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I have no idea whether the PMS or the Uni-Chip would work. I never got to take a good look at the PMS system. Someone had one on their OBDI Prelude locally, but they just got rid of it. I don't even know if it works on OBDII Preludes. You would have to make sure that the ECU does not trigger a MIL, which would be difficult playing with all it's inputs/outputs like that.

I haven't dyno tuned the E6K, yet. I will as soon as my engine is back together again. When we took the engine apart last time I found I was running it very rich. I'll spend an hour on the dyno and tune it with a wideband at part throttle properly. Then do some real tuning when it's properly broken in.
 

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my hope is that the pms does not modify any of the inputs on the ecu, and rather only modifies the timing and injector signals directly. i think this would not throw any codes, as timing devices like the j&s or jr btc do not seem to.

DirtyLude said:
I have no idea whether the PMS or the Uni-Chip would work. I never got to take a good look at the PMS system. Someone had one on their OBDI Prelude locally, but they just got rid of it. I don't even know if it works on OBDII Preludes. You would have to make sure that the ECU does not trigger a MIL, which would be difficult playing with all it's inputs/outputs like that.

I haven't dyno tuned the E6K, yet. I will as soon as my engine is back together again. When we took the engine apart last time I found I was running it very rich. I'll spend an hour on the dyno and tune it with a wideband at part throttle properly. Then do some real tuning when it's properly broken in.
 

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My only issue is that if it modifies the injector duty cycle after the ECU, the ECU might not like what it's reading from the O2 sensor during part throttle.

There's a chance it may work. I don't want to be the one to test it, but it might have a chance. I wonder if there's anyone who would loan out the OBDII PMS for a test?
 

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DirtyLude said:
My only issue is that if it modifies the injector duty cycle after the ECU, the ECU might not like what it's reading from the O2 sensor during part throttle.
How so? Wouldn't you be able to tune the car to a decent mixture during part-throttle?

Based on the PMS site, there are 4 different throttle settings (idle, low, med, WOT) with different fuel and timing maps.

My only issue is wondering how everything is done after the ECU: are the maps newly written from scratch, or are the made 'relative' to ECU settings. Thus, if the ECU sees a richer mixture, and starts leaning out, you'd have to richen it back up with the PMS. Either that or the NTPOG OBDII Bypass...

C'mon schwett, be the guinea pig already! :D
 

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iranman said:


How so? Wouldn't you be able to tune the car to a decent mixture during part-throttle?

Based on the PMS site, there are 4 different throttle settings (idle, low, med, WOT) with different fuel and timing maps.

My only issue is wondering how everything is done after the ECU: are the maps newly written from scratch, or are the made 'relative' to ECU settings. Thus, if the ECU sees a richer mixture, and starts leaning out, you'd have to richen it back up with the PMS. Either that or the NTPOG OBDII Bypass...

C'mon schwett, be the guinea pig already! :D
after reading the sites faq about the system (let me qoute some real quik..
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Q1. At idle or part throttle the 02 voltage varies; why is this happening?
A1. This is a result of the system operating in the closed loop mode. The ECU is trying to maintain a 14.7:1 air/fuel ratio. It adjusts the mixture 30 times a second, and what you are are seeing is the result of this mixture change as reflected in the 0 2 voltage readings.

Q2. If I add fuel during idle or part throttle it just seems to relearn it; why?
A2. This again is closed loop in operation. The stock computer has a window of about ±20% fuel that it can adjust in. Any adjustment you make that falls within this window will be
changed by the stock computer in an effort to maintain the 14.7:1 ratio. Adjustments made here should be in an attempt to cause the computer to go closed loop for optimum fuel mileage and emissions.

Q.3 Will it relearn at WOT too?
A3. No. Any adjustments made at high load or WOT will be added to the total. This is what’s known as open loop. You will notice the 02 voltage fluctuates more slowly under these conditions.
------------------------------------------------------------------------

well it seems to me this thing is a glorified apexi safc. just by the answers they give you can see that this unit has no ability to operate in closed loop mode without the ecu changing the modifications since it has no control over the o2 sensors return values. now if it had some kind of application base maps with the ability to control what the ecu sees from the 02 sensors then you would be in the game. seems its only benefits are in the open loop range when the ecu doesnt give a **** what the o2 sensor says therefore the pms will be able to adjust because the ecu doesnt care what the consequences are since it isnt reading the 02 sensor anyway. christ you can even see from the explanation in one question 2 they say all mods to the signals at idle and part throttle should be kept within the ecu's +20% range anyway for emissions purposes. B.S!!! its cause its signal alteration will be learned and altered by the ecu to what it thinks should be there. if this were to truley work it would need to be able to manipulate the signal the ecu see's from the o2 sensor so the actual fuel modifications could masked behind a false signal and the ecu would see no reason to alter anything. only probelm with creating the false o2 signal is you would be running blind when trying to figure out if your lean or rich unless you had the option of reading the o2 sensors voltage before it was altered although i have no clue how the hell you would do it. the other thing i hate about these piggybacks is that everything is linear. if only things in the real world worked that way. seems like this would work better for the supercharger guys then the turbo guys. only rpobelm i would see is if a belt slips and catches that boost spike night leave you ****ed.

