Bad Gas Alert System?

[DEFYANT]

Can this be done?

I have been reading some old threads where some of us got bad gas. Either crappy quality or mistaken octane purchase to the station putting the wrong octane in the wrong tanks.

I began to wonder if there was a way to monitor the quality of the fuel in the tank.

We have monitors and guages for everything else. The most recent being the Watch Dog buzzer for the electric water pumps some of us run.

So why not something that can tell us if we got the wrong octane?

[metroplex]

When your engine makes the sound of the sign hitting the guy's head :lol: you know the gas is bad.

[DEFYANT]

When your engine makes the sound of the sign hitting the guy's head :lol: you know the gas is bad.
By then, it could be too late. Just ask that guy with the VT car.... He may have gotten bad gas. Also, sometimes you can not hear detonation.

If some kind of alert is given before you get "other" clues, it could save you alot of money.

[grampaws]

You will Hear it!!:o

[BigCars4Ever]

Can this be done?

I have been reading some old threads where some of us got bad gas. Either crappy quality or mistaken octane purchase to the station putting the wrong octane in the wrong tanks.

I began to wonder if there was a way to monitor the quality of the fuel in the tank.

We have monitors and guages for everything else. The most recent being the Watch Dog buzzer for the electric water pumps some of us run.

So why not something that can tell us if we got the wrong octane?
I have read that Ocatne testing is still done with a 1 cylinder motor made to test ocatane. They start the motor and adjust the timing until it knocks. It is still the only accurate method to test octane rating of fuel.

[dwasson]

Analyzing fuel is more complicated than you'd think. When I worked with the Army one of the groups I supported was developing a Captured Fuels Analysis System. The challenges they faced were interesting. I think that the completed system ended up filling a large suitcase.

[MARAUDERCHICK]

I'm not even gonna comment on what I thought THIS thread was about!!

Hee hee hee......:nono: <---shame on me!!! :rolleyes:

[metroplex]

I'm not even gonna comment on what I thought THIS thread was about!!

Hee hee hee......:nono: <---shame on me!!! :rolleyes: Is there such a thing as good gas in your context? :mad2:

As for the VT engine guy, his engine knocked and stalled out.

Unless you use diesel fuel or water instead of gas, lower than normal octane gas should not do that. Don't the Marauders have knock sensors too?

My 00 Vic will knock at higher loads and RPMs with 89 octane but runs fairly well on 89 octane in the city. Sunoco fuels seem to be of very consistent quality. I use 93 octane fuel to prevent the knocking at higher loads and RPMs.

[RF Overlord]

I have read that Ocatne testing is still done with a 1 cylinder motor made to test ocatane.

You mean like this one (http://www.waukeshaengine.dresser.com/internet/businessunits/waukesha/pages/applications/products/fueltesting/f1f2.cfm)?

[Rider90]

I have one of those, I call em' passengers...they let me know :bop:

[Petrograde]

You mean like this one (http://www.waukeshaengine.dresser.com/internet/businessunits/waukesha/pages/applications/products/fueltesting/f1f2.cfm)?

Think it'll fit in the trunk? :P

[Donny Carlson]

I'm not even gonna comment on what I thought THIS thread was about!!

Hee hee hee......:nono: <---shame on me!!! :rolleyes:Yeah, I was going to say I have one..... called "a nose."

Course, with me, most people are alerted by a sound similar to ripping canvas.

A short Google search produced this actual product for sale:

http://www.getpranks.com/images/items/big/detector_big.jpg (http://www.getpranks.com/buy.cfm?id=14)

[MENINBLK]

The only way to accurately measure octane is with compression.

Fuel Octane = The amount of compression it takes to ignite the fuel.

86 octane will ignite easier in a high compression engine,
where 93, 94, or higher octane will never ignite in your average engine.

This ignition under compression is called pre-ignition or 'pinging'.
The pinging noise is cause by the detonation of the fuel/air mixture,
earlier than it was due, and the rapidly expanding mixture puts a fair amount of
pressure on the intake valve, slamming it closed, and also slamming on the piston head.
If this goes on without correction, it can severly damage an engine.

Take our engine with its 10.5:1 compression.
91 octane if required as a minimum to keep the engine
from knocking itself apart with pre-ignition.
Higher octane will surely guarantee no pre-ignition provided your engine
is well maintained, and running within normal limits.
OVERHEATING can INCREASE compression and lead to knocking,
as some of us found out when our thermostats went bad.

Blended fuels can also lead to pre-ignition because what is used for the blend,
can have a LOWER ocatne than the fuel, causing the blend to be a lower octane.

So just beware of the fuel you are buying, and only buy from
a reputable service station that turns over fuel fairly quickly.
This will help you to avoid having any pre-ignition at all.

[BigCars4Ever]

You mean like this one (http://www.waukeshaengine.dresser.com/internet/businessunits/waukesha/pages/applications/products/fueltesting/f1f2.cfm)?Wow! I never imagined they would be so complex but there it is.

[DEFYANT]

Thanks for al the responses. So much for that idea.

[torinodan]

Well, couldn't someone just wire a simple LED light system to the knock sensor circuit so when it flashed at WOT or whenever you could back off the gas?? You could be able to do this so you don't have to wait on it to ping and blow something apart. Right? Humm, sounds simple enough. Kindof like an oil pressure light or something. I don't know. I love LED's

[David Morton]

Actually I thought this thread would be about us warning each other about bad gas as was done last year with the Shell fuel being sold here in the south with high sulpur content. We could make it a sticky thread and let each other know when we got a bad tank, where and what kind it was, low octane suspect or high sulphur (eg. "rotten egg smell").

