TOM'S Fuel Map Controller
https://www.clublexus.com/forums/per...mp-on-2is.html
(and the product discussed in this thread is _not_ a self-tuning model that constantly adjusts itself based on WBO2 feedback like his)
No human on earth can "feel" a 5 hp gain on a 200+ hp car.
As I said, AFCs have been run on 350s (Jeremy used one I believe) and gains were barely above that (~7 hp on a 350, so should be less on a 250)... and of course the computer tunes the gains back out after 50 miles or so, he only used it for the track.
In theory you COULD do the following-
Hook up datalogging equipment to monitor the car
Hook up an AFC
Lean the car out to gain your 3-5 hp on a 250.
Now, the ECU will notice "Huh, I'm running leaner than I should, better add more fuel" and you'll lose that 3-5 hp after maybe an hour of driving.
Then you can lean it further with the AFC
Now, the ECU will again notice "Huh, I'm running leaner than I should, better add more fuel" and you'll lose that 3-5 hp after maybe an hour of driving.
Then you can lean it further with the AFC
And so on, and so on... eventually you will exceed the capacity of the ECU to add any more fuel to the system, and your 3-5 hp gain will stay.
That's the good news.
The bad news is if you ever -actually- run any more lean than just your AFC adjustment for any reason (and there's many reasons that can happen) you will damage your engine because the ECU is no longer capable of enrichment of the fuel mixture to protect the motor.
That seem worth 3-5 hp to you?
(And well before that you might well trigger a CEL because the ECU thinks "There must be something wrong if I'm having to dump THIS much extra fuel ALL the time" and have that to deal with as well)
"Feeling" again i think makes a diff, cause even though its psychological, reality at the end of the day is wat u perceive it to be, not wat it actually is. The power of the mind with regards to tuning the IS is ur friend. I know my exhaust only adds max 4hp, but hell it "feels" faster. Thats good enough for me. Even if feeling in this case is hearing.
Same goes for turning the power button on. I KNOW im not getting any bhp, but it "feels" faster. This pyschological performance gains imo are worth it. Im not gonna track my car, but for spirited driving as long as it puts a smile on my face im happy. Heck i know i can prob put the same smile on my face with none of these mods, but like i said ur imagination is a powerful thing.
Back to the fuel map controller
How bout this: I dont plan on running it lean ALL the time, quite the opposite, Id run it nuetral or rich and just when I wanna run in lean every once in a while for short periods (say 20mins), then ill put it back to stock configuration.
I just want it there when i need it.
so it will go like this
from the pic i can see around 11 diff settings on the afc, lets call the no.1 the richest setting, no. 6 the stock setting (since its red while the others are white i can assume this is ur car in its neurtral state) and no.10 the leanest.
Most of the time Id run the afc at 6. On those rare long distance journeys on innercity roads id run it at lets say 2 or 3(to take advantage of fuel savings). Most of the time my long journeys will only last an hour or so anyway, and if by the time i reach my destination the car's ecu re-adjusts the richness to normal i wont care anyway (well I guess this depends on how the ECU re-adjusts)
Since the ecu reset itself, and im still at 2(rich) then id slowly adjust it one notch up per day allowing the ecu to recalibrate itself, back up to 6 (neutral) and then Id leave it there for everday driving
for spirited driving, lets say once every couple of days id bump the afc to 8,9 or even 10, 11 depending on the circumstance. ID leave it on 10 for that drive (20 mins or so) enjoy it, and then adjust it back down to 6, bringing the a/f backa to its neutral state before the ecu has time to adjust.
Thats how id use it and thats how i think it could (possibly???) work.
one more question: if i run it rich (or lean) while the car is on, then turn the car off and afterwards adjust it to 6, when i turn the car on a few hours later will it automatiaclly adjust to the 6th setting(Assuming the ecu hasnt recalibrated itself) ? or will my most rich (or lean) setting now b set at 6?
Im trying to figure out how this thing actually works
lemme know wat u think?
back to the percieved vs. actual real world resut discussion:
Like i said earlier ur imagniation is a powerful tool, if lets say theoretiaclly the ecu didnt readjust itself and it were possible to keep it at 10(leanest setting) and maintain that 3-5hp diff all the time, ur brain will adapt to this and this setting will become normal feeling (in ur perceived world), then this device is actually less useful
Even in the perfect work scenario Id k eep it at 5 and use it at 10 only when i wanna feel that extra bump for those short bursts of spirited aggressive driving.
Last edited by ndk83; Jul 30, 2009 at 06:13 AM.
By that I mean if I sat you in two IS250s, one with 204 hp, one with 207 hp, you'd be unable to reliably tell which was which so long as that 3hp came from something that didn't change the sound of the car (like intake or exhaust)
If you just want to "feel" like you're doing something put in a $5 **** that's not attached to anything...the _actual_ felt difference will be about identical and you'll save time, money, and risk to your engine.
As to your question on the car remembering, I haven't done datalogging on the 2IS specifically, but what I've seen in the past, and I'm simplifying a bit, is that a car will have both long term and short term fuel trims.
The long term are the over lots of days or miles, the general trend of adjustment it makes to its base fuel maps... the short term trims are what it's doing pretty much right now. Long term trims don't reset to neutral when you turn the car off.
By that I mean if I sat you in two IS250s, one with 204 hp, one with 207 hp, you'd be unable to reliably tell which was which so long as that 3hp came from something that didn't change the sound of the car (like intake or exhaust)
If you just want to "feel" like you're doing something put in a $5 **** that's not attached to anything...the _actual_ felt difference will be about identical and you'll save time, money, and risk to your engine.
As to your question on the car remembering, I haven't done datalogging on the 2IS specifically, but what I've seen in the past, and I'm simplifying a bit, is that a car will have both long term and short term fuel trims.
The long term are the over lots of days or miles, the general trend of adjustment it makes to its base fuel maps... the short term trims are what it's doing pretty much right now. Long term trims don't reset to neutral when you turn the car off.
for any hp gain is great especially if you combine it with other mods....
who knows stock might give you 4-5 hp but add a exhaust and a intake and headers and might end up givving you ten more plus the other hp from the other parts
i know ill take it... if this works for the F i'll get it and see if there are any gains... veryy interesting thread
alf
Something like this should always be tuned on a dyno or wideband to be safe, I would never adjust anything without knowing what'll happen or have any way(s) to monitor what it does. Also resetting the car is easy to do, just make sure u redo all ur windows so they work
. Also, turning the dial up/down without anyways of monitoring the AFR is a no no in my book.My .02
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Each time i plug it in, it logs a code and the check VSC flashes on the dash..
Hope to hear back soon.!







i want boost

