There is no secret to tuning.
There are different ways of getting there, but there are no secrets.
There is no proprietary data. It's a bunch of numbers in a table. Everyone knows what increasing or decreasing them does.

If you don't share essential info on how your car got to be the way that it is, no one can help you make it better and there was no reason to ask anyone to look at your logs.

 

That is not really accurate. Why do you need to know his timing to be able to answer his original question?

 

Because he's getting knock and we don't know his timing.

 

You still don't need to know exactly what timing he is running. You could just counter "You might be running too much timing, try less".

1-2 count at spool is hardly knock to be worried about as well. I would be willing to bet it's not there every log.

 

My point was broader.
You can't get help without being willing to tell people how your car is set up.

 

So far he has received pretty good help no? Maybe not your help?

 

I feel like you're picking a fight for some reason.
I'm not sure what point you are trying to make.

He did get help.
If he was trying to tune his own car, he could certainly get more help.

 

Bryan / Razorlab / Other gurus -- Why do folks run the EVOs so rich compared to other cars? I thought optimal AFRs were in the 12.5 - 13.5 range, but many on this board are tuning in the low 11's / high 10's. Thanks

 

I tune both my cars to 11.5. I don't consider that rich.

Generally 13.5 is for NA cars.

I wouldn't run 12.5 on a boosted car.

 

What is driving you to tune to 11.5 (textbooks, training, racing experience, etc.)? I don't mean to sound like an a$$ but from everything I have read and seen on race cars, optimal power is much leaner than most are running on this site. I am not an expert in this area and have placed a call into a few friends in Cali that are...that said, I am willing to listen to Bryan and others that have been tinkering with the EVO for a while now...Thanks for your help.

 

I have not seen an increase in power enough to warrant running higher AFRs on 91 octane gasoline. A couple horsepower or so or even 10whp is not worth it in my book. All it takes is a little bit worse gasoline on that one fill up and bad news bears.

If you live your life a quarter mile at a time and trying to eek every last ounce of power out of the car, sure. Just know the possibilities of damage are increased.

On my personal evo, in which I push the boundries instead of on my 'customers' evos, since I know I am monitoring it all the time, I have seen a couple whp increase by running closer to 12 AFR on 91 octane.

I just don't think it's worth it on 91 octane. I can't talk much about 93 octane as I haven't tuned that much with it. On 100 octane or over, it can be a totally different ballgame and of course, you can tune for higher AFRs which do bring larger gains in power, coupled with higher boost and timing.

I've seen AFRs stray a couple points gas fillup to gas fillup, different driving situations, weather changes, etc. Not being tuned to the utter limit AFR wise affords the car to run safely but still powerfully in almost any situation the user finds himself in.

I'm in the street and road course tuning train of thought because A. The street is where most people drive their car, most of the time and B. The road course is the ultimate proving ground for a good all-around safe and powerful tune as the car sees almost every single possible load, temp, weather, and gas possibility. If a tune doesn't blow up a motor on a car on a road course, I doubt it will anywhere else.

This is all IMHO of course. Some people have different thoughts on this, and well, they are other people.

 

Thanks Bryan...If it is only a few HP then tuning at 11.5 vs 12.5 - 13.5 makes perfect sense.

 

We'll thats one way of looking at things, but I can pretty much guarantee you that the guys who last tuned my car feel differently. I'm 99.9% sure they would not appreciate me posting their timing tables etc., and so whether or not I believe the data is "proprietary" or not, I'm trying to respect their wishes.

That being said, I'm trying to learn as much as I can from folks more knowlegeable than I. I realize that the data that I have presented is somewhat incomplete, but I think that there's plenty of tips I can pick up from the data presented.

Thanks for posting your timing tables btw, it does help to see the kinds of numbers that others run.

 

12.5:1 is the optimal burn for best power. But there are other things to consider, like how much boost you are running, cylinder head design, timing advance. The Evo has very high boost and a lot of timing advance stock. And it is possible that it is not blessed with the best head design to reduce knock (I am not sure about this last one). That is probably the reason why the optimal AFR is 11-11.5:1 on pump gas.

 

From reading, I know that an "optimal" AF on 93 octane is higher than 11.5. However, I tune for a little bit of a safety net should something go wrong. Different gears on my car go leaner and richer. It's about personal preference really.

I thought the same as you....watching people post about how their AFR's are in the 10's and wondering why they think that's ok.



You know, if you don't tune the car yourself, it's hard to understand.
No two cars are the same. Even with the same equipment on them, the need to be tuned very differently.

You can toss a timing map up if you want...hell you can even list your mods. However, someone's gotta be pretty dumb if they simply copy it, load it and go.
Every car needs adjustment.

I have tuned very similar cars with widely varying injector duty cycles as well as timing. Why? Simply because they are different cars.

I think what people forget is that these maps are simply 2 dimensional charts.
It's just data.

If I write something rather interesting on the internet, I don't charge people for reading it. That's my take on it. I know a bunch of people disagree but personally I'd rather offer up as much info as I can so I can help other people learn...and hopefully other people are inclined to do the same.