Marauderchick, your mind is telling you something. Maybe you're beginning to suspect that your boyfriend telling you that "real love is when she begins to like the smell of you farts" isn't quite right.

:lol:

[DEFYANT]

Actually I thought this thread would be about us warning each other about bad gas
Sort of like "Bad Gas Alert Thread"?

Good idea....

[David Morton]

Sort of like "Bad Gas Alert Thread"?

Good idea....On second thought, maybe we oughta run this past Logan first.

Dang oil company might take offense and send out a hit squad of lawyers and shut him down. :shake:

[dwasson]

Well, couldn't someone just wire a simple LED light system to the knock sensor circuit so when it flashed at WOT or whenever you could back off the gas?? You could be able to do this so you don't have to wait on it to ping and blow something apart. Right? Humm, sounds simple enough. Kindof like an oil pressure light or something. I don't know. I love LED's

Having a LED light when the computer sensed a knock wouldn't be that informative. However, it wouldn't be that hard to latch that signal and build a delay into the circuit that would keep the LED lit for some period of time. A 10 second delay would be good. That way, instead of a vague flash you would get a solid LED for a while.

[torinodan]

Having a LED light when the computer sensed a knock wouldn't be that informative. However, it wouldn't be that hard to latch that signal and build a delay into the circuit that would keep the LED lit for some period of time. A 10 second delay would be good. That way, instead of a vague flash you would get a solid LED for a while.
http://www.california.com/~eagle/knock.html
http://www.gnttype.org/techarea/projects/projectspage.html
http://www.gmcmhphotos.com/gallery/showalbum.php?uuid=mrerf&aid=59

All ready been done. Just need to visit Radio Shack and get parts. Oh, and get a little help with the schematics. The schematics for my helocopters don't go into detail this far.

[dwasson]

I love the idea of the audible alarm too. That would be annoying enough that you would back off.

[torinodan]

So, who wants to go in and make some and figure out how to A: wire it in, or B: use the stand alone system thats shown here on the links?

[kartherma]

I saw a special on the history channel a month or so ago about gas and learned alot about the "octane" rating.

In a nutshell:

Gasoline is made from the hydro-carbons of 7 and 8 length carbon atoms---> Heptane and Octane

Heptane likes to detonate witout a spark under high compression situations, especially with residual heat present.

Octane is somewhat the opposite and doesnt like to detonate without a spark.

(The above is a generalization)

In the process where we break down crude oil (a distilling process where we "boil" crude under high pressures) we wind up breaking up larger hydro-carbon chains into the 7 and 8 length chains. Unfortunately, it turns out nature has made it such that we get far more heptane than octane when we do this.

The Octane "rating" is basically a comparison. 100 is referenced to 100% Octane while 0 is referenced to 100% Heptane.

They blend the two, add their additives and then test the fuel mixtures against that reference with respect to how that fuel performs.

So basically 100% Octane will undergo detonation just like 100% Heptane, but under heavier heat/compression values.

There was a phase where we added lead to the fuel where the lead helped to make the fuel undergo far more heat/compression witout detonation. Later we discovered that it put alot of pollutants into the environment and subsequently stopped using it. It is my understanding that many race fuels perform at higher octane ratings due to lead or other similar additives. (on a side note I have found a lead additive on the shelf in checker/kragen auto and auto zone in Arizona and I am interested in trying it out...)

But we dont use lead any more and in many states it is counter productive to get past emission controls while using aftermarket lead additives, so for many of us this is not an option.

Another way around the detonation issue they said was to make the spark come later in the piston travel. I am not sure exactly what that means, but I do know that the fuel injection is one way to help since the chamber should remain relatively fuel deficient until the injector opens and sprays atomized fuel into it. So if you can wait long enough as the piston travels through top dead center and then back down the bore, you can get away with higher compression ratios since the cylinder volume is now expanding due to the piston travel. Then the spark comes and bang. (draw backs here are obvious in that the further the piston is in its down stroke shortens the time the force will be applied to the piston from the combustion of the gas).

I read in another article (about NOS) that detonation can be also avoided through the use of extra fuel- somehow it keeps the cylinder cooler I guess (dont know...) and also through the use of some after market products that spray down the cylinder essentially with a water/alcohol mixture. Some of our members I have seen write about these systems installed on their Marauders.

Interestingly, the article on the NOS made claims that a wet system can actually help prevent detonation through the same wetting down principle when applied with the right tuning---> primarily retarding the ignition to later in the stroke.


I hope this helps. It is all info I got watching one history channel show for an hour and from just a few articles in some of the muscle car mags.

be good!

curt

[DefyantExWife]

woops, I wandered into this thread thinking it was about something entirely different... and way funnier :baaa:

[David Morton]

DO NOT USE ANY LEAD ADDITIVE IN YOUR FUEL SYSTEM!

It will cause your catalytic convertors to clog up, plugging your exhaust system. Lead and platinum don't like each other, and platinum is what's inside the CATS doing all that converting. It'll also destroy your O2 sensors.

Contrary to popular belief, lead was originally added to gasoline early in the 20th century to make the valves last longer. On a microscopic scale the little balls of lead cushioned the blow between the valve and the head. Nowadays heads have hardened seats and the valves are better and lead isn't needed.

Later on, in the 40s or 50s a chemical that increased octane was invented that had lead in it, killing two birds with one stone hence the myth that lead increases octane. It doesn't. There's plenty of good octane boosters that don't need or use lead and anybody that say theirs is better because they use lead is taking advantage of peoples ignorance.

If they are using lead, they are violating a federal law that NO STATE can exempt.

Besides, why would anybody want to put lead in the atmosphere for the children to breathe?