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homersimpson30
08-02-2008, 10:10 AM
A coworker told me that hho might cause pre igniton cuz its so flamable, and cause engine damage? Possible??

donsimpson12
08-02-2008, 10:52 AM
A coworker told me that hho might cause pre igniton cuz its so flamable, and cause engine damage? Possible??

Timing should be a concern if your pumping a lot of HHO in... It does explode faster than fuel. That's why timing on engines are before TDC (Top Dead Center).... On a carburetored engine with a lot of HHO, it would be easy to retard the timing a bit.. On a computer car, you'll need to control the computer. Firing too soon will explode the HHO and then your piston is fighting the thrust of the HHO explosion which will surely effect the efficiency.

I've been dinking around with a prototype system, but I really think I need to set this thing up on an old school engine for optimal performance tweaks and ease..

wlf89
08-03-2008, 08:22 AM
could just do like i do put a switch inside the cab to turn it on or off and about a minute before you turn the engine off turn the hho off and let it all burn out of the engine then you will know for sure it aint going to hurt the engine when you start it

donsimpson12
08-03-2008, 08:43 AM
could just do like i do put a switch inside the cab to turn it on or off and about a minute before you turn the engine off turn the hho off and let it all burn out of the engine then you will know for sure it aint going to hurt the engine when you start it

That only clears out the HHO and removes any moisture from the exhaust and engine... Imagine pre-detonation as spark knock.. you'll get it under load.. and it burns the top of the piston and valves..

;-)

homersimpson30
08-03-2008, 04:55 PM
so is this theory possible. can it some how ignite in the cylinder when its not suppose to?

EltonBrandd
08-03-2008, 06:15 PM
so is this theory possible. can it some how ignite in the cylinder when its not suppose to?

The gas will only ignite with a spark, especially as diluted as it is by the time it reaches the combustion chamber. And if it did knock most engines will retard the timing to rectify the knock. My car doesn't utilize knock sensors and I have never had a problem so far. If I use regular 87 octane fuel at sea level my car pings, I have to run 91 octane to prevent that. I'm going to switch back to 87 to see if the hho will help burn all the fuel at once to see if eliminates the pinging. As far as pre-detonation goes I would only be worried about that if I was running my timing way to advanced.

scirockett
08-06-2008, 11:50 AM
pre-ignition and detonation (pings) are two completely different conditions.

pre-ignition is a severe condition where the af mixture is ignited BEFORE the spark. This will kill a motor FAST. This is typically caused by excessively low octane (ignition upon compression) or a hot spot that causes burn before the spark (metal debris in the chamber, carbon build up, wrong spark plugs..). This condition would exist with or without HHO.

detonation or pinging is an anomolie that occurs when the mixure is ignited by the spark plug, but is not a clean burn, rather could be multple burns, and causes the piston to rattle which is the noise you hear. Engines can withstand detonation to a certain degree, however severe detonation under load and high boost can blow up pistons quickly. Causes of detonation are low octane/ high compression, too much timing advance (especially under boost which also increases compression), or a lean mixture (plus others i'm not thinking of now).

Watching people lean out their mixtures without knowning or metering the correct amount of HHO to compensate for this lean condition, I would expect to see some detonation. :) Hell, with a lean mixture, maybe the LACK of detonation is proof (well, partial proof) that HHO is helping the burn!!

Also, there are many variables when HHO is mixed with gasoline, but when HHO is the only source of fuel, reports have shown ignition timing needs to be retarded to TDC because of how freekin fast HHO burns.

I'm still trying to figure out two things:
1) how HHO effects octane rating of the fuel
2) how HHO effects the AF mixture.

I have seen references where universities have done studies that show HHO helps lean conditions, but the reports didn't have any data. If anyone has seen any info on how HHO effects either octane or mixture, i would LOVE to see it!!!

donsimpson12
08-15-2008, 12:48 PM
SciRockett... Very good info and I agee with all you said.. ;-) Not that it matters.. lol... but...

I also have read conflicting stories about HHO helping lean conditions, ect..

Some of what I've read simply doesn't make any sense..

Helping out lean conditions, agree, but with engine tunings that are conducive for both fuel and HHO...

I also don't get the threads about HHO raising the Octane levels..
High Octane fuels (racing fuels) do a couple of things..
Reduces spark knock (Timing / High compression)
Lower flash point and burn speed. (Which is why higher performance engines require racing fuels)

Without getting all sideways over fuel octanes and burns, I'm saying that HHO has an increased flash point and burn speed. Much faster the fuel. (Thus the need to retard the ignition timing) So I'm a little lost when I read that HHO raises the overall octane level.. ???

