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Adjustable FPR and Dyno.

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Old Oct 20, 2001 | 06:44 PM
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Default Adjustable FPR and Dyno.

My first dyno session several months ago prompted me to increase the fp to within stock value, as I had adjusted it below stock. Power was much better.

Today's dyno session prompted me to decrease the fp to lower stock range, as I had adjusted it after the last dyno session to a higher setting. Again, power was much better.

I pulled the plugs yesterday and they did look a little dark, of the brown color, so the last change might lighten up the plug color over time to tan or gray.

I think this means as long as power is ok, it is best to stick with the stock fpr.
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Old Oct 20, 2001 | 06:56 PM
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Hey prolene, this is June, the asian guy you met with the glasses and hat today at the Dyno session.

It was cool that I got to see a couple S2000s dyno today, never actually heard the vtec that clearly before. But anyways, it was good meeting you. Also, I love that spoon intake and spoon 1 piece exhaust you have, now all you need is the spoon motor, hah. hope to see you again sometime.
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Old Oct 20, 2001 | 07:01 PM
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Thanks for coming out, Guys. I think we`ll be throwing one once a month after SEMA

Ryan
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Old Oct 22, 2001 | 11:04 AM
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Are you sure the ECU isn't adjusting out your fpr adjustments?? I think the ecu might be re-learning. You might check this thread to see what UL said about your car.

https://www.s2ki.com/forums/showthread.php?...2804#post342804

When are we going to do another roll-on comparison
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Old Oct 23, 2001 | 10:46 AM
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Originally posted by MarkS2K
Are you sure the ECU isn't adjusting out your fpr adjustments?? I think the ecu might be re-learning. You might check this thread to see what UL said about your car.

https://www.s2ki.com/forums/showthread.php?...2804#post342804

When are we going to do another roll-on comparison
hmm, that's interesting...but wouldn't it take a little bit for the ECU to re-learn what's going on?

I know that on my car, whenever I raise the boost, it takes about 1 hour or 1 1/2 hours for the ECU to realize that it's over boosting and will limit the throttle or cut fuel.
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Old Oct 23, 2001 | 11:03 AM
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What I'm saying is that Prolene changes his settings on the fpr to get more power, but then has to change it the next time he dynos. I think what's happening is that he gets more power initially, but then the ecu learns the adjustment and compensates for it. He then changes the fpr again to get the gain, but the ecu eventually compensates for that. So, you can adjust from dyno session to dyno session, but the ecu might be compensating your adjustements out.

Originally posted by integrate


hmm, that's interesting...but wouldn't it take a little bit for the ECU to re-learn what's going on?

I know that on my car, whenever I raise the boost, it takes about 1 hour or 1 1/2 hours for the ECU to realize that it's over boosting and will limit the throttle or cut fuel.
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Old Oct 23, 2001 | 03:05 PM
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The ECU isn't supposed to tune-out WOT response. WOT is claimed to be "open loop", working from fixed maps.
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Old Oct 23, 2001 | 04:48 PM
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Hey Integrate, it was nice meeting you! Hope to see you again soon.

Mark, if what you say is true, the car wants to run at less than optimum setting at wot, and is decreasing power whenever it sees too much power. My guess is that there is an optimum setting for fpr that translates to optimum wot setting. So far, around 47 mm Hg, the low of the stock setting range, gave me immediate power increase each time. I suppose dyno at this setting next time would show what is going on.

I think if at closed loop, if not much _tuning_ needs to be done by the ecu, that might translate to leaving things as they are at wot. If rich at closed loop, then lean at open loop wot over time, and vice versa. However.......

Penforhire, I think what Ultimate Lurker states is correct: "Long term fuel trim is computed from short term fuel trim and indicates changes occuring in the fuel supply system over a long period of time." And "Common sense dictates that any long term changes in fuel trim (i.e. Long Term Fuel Trim numbers) must be applied both in open and closed loop modes." So my immediate results may change over time to a less tuned state, perhaps more rich and too much so no matter what was the closed loop state. VAF-C may be the reasonable alternative or Mugen/Spoon ecu.
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Old Oct 23, 2001 | 08:27 PM
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Hey Doc, 47 mm Hg? what are you measuring, blood pressure?
That's less than 1 psi

You must be talking 47 psi, yes?
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Old Oct 23, 2001 | 08:35 PM
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[QUOTE]Originally posted by RT
[B]Hey Doc, 47 mm Hg?
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