gwj

INteresting. Thanks for sharing the data.

NoGo

iTrader: (2)

I have been reading a few posts on here about leaning and richening setups by changing the inlet air temp resistor, or also known as a timing tricker. So I decided to do a test to see how changing the inlet air resistor really does affect the vehicle. Just figured I would share the results. All results are for WOT, done over the same stretch of road from 3000 RPM, 1st, 2nd, and 3rd gear.

Conditions: Hot Summer Day. 95+ deg F, 14.67 PSIA, 36.2% RH
Fuel: Sunoco 94 Octane

No Timing Tricker:

LTerms: 2.3, 2.3
O2's: .866, .876
Timing: 26 deg
KR: 0
Intake Temp: 100 deg F
Engine Temp: 224 deg F

Timing Tricker In

LTerms: 0, 0
O2's: .870, .873
Timing 23.5
KR: +2 to +3 across upper RPM band (4500 to 6000)
Intake Temp: 57 deg F <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
Engine Temp: 222

In conclusion, I have to say that the O2's are either inconclusive, or the timing tricker did not significantly richen up my setup. The reduction in LTerms at WOT though indicate that the setup was richened up slightly.
The most notable things are that my Knock Retard goes through the roof with the timing tricker in, resulting in a lower overal timing at WOT.

So, the timing tricker reduced my LTerms by 2, and absolutely killed my timing. I would have to say that I am loosing HP due to the loss in timing up top.

Being I have a slighly lean setup, I will probably do my daily driving with the tricker in, to richen things up a bit, and just avoid WOT runs, or get some better gas <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />

MelloYellow

The tricker or resistor changes the IAT temp. The IAT temp affects what Timing table the PCM uses. It uses the most aggresive Timing tables when the air temps are coldest at 57*.

So, all things equal it WILL increase your timing by 2-3* normally.

BUT, if you are too lean, or your engine needs to be decarb'd or you are detonating due to sucking in PCV oil.. these issues will come to light. If your setup cannot handle the extra timing, you will detonate and see KR. Or you could have cheap gas, etc etc.

It's all in the tune. If your setup and tune can handle the extra timing it's a good mod. But you can't just expect to plug it in most often. If you tune things you may be able to run more advance, or the hot humid air may just be too much. There are other resistor values and temps you can use. 72* might be better for you. 90* natuarl IAT's will lower your overall timing even more.

If you start to detonate w/too much timing, your PCM will dump you to a BAD GAS lower timing table for your runs. This is probably what your PCM did after you started to detonate. Add 5+ gallons of gas and it will reset.

Think of it as an adjustable timing ****. Past a certain point you will have more timing than your car can handle unless you can clean up the tune.

<small>[ July 07, 2002, 11:32 PM: Message edited by: MelloYellow ]</small>

NoGo

iTrader: (2)

The KR that I saw during the above test, I believe was from the hot humid air. Later tests, done at night with some cooler air, have shown that the car can take 27+ deg with the timing tricker in.

So, I think that this would be a good mod for, as MellowYellow mentioned, for a car that can take the timing, or when running with better air quality. And yes, the Bad Gas table blows. After a couple hard knock runs, SOTP, you can feel the difference.

My main goal of the test was to see whether or not it would richen up the setup, as some people have been inclining lately. According to my O2's it didn't do crap. However, according to the LTerms, it dropped them roughly 2%.

Exactly, how much KR does it take to kick the PCM over to the bad gas table. From what I've seen, it doesn't take much. And it kills power. I wouldn't be surprised, if a good percentage of this board spend their time driving around on the bad gas table.

<img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />