ECU thread

[resago]

no, you're right. we really should be using an EGT.

[hg2]

in a previous thread, I suggested the use on an RPM switch to activate efies. Also I agree we do need a way to measure the hho and have that be a factor used by efies.

If we are talking standalone ECUs, then we would have to come up with our own maps. we could use our observed LPM and factor that into the values.
we would need to know at what concentration that fuel and timing can be adjusted vs RPM.

I've seen in a few pdfs where the idea of metering hho by use of the tps.Have you seen anything similar to this method?

[scirockett]

monitoring chamber temp and EGT's is important, and metering your HHO into the A/F mixture along with timing controls this. yes we need to monitor this, but if we don't meter it, we have no forumla to fix anything because we don't know what's there..

now, high EGT's should not be an issue at all because we're going for a lean mixture. high EGT's are caused by rich mixtures and/or timing retard that doesn't burn all the mixture and dumps it out the exhaust.

cyl temp is what we're concerned about, and it doesn't take that lean of a mixture to start burning valves, especially under load. These temps are NOT reflected in coolant temp as one might hope.. Coolant temp is regulated by the thermostat and can be perfectly normal while your engine is cooking.. This is why anything but an o2 mod seriously scares me.. but so long as your monitor your spark gap (use COPPER plugs so you can tell..), you can keep an eye on your burn conditions.

off the top of my head:
12/13:1 mixture: a MUST for boost
14.6:1 - stoik, generally the target A/F mixture for N/A under load.
16/17:1 - lean highway cruise mixture.

A 0-5v wideband will produce these number realtime.

EGT's and cyl temps are not generally managed by the ECU. If there's a problem here, there is a problem with the tune.. well, I may be a little behind here, but SA's i've worked with do not monitor this, and I just use analog gauges. thinking outloud, I'm not sure how an ECU would accomodate for this because it's the tune that caused the problem.. bla. need to look into this. My buddy just setup Motec, so I'll hit him out (i can't afford that crap.... : )

oh, back to that chiptuners 10% thing, not sure where that number came from but the ECU's i'm familar with, the chip tuner has 100% full control of the maps and sensor weights.. I know with newer vehicles, you may have 10% control thru the OBD2 port (vag-com for VW's).

[scirockett]

I've seen in a few pdfs where the idea of metering hho by use of the tps.Have you seen anything similar to this method?

Bingo!! now we're talkin..

I'm building a twin charged system and using a DBW (drive by wire) TB for my bypass valve..

For a standard TB with TPS, we could use that 0-5v feedback to determine where the TB is, but control would need to be external.. fail.

for the DBW TB, we can use an I/O that support duty cycle from our standalone ( I have one with Wintec II) to control this..

The next issue becomes, how do we slow down our HHO production.

taking two steps back, we need to deterime what the ideal HHO to A/F mixture is.. hmm.

Love the Meyers concept of production on demand. could it really be as simple as modulating power to the cell?

It makes sense that our target is highway cruising. I seriously doubt current production methods will produce enough to augment WOT pulls, but 99% of the time we're just cruising at 70 or so mph, where our engines are happy with leaner conditions and HHO should be advantagous.. again, an o2 sensor mod with factory management should work perfect here if we 1) understand the effect of HHO, and 2) provide consistent mixtures under these light load conditions.

kick ass.!!

[scirockett]

not sure if I said it, but extreme overleaning will show LOW EGT's.. the heat / mixture never makes it out of the engine.

[hg2]

oh, back to that chiptuners 10% thing, not sure where that number came from but the ECU's i'm familar with, the chip tuner has 100% full control of the maps and sensor weights.. I know with newer vehicles, you may have 10% control thru the OBD2 port (vag-com for VW's).

The 10% is the number that tech support at superchips stated as to how much leaning control the unit is capable of.Did I misunderstand the info that they gave me or can you tell me how much real control these units offer?I'm still in the dark about a lot of this and would very much like to hear your opinion on the use of these tuners and and how much they can accually control mpg gains.

[scirockett]

ah - maybe they mean they'll only lean it out by 10%?
lkasdjklfsd
just looked it up - appears they do their tuning thru the vehicles OBD2 port. It's basically a code reader with the ability to change the tune within factory set values. So there's the 10%.. interesting the factory 'acknowledges' that a 10% leaner mixture is safe.. wonder if this applies to the entire RPM band, or just in closed loop.. hmmm. . anyone?

this is not re-chipping the vehicle, but rather giving you the ability to talk to your vehicles computer. Damn nice to have!!

the chip tuning I was referring to swaps out/modifies the factory chip/tune and replaces it with whatever you want. usually it's to match changes to the motor such as cams, more boost, larger injectors, etc.

for us cheap asses out there, I've used freeware OBD2 software with a cobbed together OBD2 port-serial interface to read codes. plans to build this are all over the internet. otherwise, it's ~$100.

