GReddy Emanage or EFI PMS? - Honda Prelude Forum

TimeRacer · 09-09-2004, 03:44 PM

First off I have a Prelude Type-SH with the ATTS system. Don't want to get rid of it thus the reason why I have to get a PMS system. Hondata, Uberdata, etc is out due to this as I have to retain the entirely stock ECU.

Now, I've been reasearching the two units and they each have their own features but seemingly I'm really not sure which to choose. This build will be a very mild build and the internals of the engine will not be upgraded unless they break first but all the bolt ons will be installed. BTW don't tell me to talk to Sharkcohen, I've probably harassed him too much about the topic already.

Thanks Dave!

Here are some highlights for each unit that I can figure out.

Emanage:
* 16x16 fuel table, however it does it by modifying the MAP sensor input thus changing igntion timing tables as well.

* 16x16 ignition map though I'm sure this unit just extrapolates and guesstimates the ignition sequence. The manual states that it has a +/- 1 degree of error.

* Built in VTEC control and VTEC fuel correction factors.

* Built in datalogging or meaning I don't even have to buy more for more software.

- No CEL for VTM wire.

- Can be found used for around $350 w/ ignition/injector and support harnesses.

EFI PMS:
- Has three different fuel/ignition maps you can utilize via a change of a switch. Normally a stock, mild and wild ignition/fuel settings. I probably don't need this as it'll be on pump gas all the time N/A.

* Fuel is controlled by directly changing the pulse width (not confirmed... and I can't tell by the sad instruction manual when it comes down to telling you how they change the fuel / ignition settings) but the PMS does display injector duty cycle.

- Built in O2 sensor readout, but this is more of a novelty than anything as I'm just going to run a stock Honda O2 sensor so it'll be the same show you get from an Air/Fuel gauge or I can just hook up the trusty voltmeter into the wiring harness and do the same thing.

* Changing timing, it directly reads the crank angle sensor. This is not confirmed, can't tell by the dang manual! But is assumed when the unit can read total timing on the fly.

- Some internal barometer and engine temp sensors to compensate for when the engine is cold

- $500 used + needing to buy a OBDIIa harness for an additional $200.

Main Questions: (which I've posted on the EFI PMS yahoo group.. we'll see if I can find some answers)

1. For ignition timing does the PMS actually read the crank angle
sensor and place that in the base map and then allow you to modify the
base map? Or does it just interpolate and guess when the next
sequence should occur? I would only guess that it would do the later
as I don't recall the unit having a learning function.

2. Injector control is done by...? Most other piggyback units modify
the MAP/MAF values by +/- % to those values so the OEM ECU will change
the amount of fuel thus not having direct control over the injector
duty cycle and quite possibly changing the ignition timing in the
process. The manual makes it seem like the PMS has full control over
the injector duty cycle if this is the case how is that done as in
what does the PMS monitor to ensure correct injector firing/duration
sequences? Again coming back to the if or if not the unit receives
and interpets crank angle sensor information.

3. Honda VTEC engagement RPM control... possible without throwing a
CEL code for the VTM wire?

4. Also VTEC related, the fuel/timing maps for the VTEC map can be
done in the NO2 map? Yes? The Honda PMS manual doesn't mention VTEC
at all.

Overall the EFI PMS seems more powerful but considering the amount of work that I'm going to do will the Emanage be powerful enough for me? Plus w/o knowing the answer to the first two questions in particular the EFI PMS, if it changes the settings the same way the Emanage does, isn't any more powerful than the Emanage for a N/A application. It has a few more output displays as in it can show you injector duty cycle, timing, O2 sensor voltage but really all that is telling you what an OBDII scanner would be able to do. But then again, that is only if it modifies the signals similar to an Emanage.

Sooo... which one?

ludehawk · 09-09-2004, 09:28 PM

I'll post up my research in a bit... (hopefully) but I fully researched the e-manage vs. pms a couple of months back, for N/A, I feel the PMS will far exceed anything for the SH

I've got some dynos and other info on my other laptop.

marcucci · 09-10-2004, 05:49 AM

I thought the emanage controlled fuel directly like the PMS by changing the injector pulse width? At least, I thought it required hacking the injector harness which I don't see a reason for otherwise. I have no direct experience with it. My understanding is that both requiring hacking the harnesses so that they can intercept the ECU injector pulse and then deliver whatever pulse you are set up for (wider or narrower).

You can't just hook up a voltmeter to the O2 sensor. At least, unless you have an extremely responsive VU meter it won't do any good on a transient basis, and you can't relate the steady-state output to a given a/f ratio. They are really only good for rich or lean, they are not terribly accurate at the edges off-stoich.

I would suggest getting a harness to hack instead of having to cut up the factory one. LMK if you need one, I can get you one.

TimeRacer · 09-10-2004, 05:54 PM

ludehawk: I wanna see, I wanna see!

Todd:
This is how I got my understanding of the GReddy Emanage in terms of fuel

http://www.mohdparts.com/emanage/man...manual/025.JPG

Seems to me that it modifies it just like a V-AFC and changes the MAP sensor voltage to have the OEM ECU do the fuel correction factor esp with the warning at the bottom. It's far from ideal. Though it does wire in directly to the injector signals shown here

http://www.mohdparts.com/emanage/man...manual/043.JPG

and then again

http://www.mohdparts.com/emanage/ins...elp/index.html

The "#x" are the injector signals according to that, I haven't compared it against my Helms diagram. I can't see why they'd want to tap those signals unless it's only tapping those signals just to see what the injector duty cycle is.... ? But then why would they tap it instead of just monitoring the signals? ugh.

