system does- you may not need to make any changes at all

 

My guess, is you will be fine and only need to tweak your fuel map slightly to get your new mods to work effectively.

 

Again, I'm gonna claim that until someone shows me a dyno proving otherwise, the 2.5" exhaust is the ONLY dyno proven gains we've seen from an exhaust on the Lancer. The test was done with only intake and exhaust.

 

I sort of want to stick with 2.5" because the header is 2.5". My exhaust is purring like a puss with high compression pistons (stock exhaust).

 

all the more reason to go to 2.25" You'll be squeezing the gas out of the exhaust system by increasing the exit velocity at the exhaust tip. That basically means more exhasut is escaping the system, so less of it will be in the cylinder when it's time for combustion.

Since this is an AFR thread and I've practically written a book about this with SDHTown (search for the exhaust threads from 03-04) I'm gonna stop discussing exhaust.

 

Sorry for bringing this up ^


Now I am concerned about buying the eM since engineerboy's ecu is refusing to work with eM.


How about a little summery?
When you are tunning eM with a WBO2 do you want to stay as much as possible at 12.7?
If 12.7 would have been at every rpm point would that mean best HP gain?

 

Here's the recap: I'm the only one I know of that knows for sure his eM isn't holding a tune. I'm also the only one I know that's using an actual WBO2 and other data gathering devices (PDA scan tool). Dave at RPW swears that he's never heard of any such thing (AUS ECUs and US ECUs must be different because of our stinkin California emissions regulations). He also says he mostly tunes with the additional sensor map- but then you can only add fuel, so that's great if you're a turbo guy, but I'm rich, biatch and want to get lean like Sobe. I've read from a guy on the yahoo eM group that this is common with the Evo, and I've read here that not only does the ECU resist maps, it also has problems with the MiVEC controllers. I've been told about a potential fix, but the adapter probably won't be here until Thursday (I leave for a long weekend Thurs night so no chance of getting that hooked up)
On the other hand, the splitsecond/RRM pigy seems to work fine over the long term. How, I don't know- it appears to be wired the same. They must use a different mapping method or something.


Now, as for the ideal AFR, Rhyzin (I think) posited a long time ago that 12.7 is our ideal. Boe chimed in that 13.5 was too lean and could/would cause piston pitting in Firechicken's cam thread. He then says 13:1 is about as lean as he'd go. So I'd say 12.7 is probably pretty darned close to the ideal.
How much difference does 0.7 AFR make? I don't know. What I do know is that I have over $800 worth of fuel management and datalogging equipment in my car (add the PDA and Auterra software and that goes up to about $1500) and I'll be damned if it's just gonna sit there doing nothing

So, yes. When tuning each set of circumstances (RPM vs Throttle position), you want to keep the AFR as close to 12.7 as possible across the band. You may want to richen up at 5000 to as much as 12:1 because there's gonna be a lean spot coming up and why not not tempt fate?

So if the fix works, I'll let everyone know. I don't know if I said it in here or not, but if the fix I've been told about works, you need the support tool to activate it (it runs off of the VTEC jumper because it's RPM dependent). Support tools run about $40 if you can find someone who clones them and mohdparts.com sells them for $115. So then you need either a profec ($500) or laptop to get to the parameter settings.

Pay to play, I guess

 

How would I know my timing is off???

 

Quick question, maybe engineerboy can answer this, is the canadian ECU the same as the US ecu?