[hg2]

ah - maybe they mean they'll only lean it out by 10%?
lkasdjklfsd
just looked it up - appears they do their tuning thru the vehicles OBD2 port. It's basically a code reader with the ability to change the tune within factory set values. So there's the 10%.. interesting the factory 'acknowledges' that a 10% leaner mixture is safe.. wonder if this applies to the entire RPM band, or just in closed loop.. hmmm. . anyone?

this is not re-chipping the vehicle, but rather giving you the ability to talk to your vehicles computer. Damn nice to have!!

the chip tuning I was referring to swaps out/modifies the factory chip/tune and replaces it with whatever you want. usually it's to match changes to the motor such as cams, more boost, larger injectors, etc.

for us cheap asses out there, I've used freeware OBD2 software with a cobbed together OBD2 port-serial interface to read codes. plans to build this are all over the internet. otherwise, it's ~$100.

Yeah 10-4 on the cheapazzz I'm one of them lol.I asked what kind of mileage improvement I'd get with their mileage miser and the best they could give me was 1-4 mpg increase and for $350,to me wasn't a bargain.

[Jaxom]

Anyone with any tuning experience will tell you that the off-the-shelf chips are basically turds. 9 times out of ten, they just use the factory calibration with minor timing and fueling changes. The 10% number they gave was probably the max. amount that they will deviate from the factory calibration. I have a lot of experience with this from modding my IROC-Z (and yes I tune it myself, in real-time through my laptop.) True tuning allows you full control over the fuel and spark curves, modifiers for things like engine temp and highway mode operation, and even self-diagnostics. It's possible to change DTC parameters so that you can tell the computer how far to let a sensor go before setting a code, or to set the idle speed at 2400rpm if you so desire. The learning curve for this stuff is incredibly steep, and in my epxerience most people who fool around with it only do that: fool around. Very few have the patience and the background to really learn and master engine management. Scirockett, you seem to be on the upper end of this learning curve. What kind of tuning background do you have? Maybe we can learn a few things from each other, and figure some stuff out.

In the grand scheme of things, PCM control will be the most effective way to utilize HHO. Setting up the hardware to put the computer in control of the HHO is simple: just use a pulse-width modulated output from the PCM to drive a solenoid valve between the intake and the HHO generator. This will let the PCM meter HHO flow by controlling how far the valve opens. A simple pressure sensor and PWM controller can then run the generator so that the HHO supply is adequate for demands, but does not build up excessively. The software side of it is the hard part, as code would have to be written from scratch for the PCM to know what to DO with the HHO. Tables and modifiers and calculations would have to be devised and a logarithm written to calculate the HHO valve duty cycle for any given engine condition.....and all that comes after figuring out when and how much HHO needs to be delivered to the engine.

As it stands now, I believe that a proportional delivery of HHO into the engine that varies with load conditions will greatly increase the gains people are seeing. The simple "X lpm all the time" delivery in use now is extremely inefficient. We can all agree that more engine airflow will need more HHO to see equal gains. That means we need more HHO at high RPM that at idle, and more under heavy load than when coasting down a hill. Right now we either have too much at idle, or not enough under load, or both.

I have a duty cycle controller prototype built that will modulate the current supplied to the generator based on a 0-5v input. I intend to use the MAP sensor to power my electrolyzer proportional to engine load, with high hopes of increasing the effectiveness of HHO. If it works, a pulse-counting circuit could be used to proportion the genny current to engine RPM. The next step after that would be a dual-input controller which accounts for both RPM and load. I just need to finish getting the system installed in my truck and we'll see what happens. This is all on a bone-stock Grand Cherokee with 245,000 miles on it, so if it works for me it should work for just about anyone else.

[hg2]

Jaxom thanks for taking the time to write such an informative post.That answered all my questions about stand alone system,tuners and then some.I've only been here less than a week and think I can safely say you must be a huge asset to other members like myself with limited knowledge of ecm and sensor technology.Thanks and I'm looking forward to future posts about the new project you mentioned,and with your experiece I'm sure it'll be successful.