I figured as much for the O2 sensor which is why I figured that I could just hook up a volt meter to it and set it to hold the max/min though I'd only use it for open loop operation as I probably won't mess with anything in closed. I just want to know if I'm just running egregiously rich or lean tuning my settings on the street so when I hit the dyno it'll take less time.

TimeRacer · 09-14-2004, 02:43 AM

Am I the only one who's thinking about this?

marcucci · 09-14-2004, 06:30 AM

Apparently.

I didn't realize they just tapped into it to monitor- in that case, it absolutely cannot vary duty cycle directly, it would need to intercept them like it does the ignition signals. I guess you're right.

You may want to post something about keeping the ATTS with an OBD conversion or EMS. I know a few people have looked into a solution to interface with the ATTS computer. I am not sure what the signals are that are sent back and forth but I would not be surprised if there were a way to accomplish what you need with nothing more than a microcontroller added into the circuit. The e-manage seems to be a band-aid like the VAFC but one that also handles ignition.

What are you really trying to accomplish? What is it that the stock ECU is not doing for you?

ludedawg2001 · 09-14-2004, 01:38 PM

You are not the only one... I am considering this as an option also but I not done any research yet that would be helpful....If I come up with anything I will let you know.

TimeRacer · 09-14-2004, 05:08 PM

I'm just trying to get ignition control and a more direct method of controlling the fuel really. I'm basicaly done with what I want to do for right now (STX limited) in the engine and seemingly the next step would be to really tune what I have instead of just playing with the V-AFC which would lead to an EFI PMS or GReddy Emanage. I don't quite want to move up to a true EMS as I'm not quite to the point to need all that backwards engineering.

LVSBB6 · 09-30-2004, 01:50 PM

Would a EFI PMS OBD2b harness for an Integra work on our cars?

TimeRacer · 09-30-2004, 02:26 PM

No, you need the OBDIIa harness.

LVSBB6 · 09-30-2004, 05:54 PM

Does EFI still supply the harness? I heard they have been discontinued.

Quote:

Originally Posted by TimeRacer

No, you need the OBDIIa harness.

TimeRacer · 09-30-2004, 11:39 PM

You have to find them but seemingly there's plenty of people who still have them. Just by searching around on the boards I've been able to locate three of the OBDIIa harnesses.

LVSBB6 · 09-30-2004, 11:59 PM

Im now in the same boat as you two weeks ago deciding on Greddy Emanage or EFI PMS.

How do you like your unit so far?

TimeRacer · 10-01-2004, 09:53 AM

I don't have the unit as of yet, still in the process of procuring one. Though Sharkcohen has one and Schwett had one, along with 99SS I think? On this board... It seems the units would be much more comparable if it's for a boosted application but for an N/A application the EFI PMS seems to be the much better suited.

sharkcohen · 10-01-2004, 11:13 PM

98SS, and he still has his, too.

I've been keeping an eye on this thread, if you guys have more questions about the PMS put them up here or PM me.

Doug, if you do get one and need any first hand help with it, let me know.

ludedawg2001 · 10-04-2004, 11:14 AM

Can anyone confirm which wire is the VTM wire on the ECU ?

sharkcohen · 10-04-2004, 11:35 AM

Quote:

Originally Posted by ludedawg2001

Can anyone confirm which wire is the VTM wire on the ECU ?

I can when I get home.

sharkcohen · 10-04-2004, 09:40 PM

VTM wire on a 5th gen is C15 blue/black.

TimeRacer · 10-25-2004, 04:42 AM

I finally got the unit and it seems to work, though I haven't really had a chance to play with it. I want to try and wire up the unit w/ VTEC engagement control and using the NO2 table to act as the VTEC table. Since it's not a standalone I can't just delete the OEM ECU out of the loop like this:

I believe at least without throwing a CEL. Does anyone know how to wire the unit up to allow the accessory ground to be able to control the VTEC engagement point?

I also want to try to wire up the unit (as I've been told it can) to use the NO2 table on the EFI PMS to control the VTEC fuel/timing table. To tell the truth I'm not even sure what I need to tap here to activate the VTEC fuel/timing table.

If anyone can help I'd appreciate it!

TimeRacer · 11-09-2004, 10:56 AM

Hrm... Anyone with an electrical background? I am 95% sure that I can just use the relay to control the VTEC solenoid utilizing the switched ground for the EFI PMS accessory port. But my issue is the OEM ECU seeing that there's no connection and throwing a CEL. I've considered two methods around this, can anyone tell me if either of them will work?

One is hooking the ECU side of the VTEC solenoid wire to the VTM wire as they're both based on low RPM low voltage, high RPM battery voltage... I think I would need to tie this into a ground and throw in a resistor but I'm really not 100% sure. The resistance should be around 15-30 ohms according to the Helm's for the VTEC solenoid.

The other is hooking the VTEC solenoid wire straight to ground with a resistor and diode inline. Again I'm really not sure what kind of diode I would want in this setup.

If any of you can tell, electrical isn't my strong point and I want to be sure of this so I don't fry my ECU. Someone's had to of thought about making a homebrew VTEC controller before!