Heresy - Interceptors and HHO

[casagoya]

Since my ultimate objective is maximum economy, not necessarily performance, I will be adding HHO after finishing the mechanical mods.

So far so good, now for the heresy ...

Is there a good reason to use Tunerpro and reprogram the delco or can I expect an easier time using a haltech interceptor?
Second hand interceptors on ebay are about $400 so the cost difference will not be so great

Tom

[antus]

the thing with hho (i have had some discussions with my mate who is trying this stuff) is that you cant actually meter or regulate the amount of gas coming out the hho cell. Also, it is gas with hydrogen an oxygen in it how much of it should be considered fuel and how much oxygen (not that it really matters until you can meter it anyway). Then what ecu, if any can deal with such a substance? What differences do temperature make to it in gas form, and how do you compensate for that?

The 'interceptor' if you mean the hacks that sit in front of sensors (i re-read your post, you say haltech interceptor so you dont mean the dodgy hacks) are not good as they are not accurate, can not be programmed, for different scale between the low and high ends of the scale or the operating environment (temp, gas flow) and so are very hit and miss.. more miss than hit really. (i'll leave that in as I know people do try the dodgy ones and thats something for them to think about). As far as i can understand it so far, I think it would be impossible to get implementation and mixtures right without gas metering, and special software that can map temperature vs gas flow affecting both air and fuel. Also i'd be interested to know how much extra power you would make (you would need more power from less to need less fuel to get the extra economy) and if that would be more than the extra magnetic resistance on the alternator collecting the power for the hho cell.

I would also be very interested to know in real terms the amount of gas from the cell, because when i think of the amount of air passing through a typical intake pipe under load it seems like a lot of air, and when i think of the cell, its got some bubbles coming off it... i cant see that you'd be talking more than 1% at absolute max of hho vs air going in to the engine. Is that enough to make a difference or is there better information available about this?

[casagoya]

With HHO the idea is to make more of the normal fuel burn in the cylinder rather than go out the exhaust.
The HHO is not actually treated as fuel.

The main side effect is that the exhaust is cleaner with much higher O2 content which screws up closed loop cruising.
Ideally you want to run with AFRs greater than 14.7 and this is where I want to be able to retune.

After that I will work on leaning out the fuel and ignition maps.

The cells I have in mind generate 2-5 litres/min at 15-25 amps 12V.

If you really want to get heretical, then check out the Volo Performance site and see what they do for OBD-II vehicles.

[antus]

hmm well in that case its not just closed loop. you'll need to disable the BLM learn functionality as that wont work either. If your o2 sensor circuit throws an error you might need to mask that error. Possibly you'd need to visit the temp correction tables, but depending on the amount of hho it might not be a factor.

[vn5000]

My neighbour had one of those hydrogen oxygen conversions fitted to his nissan x trail for $1000 .They claimed fuel savings up to 50%.He drove it for a month and took it back for a refund as he said it made no difference to fuel economy at all.

[casagoya]

HHO is stil experimental and the oft repeated message is that without retuning the ECU the potential gains are often not realised. Have also heard reports of worse comsumption. The theory is still something I want to explore after some basic mechanical mods (CAI, exhaust, Gadgetman).

Will report progress here if I get time before I have to sell the car on move OS.

[AntBoy1979]

Getting worse economy is true. the hho mix helps the fuel mixture burn better and if the ecu is not reprogrammed, the ego believes the engine is running lean due to less or no unburnt fuel in the exhaust and bumps up the amount of fuel getting pumped in.

[vn5000]

To get scientific ,Newtons law states that you cannot create or destroy energy.
The energy required to split H2O into hydrogen and oxygen is the same as the energy released when oxy and hyd burn and turn back to water .Unless you can use solar cells to create the hydrogen and then store it i cant see any benefit.This is how the new Honda hybrids will work .You have solar cells at home that create hydrogen which is then stored for you to fill your car.The only other way is to harness the energy wasted when braking.

[AntBoy1979]

You cannot "create" energy, this is true. You also cannot get out more energy than what you put in.
The hydrogen oxygen mix you get from electrolysis, if combusted alone does not produce as much power as it took to generate.
But using it as an additive, it causes the petrol to burn more effectively and completely, so you can dial back the amount of fuel getting squirted in and get the same or better power and better economy with the added "green" benefit of reducing or eliminating unburnt fuel from the exhaust, no need for that catalytic converter anymore! You need to slightly retard the timing as the fuel mixture will now ignite quicker and burn faster. Another problem is the exhaust sensor, with cleaner exhaust gasses the sensor will tell the ECM/PCM that the engine is running lean and will start squirting in extra fuel untill unburt fuel starts coming out the exhaust again past the exhaust sensor and getting mostly burnt up in the catalytic converter, just like what was happening before you started using HHO! Only this time around your burning more fuel to get the same exhaust reading. This is why some people report getting worse mileage using hydrogen, they neglect to change the AF ratios! If you have a NA engine with a basic points dizzy you've got it easy, the only thing you need to adjust is the fuel mixture needle on the carby and give the dizzy a twist!

[Holden202T]

if you have a delco its not much harder to adjust it