R U A LS1

I read this typed by BfB in a search i did about the preditor tuner.
In actuality, if you would have raised timing instead of leaning the vehicle out, you would have effectively leaned your vehicle out on top of most likely gaining more hp/tq, that is if your vehicle would have allowed the additional timing. I've proved this on multiple LS1's, and also I did the same thing that you did on 2 other LS1's and managed to best the hp/tq by using timing only instead of leaning the vehicle out w/ just the fuel trim setting via the Predator.
Now i'm a little more than a novice when it comes to tuning but im still learning. Im not sure i understand this...leaning and richening your AF is the same as advancing or retarding timing? then why is messing with the timing giving you more power? I don't get it. <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" />
I also don't understand that if you want the AF around say 12.8:1, why not just mess with the AF and get the HP...why would you get more getting the 12.8:1 with the timing if a 12.8:1 AF is a 12.8:1 AF no matter how you get it. ugh, that's about 23 questions for you guys. <img border="0" alt="[Banging Head]" title="" src="graemlins/gr_banghead.gif" />

SSpray

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NoGo

iTrader: (2)

Rich / Lean / Timing are all related. The richer you run your engine, the more timing advance you can run. The leaner you run your engine, the less timing you will be able to get away with.

Typically, more horsepower can be made by getting an exact a/f ratio rather than running lots and lots of timing.

Good Luck,
Kevin

R U A LS1

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by NoGo:
<strong>Rich / Lean / Timing are all related. The richer you run your engine, the more timing advance you can run. The leaner you run your engine, the less timing you will be able to get away with.

Typically, more horsepower can be made by getting an exact a/f ratio rather than running lots and lots of timing.

Good Luck,
Kevin</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif"><img border="0" title="" alt="[Roll Eyes]" src="images/icons/rolleyes.gif" /> right <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" /> , so now my AF is an 11.5:1 pig. I read what he said, but still didn't answer the question of a MAFT or timing tuner, given my AF ratio.

Z2late

I'm with you R U A LS1. I'm not too sure any body understands on this site. The more they ask the more they confuse themselves. A/F always has and always will stand for molecules of air to molecules of fuel <img border="0" alt="[Banging Head]" title="" src="graemlins/gr_banghead.gif" /> It has NOTHING to do with timing. To answer your question buy the Diablosports Predator and fine tune on the track.

NoGo

iTrader: (2)

Timing does not change with fueling. It is an independant adjustment. However, the air to fuel ratio of the combustion mix determines specific boundries for timing.

Here is how the molecules, as you so clearly stated, relate to combustion timing.

We can all agree that leaner = hotter, richer = colder. If you don't agree, then don't even bother reading the rest.

Leaning and richening the combustion mixture affects the combustion expansion rate. This is easily proved with bournoullies(sp?) principle

Pressure x Volume = Mass x R x Temperature

If you increase the temperature of combustion you are going to increase the pressure and the volume of the gasses. An increase in pressure and volume means an increase in the expansion rate of the cylinder gasses. A faster expansion rate of the gasses means a quicker moving pressure front in the cylinder.

Now for timing. Timing is the PCM's attempt to detonate the combustion gasses so that the pressure front of the combustion acts upon the cylinder as the cylinder is 10 deg past Top Dead Center. The combustion is ignited before the piston reaches top dead center in order for the pressure front to act upon the piston at 10 after top dead center. The amount of timing in which you ignite the mixture prior to TDC is called ADVANCE.

How they are related.

If you have a slow moving pressure front in the cylinder (a cold combustion) then you must ignite the mixture much earlier otherwise the piston will reach TDC and travel much farther than 10 deg down the stroke before the pressure front finally catches up.
If you have a fast moving pressure front in the cylinder (a hot combustion) then you must wait to ignite the mixture longer. If you do not reduce the advance then the pressure front will move so fast that the piston wont even have a chance to make it to TDC and the two will collide in opposing directions. The piston will still be traveling up and the pressure front will be traveling down. When the two meet BOOM, detonation.

Sooooooooo, you cannot run as much advance on a lean engine. <img border="0" alt="[judgement]" title="" src="graemlins/gr_judge.gif" />

<small>[ November 27, 2002, 04:12 PM: Message edited by: NoGo ]</small>

NoGo

iTrader: (2)

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by R U A LS1:
[QB right <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" /> , so now my AF is an 11.5:1 pig. I read what he said, but still didn't answer the question of a MAFT or timing tuner, given my AF ratio.[/QB]</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">BfB is wrong. You cannot gain more HP by tanking the cars a/f ratio and taking timing to the moon. It is an intertwined ratio of the two that will give you the most power.

You need to get your a/f to 12.8 FIRST, then set your timing. Advance your timing until you encounter KR, then take it back 2 deg.

Z2late

NO-GO is 100% right about all of this. Except for the 10*ATDC part. I'm almost positive it supposed to be between 14* and 16* ATDC for maximum cylinder pressure without detonation. But NO-GO seems like he might have the best answer for you. <img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />