If you can post your tune and some logs of your car you can probably get some help. In all the cars i have done the one things thats for sure is no 2 cars are the same. What works for one person isnt gunna be dead on for you your gunna have to change things.

 

Seriously guys...read this:

Stoichiometeric AFR

Scroll down a little ways where is actually discusses AFR.

There is nothing wrong with me trying to compensate for advanced timing by adding more fuel to prevent knocking. Is there a better way to do it...I'm sure there is. Have I gotten to the point where I know exactly how to do that??? Not yet, but like I said before...at least I'm trying.

I'm sure at one point, y'all were the "noobs" at this and had people questioning your judgment on a tune. Instead of basically calling them an idiot, why not offer a firm piece of advice that would help them see what they had done incorrectly and then how to fix it.

 

were you knocking at part throttle, idle or WOT? There are ways to add/remove fuel without touching your stoich parameter. That stoich parameter as stated is involved in every aspect of your fueling.

 

at WOT only.

 

not 100% sure but I think that if its only at WOT you would change the PE

 

yup...stoich/pe multiplyer=commanded afr at wot basically...there are more factors but those are the main ones.

 

For wot fuel changes, the 4 most common ways to adjust would be Fuel injectors, PE modifier table, VE tables, or MAF transfer table.

Each have thier benefits, and each have thier downfalls.


One rule of thumb, If you didnt change it, then it probably shouldnt be messed with.

So dont screw with the IFR if you didnt change injectors, or dont change MAF if you didnt mess with the pre maf airflow.

 

Guys, you have flamed me in this thread and that's ok, I'm not mad. However, I have installed the wideband O2 yesterday and have some interesting numbers for you.

You say that if I change my stoich, then I'm running rich at all times. This is not true.
You say that I don't know what I'm doing even though I showed you mathmatically that with the ethanol in our gas, we can change the value and not cause problems.
Then, I'm told that I just got lucky... Well, I don't think so.

My cruising AFR is around 14.3 - 14.9 and even into the very low 15s when I'm giving hardly any gas on the highway. As I start to give it a lot of gas, it drops down towards the 13s. When I floor it, it drops to the 11s for a brief second and then climbs back to the mid 12s and holds steady...NO KNOCKING.

My car pulls very strong, I'm not getting any knock and none of my sensors are freaking out...no knock retard coming on, even at 70 degrees out side with my timing advanced a lot.

 

That number is for the TARGET air fuel ratio when in closed loop. If your vehicle isnt going into closed loop or if your tune is way off, or your O2 sensors are old and slow would be the only way that the averages read on your wideband would be in the 14,s

If the computer Commands a set value when in closed loop it will use 02 feedback to get the desired value.

 

I should be in closed loop. There's nothing wrong with my O2s...the car runs fine. The car only has 33k miles on it.

From what I can see, based on my tune, when I hit WOT, the car is targeting that number...the wideband is saying so. Granted, it's about 4/10th of a point off, but I suppose it's better to be on the rich side than lean side.

If you increase the spark, you should increase the fuel right? Is that not what I have done? Would not having cats contribute to anything?

 

Man i havent flamed you this whole time i have simply put in a comment that was important to the conversation. BUT STOP TELLING PEOPLE YOU MADE CHANGES THE RIGHT WAY. If it worked for you great you got lucky its not going to work for others that well cause thats not how it works. Also timing is something that shouldent just be increased wildly there is a point of deminishing return how much did you add did you add it to the whole table or just part of it?

 

I have not flamed you, actually I apprecieate the fact that you posted your tune. Most if not all who have replied to this thread disagree with your tune, but no one else has posted one for us to look at.

From what I have read in other post, you most likely have your tune working right but you had to mess with a lot of other factors when you lowered the afr. Some might say its wrong, it does not matter I guess as long as your happy with it and you feel your car is running safely.

With help from RussK on HPT site, this is my most recent tune. I dont think it can be made any better until I get a w/b 02. Good luck with your set up and let us know what you do at the track and dyno.

 

All I said is that I have a tune that works well (for me and others I've given it too). Never once did I claim is was the perfect way to do it or that any joe shmoe should use it without reviewing it first...
It was mostly MeentSS that was doing all the smack talk. I never once told "martha" to install this tune on his car, "he's going to love it" sort of thing. He asked to see examples of tunes for our cars and I showed him one. Doesn't mean he is suppose to use it and yes, I agree, what may work well for one person may not work well for another.
In my original reply to this post, I said i created a "beastly" tune for MY car, and then I uploaded it so martha could look at it and review. Then I start getting all this flack about "here's what's wrong with the internet...morons claiming they know stuff and offering advice when they don't know anything about anything" kind of crap.
Like I said, I'm new to this stuff, but I'm learning and I'm trying. I never asked anyone to develop a tune for my current setup because I'm too lazy to do it myself.
I disagree with what the majority of these guys have said about tuning my car wrong. The fuel I use anyways, is an Ethanol blend so I don't see anything wrong with changing the stoich. Based on the numbers I got using the Wideband, (which is installed correctly) the car is 100% FINE!

 

To answer your question 98red, I carefully went in to the spark advance table to add timing to various parts of the chart. It took a lot of time and data logging to get it right IMO, but I did it. The entire chart is going to look different. If you own HP Tuners, look at my tune compared to a stock tune. There is a BIG difference.

 

one thing you might wanna consider is not having your high & low match identically...usually in my wot area I'll take a few * off so if I do get a bad tank of gas im not knocking all over the place

I think the biggest problem you'll face when changing stoich is that it intermingles will all your other tables such as PE multiplyer...currently with that stoich afr set to 12.8:1 your multiplyer at say 4000-4400 is 10.77:1, and at peak hp on your car ~5600 rpms your commanding 11.07:1 afr.

Now I don't speak for all of us out here, there are some that tuning using the IFR/pe tables or others, but generally to make it I guess you can say easier on ourselves we usually aim to get our commanded to equal our actual afr...its a simple process & really doesnt take much if any more time at all.

Im glad things are working out for you & hope they continue to work for you & its great your thinking outside the box, but if you know your shooting for a 12.8:1 afr why setup your commanded to be 11.0:1? Anywayz happy tuning.

Bill

ps-im sure we'd all love to see any logs you have to see how everything else in your tune is working together-this is not a bash, personally I've never changed stoich so I would love to see its affects on trims, IDC & so on.