Marlon
07-21-2009, 03:15 AM
The octane rating of gasoline tells you how much the fuel can be compressed before it spontaneously ignites. When gas ignites by compression rather than because of the spark from the spark plug, it causes knocking in the engine. Knocking can damage an engine, so it is not something you want to have happening. Lower-octane gas (like "regular" 87-octane gasoline) can handle the least amount of compression before igniting.
*Hydrogen does not fit well into the normal definitions of octane number. It has a very high Research Octane Number (RON) and a low Motor Octane Number (MON) so that it has low knock resistance in practice, due to its low ignition energy (primarily due to its low dissociation energy) and extremely high flame speed. Basically this means that hydrogen will ignite easier and have a lower octane rating at higher rpms and higher compression ratios.

That being said, hydrogen has been reported to have an octane rating of 130, and the fact that some people claim that hho made their knock go away would seem to support this.

However... HHO is 2 parts hydrogen and one part oxygen, so the octane rating and how your engine reacts, one would likely have to take into account the oxygen content as well.

Also one must keep in mind than not all HHO generators produce HHO of the same proportions. As the atoms are separated by the electrolysis. Hydrogen bubbles begin to collect on the (- Anode) plates, and Oxygen collects on the (+ Cathode) plates. So 1/3 of the gas produced is Oxygen, and the other 2/3 is Hydrogen.

Octane aside HHO does make the gas burn more quickly so the more HHO you add in the more you will need to retard the timing.

what I would like to say in summary is: when injecting HHO, less is more.

vegasmax
07-30-2009, 01:10 PM
Being aware or a excessive lean condition is very important. A lean condition will cause things to melt. Racers would check their spark plugs to read the condition of their fuel mixture and timming...as it has a direst result on the plugs and leaves sign of how well the engine is burning fuel.

You can find a complete set of pictures and it will explain each condition and causes on the web. worth reading.

HHo is a higher octain fuel and burns fast...that what if you want to run on stright HHo you must set the spark AFTER TDC not before. With racing fuels you are able to run more timming in most cases however it depends on the Altitude and other factores as well such as compression and flame travel. Ping is pre-ingetion of the fuel cause from low octain and or hot spots in the combustion chamber.

just to touch on it here. read more on the web...but beware of a too lean condition...hopefull you'll destore your spark plugs before any other damage is done.

PeteVamped
07-31-2009, 05:23 PM
You may want to buy a guide first which will tell you step by step by step how to build your first one. After your first one and complete set up is finished it only gets easier from there. Then you can start to experiment with other ways. Some of the guides on the market today show you the dos and donts and how to avoide engine damage. I would try that first and go from there.

Q-Hack!
08-01-2009, 10:26 PM
HHo is a higher octain fuel and burns fast....

Actually you have it backwards... HHO is a lower octane fuel.

The octane rating of gasoline tells you how much the fuel can be compressed before it spontaneously ignites. When gasoline ignites by compression rather than because of the spark from the spark plug, it causes knocking in the engine. Lower-octane gas (like "regular" 87-octane gasoline) can handle the least amount of compression before igniting. HHO ignites at a lower pressure than gasoline, so therefore it has a lower octane rating.

Racers use high octane fuel because they are running a much higher compression than your average grocery getter. Anybody who believes that higher octane gives you more power, has bought into the gas companies hype. Octane adds nothing to the power of an engine. It only keeps the fuel from self igniting.

However your comment on being careful with leaning out your engine is spot on. I highly recommend people get an EGT. They are a bit pricey but well worth the safety to your engine.

Roland Jacques
08-02-2009, 10:49 AM
Complicated subject IMO.

quote http://www.hydrogenassociation.org/general/faqs.asp#octane

What is the octane rating of hydrogen?
Short answer: "130+" according to a study done by the College of the Desert and Sunline Transit Agency

Longer answer: The octane rating of gasoline tells you how much the fuel can be compressed before it spontaneously ignites. When gas ignites by compression rather than because of the spark from the spark plug, it causes "knocking" in the engine. Knocking can damage an engine, so it is not something you want to have happening. Lower-octane gas (like "regular" 87-octane gasoline) can handle the least amount of compression before igniting compared to higher octane grades (like "super" 93-octane gasoline).