welp back to hittin the bottle......

p.s. sina i took your word and signed up, seems like a good choice and some informative people to go along with it
 

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ILikeNakedGirls said:

well it seems to me this thing is a glorified apexi safc.
I beg to differ. From what I've gathered, the PMS (in it's "piggyback" mode) functions not like the piggybacks you mentioned (where the incoming signals to the ecu are altered), but rather alters the outgoing signals to the related engine components (i.e. distributor, injectors, VTEC solenoid, etc). Like the piggybacks, however, everything is done in relation to the normal ECU outputs: i.e. +2% here, -10% over there, etc.

The "standalone" mode ignores whatever the ECU outputs and instead functions off of the EEPROM inside the PMS unit itself (which is updated via laptop). The ECU is still kept to power 'other' accesories.

Source: http://www.newwave.net/~flanham/wlanham/
It may be for an RX-7, but it deals with general PMS functions.

ILikeNakedGirls said:


p.s. sina i took your word and signed up, seems like a good choice and some informative people to go along with it
Welcome aboard, you old geezer. :D :wave:
 

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The injector pulse widths are modified after the ECU by the PMS and the PMS has it's own injector driver. I at least know that about the thing, since I was reading about someone who bought a used one off a guy who tried running low impedence injectors without a resistor box and burned out the PMS. So it still has the same limitations as the stock ECU with injectors, it will need the resistor box to run low impedence.

I know people are running them succesfuly, but I've never heard of anyone being truely happy with them. If it's the only option for keeping the ATTS with standalone type features, then there's not much choice.
 

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iranman said:


I beg to differ. From what I've gathered, the PMS (in it's "piggyback" mode) functions not like the piggybacks you mentioned (where the incoming signals to the ecu are altered), but rather alters the outgoing signals to the related engine components (i.e. distributor, injectors, VTEC solenoid, etc). Like the piggybacks, however, everything is done in relation to the normal ECU outputs: i.e. +2% here, -10% over there, etc.

The "standalone" mode ignores whatever the ECU outputs and instead functions off of the EEPROM inside the PMS unit itself (which is updated via laptop). The ECU is still kept to power 'other' accesories.

Source: http://www.newwave.net/~flanham/wlanham/
It may be for an RX-7, but it deals with general PMS functions.



Welcome aboard, you old geezer. :D :wave:

after reading some of that site i see what your saying. you know its always great when the actual company that makes the **** gives bairly any info about the thing (at least from what i found on thier site). and vague info leads to false assumptions on my part << taking the misinformed assholes bow>>. anyways, i think im gonna call them and see if they have a more detailed book i can get ahold of. one thing though, it can obviously switch from piggyback to stand alone mode at a given input but are both modes included for that 800 something price or do you have to purchase the software for the laptop programming as a seperate item? all in all it seems like a nice way to keep your other functions alive but it seems like a real muther****er to get perfected but thats why most dyno places have package deals because they know idiots like us are trying not to blow up our cars. welp time to pack for the drive to pittsburgh.
 

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The $800 price is just for the unit itself, which comes with a crazy old-skool controller that modifies fuel + ignition maps in increments of 2000rpm. :nono:

The $300 software brings the increments down to about 160RPMS, plus gives you that standalone feature.

Most standalone's are especially noted for being like a walk in the park.

WTF? You're going back to Pittsburg already?!?
 

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iranman said:
The $800 price is just for the unit itself, which comes with a crazy old-skool controller that modifies fuel + ignition maps in increments of 2000rpm. :nono:


sounds like to much fuzzy linear computer math to me. i think i would still be using more deodorant then normal if i knew this was whats holding my high compression boosted motor with small injectors together on a daily basis although it is better then nothing. :rolleyes:

iranman said:
The $300 software brings the increments down to about 160RPMS, plus gives you that standalone feature.
deffinatly worth the extra drugs you would have to sell or old women you would have to mug to get it from my standpoint!! :bigthumb:

iranman said:
Most standalone's are especially noted for being like a walk in the park.
synical bastard :malken:

iranman said:
WTF? You're going back to Pittsburg already?!?
hey man im home sick, remember your not the one that has to live in ocala!!!!! besides i need laid pretty bad and i dont have any skanks down here i can call on but i still have some cards to redeem up north :bigthumb: besides i get to stop at nopi on the way back down and blow my money on useless **** for my car that will decrease its value and make everyone want to race me going 120 across a bridge in tampa that ive never driven before during heavy traffic :malken: i'll be back on new years eve but im heading to orlando to meet up with a purehonda buddy to get sauced.
 
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