Quote:
Originally Posted by usedgeo
I have been running real heated air and as Diamondlarry pointed out, when both water and air are above 200 it does not run all that well. I have never observed a timing retard on my car. My timing never makes it as far as some others report. The max I ever see is 34 degrees. The reported mileage is good though. Here is a recent picture of my plugs. It looks like it is running a bit lean. It has a slight miss at the warmest temps. I am hoping for Somender grooves to help with that. The ceramic is white but three of the ground electrodes are dark. There is a bit more about the plugs here..
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http://www.hydrogen-boost.com/newsletter.html
"Will operating my vehicle at a leaner mixture with Hydrogen-Boost, cause damage to my valves?
With Hydrogen-Boost seeking to run on the leanest air/fuel mixture that has acceptable torque and power, in pursuit of the best possible gas mileage, we have had repeated questions from misinformed customers concerning whether they would burn their valves by running the extra lean mixture.
I am sure the misinformation comes from the aviation field. Being an aviator until last year's near fatal experimental aircraft accident, I know that piston engine aircraft take off and climb at maximum power, and cruise at a leaner mixture, watching the EGT gauge to insure a safe temperature. Of course we all assume that safe temperature means a temperature that doesn't burn the valves.
This information gets us to assume that an electronic fuel injected engine runs at the rich mixture that is cool enough to protect the valves from burning. Most also assume that if we lean out the mixture we will be in danger of burning the valves. A too hot exhaust gas temperature also would indicate a too hot combustion temperature that happens to produce NOx, the oxides of nitrogen that are considered as toxic pollution.
What most of us don't know is that during warm up and acceleration the EFI (electronic fuel injection) engine does indeed run with a rich mixture, but during cruise the engine control unit (ECU) runs in what is called closed loop operation, which targets a 14.7 to 1 air fuel ratio. This ratio is called stoichiometric, meaning that there is a perfect mixture of air and fuel to insure complete combustion. This also happens to be the perfect mixture to get the highest temperature of combustion, and therefore the highest exhaust gas temperature (EGT). Any leaner (more air) mixture will cause a cooler combustion, and any richer (more fuel) mixture will also cause a cooler combustion.
The following quote was obtained from
http://www.sdsefi.com/techegt.htm and is chemically accurate:
Some gauge manufacturers say you should tune to achieve maximum or peak EGT for maximum performance. This is incorrect. Peak EGT generally occurs at an AFR of around 14.7- 15.0 to 1 on gasoline. This is far too lean for maximum power and is dangerous under continuous WOT conditions. Many people think that the leaner you go, the higher the EGT gets. This is also incorrect. Peak EGT occurs at stoichiometry- about 15 to 1 for our purposes. If you go richer than 15 to 1, EGT will drop and if you go leaner than 15 to 1 EGT will ALSO drop. It is VERY important to know which side of peak EGT you are on before making adjustments. It is safe to say that peak power will occur at an EGT somewhat colder than peak EGT.
As you can probably figure out by now, leaning the mixture from the target 14.7 to 1 will NOT cause a hotter exhaust nor will it cause you to burn your valves. This is not to say that leaning the ECU's program under all conditions will cause a cooler exhaust. There is one condition that could be hotter and that would be running at WOT (wide open throttle) at 14.7 to 1 instead of the programmed 13 to 1. A continuous running at this condition might indeed burn your valves.
But how often would a mileage conscientious driver equipped with Hydrogen-Boost want to run at WOT for extended periods of time at 14.7 to 1 mixture? First of all a conscientious driver would be following the driving tips in the manual which discourages WOT driving all together, say nothing about an extended WOT operation. Also if a Hydrogen-Boost system is adjusted properly, it will be running at a much higher (leaner) mixture than 14.7 to 1, even at full throttle.
Being a research scientist, I don't like to take anyone's word for anything so I have ordered two EGT gauges, both of which can read the temperatures of two sensors. I will verify all that has been written in this newsletter and will report the results in a later issue.
So to answer the original question:
Will operating my vehicle at a leaner mixture with Hydrogen-Boost, cause damage to my valves? NO."
"Am afraid that the MYTH of valve burning and the reasons may have had its
roots back when cars were tuned by hand and people did lots of things wrong
when they adjusted the settings. The popularity of the myth might have its
origin after seeing an acetylene torch cut thru steel. Not stainless tho. A
torch won't normally cut stainless. BTW I learned welding in the Air Force.
My times on dynos shows that a lean mixture leads to misfires that may occur
every other cycle and give a tell tale bang out the exhaust.
It is well known that a lean mixture COOLS the combustion temperatures.
The peak temperature happens when the cylinder is running at or slightly richer
than a stoichiometric mixture. Too rich or too lean drops the peak temps.
But the slow burns from lean mixtures may exit past the exhaust valve still
burning and ignite unburned fuel in the pipe or muffler or cat-con.
Modern cars have computers that adjust mixture and engine parmeters without
human help. The sensors feed their data to the computer and the computer
does what it is programmed to do. Unless someone tampers with a car
computer, the engine will behave properly.
My previous Email has a quote from Jack Henry who strongly emphasized the
relationship between good mileage and engine performance. For example, too
lean of a mixture would NOT give good mileage. How could it? Fuel can go
unburned out the exhaust with lean mixtures. When your ScanGauge says you
are getting good mileage, your engine will last the longest possible. SO it
is NOT possible to damage valves or anything else at peak mileage.
Back in San Pedro, we ran engines for days at a time under load at peak
economy without problems in both gas and diesel engines. Louis LaPointe"
If you go too lean you get misfires? I THINK people using Halo plugs can get better ignition with a lean mix. Can anyone verify this?
a new policy....I intend to ignore the nescient...a waste of time and energy. 
Linear Mode
