Thread: Why I tune to 12.0:1 A/F ratio (0.82 lambda) and why you should too. (all welcome)

How long would my engine have to last running high boost at 12.0:1 to change your mind?

Ben, it is like talking to a brick wall with some peeps man. Just keep doing your thing. I always have tuned to 11.8-12.0 with no issue.

Brent

FWIW 60k miles (motor had 70k miles before turbo) with stock RR motor (thin ring lands) with S3R cams and 14-16psi. Everything was in perfect shape when I took it apart. Tuned to 12.0:1

Buddy took them and put it in his motor and they last 5 miles (literally he went to highway got into boost and it was done) on his tune and the ring lands broke with detonation. His tune was rich 11:1.

So obviously the extra fuel prevented detonation

I'm not really arguing the point that you can't run 12.0 afr and be ok. I'm just stating that in my experience (tuning DSM's), I have always prefered to add timing to make power, as opposed to leaning it out.

The extra egt's should help combustion, no? I'm curious, and just trying to learn something. Although it may be wiser to collect my own data from the internet. But it is still kinda "hearsay".

There is a lot of BAD information on the internet especially tuning related.

Tuning is a science not a black art like a lot are making it out to be.

You can tune however you want. My point is that 12:1 lasts and works great and richer doesn't mean safer.

^^^^^You are with me^^^^^ I prefer to ad 2 deg and get 20 whp than back up the timing and lean the mixture and gain only 10whp jejejeje I dont want to tune my car here in the tropic that lean... I ve been there it in the past and I dont want to go back....

This is why you are both retarded. It seems you understand nothing about the science of an engine. I don't understand how anyone would let people like you near a car. Or rather I do, because like 95% of tuners are complete idiots.


Timing determines when you initiate a combustion event. The AFR relates the to flame propagation. So with the two you can control torque output of the motor.

By advancing timing and enriching fuel, you are getting back to where you start since you start the combustion sooner, but your flame front is slower.

And the extra fuel does nothing too cool the charge, as the latent heat is poor (if you even understand what that means).

Get a clue.

And another important item to point out, when you retards think you are being safe by adding all this extra fuel, you actually increase the likelihood of damaging knock. Stupid rich means more unburnt fuel, which causes a huge problem if another combustion event occurs after the primary. Most likely the cause of wnwright's friend's demise.

I don't appreciate being called retarted for starters. I was learning more about the topic. I just stated what I have found to work well, on cars I have tuned. Maybe dsm's are different, I don't know.

Doesn't a slow, controlled burn create more ? Is this not why people run racegas?

I have too much of a life to understand what latent heat means. Maybe something to do with the amount of heat is absorbed or something? I don't know, could you elaborate? Don't get too technical with it though.

How much difference is there in running say 11.6 vs 12.0 afr? I mean, I don't know how much power difference you would see from this. Is it really THAT serious?