The compression ratio of your engine determines the octane rating of the gas you must use in the car. One way to increase the horsepower of an engine of a given displacement is to increase its compression ratio. So a "high-performance engine" has a higher compression ratio and requires higher-octane fuel. The advantage of a high compression ratio is that it gives your engine a higher horsepower rating for a given engine weight -- that is what makes the engine "high performance." The disadvantage is that for gasoline, it costs more.

Hydrogen has an octane rating of 130 because it can be compressed more than gasoline and 100% octane before the fuel automatically ignites in the engine. (Gasoline with 87-octane has 87% octane, a special kind of hydrocarbon that makes up gasoline and other fuels).

Here are some other octane ratings:
Methane: 125

Propane: 105

Octane: 100

Gasoline: 87

Diesel: 30

Q-Hack!
08-02-2009, 12:52 PM
While hydrogen, by itself does have an octane rating of 130+, please remember that we are talking about HHO. Hydrogen by itself is not stoichiometric; HHO is.

Also, your little chart is misleading. While you can compress Hydrogen, Methane and Propane (they are gasses) you can't compress Gasoline until you vaporize it. Which coincidentally is what happens when you make it stoichiometric in a carburettor or fuel ejection. The values of 87 for gasoline and 30 for diesel are at stoichiometric and the rest of the list is not.


FYI, the new Ford P2000 runs at a fuel to air ratio less than stoichiometric in order to increase the octane rating. Hydrogen will become stoichiometric at 34.2:1 in normal atmosphere. Ford is using a ratio of 86:1

BMW's 750hL is using a different method. They cool the hydrogen down to a chilly -423 F. This has the added benefit of reducing the space required to store hydrogen. But primarily its so that they can run at 10.5:1 compression.

All of this is academically moot anyway. The HHO we are adding to the engine is so diluted by the time it hits the cylinder, you are nowhere near stoichiometric.

cabrera
08-02-2009, 02:12 PM
but I really think I need to set this thing up on an old school engine for optimal performance tweaks and ease..

My thought exactly but only to learn 1st. The newer cars with all their sensors would require more electronics to tweak them. With a basic motor, you can test your build before you have to add MAF enhancers & 02 extenders etc.

This is my initial "test car" Basic & Simple!

http://home.comcast.net/~cabrera1/DSCF0688a.jpg

PeteVamped
08-04-2009, 09:08 PM
You need to make sure to get the right guide to get you started with the first one. There are many guides out there some offer a gurentee that you will not cause engine damage. It is just a matter of finding the right one. If you do not feel comfortable trying your hands at hho first you may want to try converting to a simpler alternate source which would be electric. I have done some extensive work on many kits which you cn find from both my blog and the main site. Also if you have any questions please feel free to contact me my email is on my main page. I will do the best I can to guide you through the process further. I do recommend you first try using one of the kits out there.

Jager
08-04-2009, 09:20 PM
I'm testing on an OBD1 1990 Bronco II, I figure if I blow it up or burn it out, Oh well.

I have been experiencing a ping at high load acceleration, climbing hills ect....

I pulled the plugs to find them lean burning, pitted and chalky white... yikes not good.

These are old plugs and the gap was way open. I adjusted the gap to factory 0.044 (any suggestion on gaping plugs to suit HHO)

From what I'm gathering I should manually retard my timing seeing as I have a older OBD1 system.. any suggestions on how fair back I should twist the cap? I thought to start off I would twitch it back 1/2 degree to see if that would quiet the ping. I'm running 87 octane.

Thanks for the thread and your infinite wisdom and knowledge,

jager

Roland Jacques
08-05-2009, 10:05 AM
Thanks Q-Hack, I learn something new all the time around here.

I find the whole octane and stoichiometric definitions confusing, then applying them to the variables of HHO boosting. I allways thought of stoichiometric as being the ideal mixture for burning a gases, whether gasoline, H2, ... the more i read that does not seem to be the correct definition but I'm not sure. And part of octane rating is the ability for the gases to burn and not explode once ignited how does that fit into mixing HHO with gasoline? Sometimes It seems the more i learn the less i know.

Roland Jacques
08-05-2009, 09:35 PM
Q-Hack, can you reference any info on the HHO octane? I dont understand how H2 or any gases can be octane rated without O2 in the mix. stoichiometric?

blagojg
10-12-2013, 07:30 AM
My hho damaged intercooler, because of corodion effect of electrolyte, and HHO was ignited by return gases from EGR just before entering the engine and intake was blasted with holes like granate :(
Car is MB CLK 2.7 CDI , Turbo diesel