Mustang on Leaded Fuel...>help
i got a modified 5.0 that i drive around as a daily driver....once in a while when i do street races i put a little bit of leaded fuel in the taank for i little more power.....i can notice the power right away..
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s this a good idea or not,,,,its fuel injected so that problem is out of the way.... im trying to figure out if this will cause any longtime problems for my car...
Re: Mustang on Leaded Fuel...>help
Quote:
Originally posted by Mustang5.O
........ i put a little bit of leaded fuel in the taank for i little more power.....i can notice the power right away..
Ahhhh...........mythology vs reality! This thread is loaded with it. Not to poke fun at anyone, I realize sometimes we write stuff that doesn't exactly come out the way we intend.
Using higher octane fuel (deal with lead later) won't change power output in your engine unless something in the engine changes to increase it's efficiency. There's nothign magic and powerful in that octane stuff, whereever that comes from (it's actually a reference chemical used as a standard to measure against). Internal combustion engines only utilize a fraction of the available energy in a unit of fuel, say 35-40%. Higher static compression is one way to increase that efficiency. And that's what higher octane fuels were designed to allow. Of course, a load of fuel in your tank won't do that. In theory, a "smart" computer control module could change timing (dynamic compression ratio) and extract some greater level of efficiency, but we're talking small percentages here. From what I've read the ccm in a '90 Mustang doesn't do that, but I don't have personal experience with that. If you're feeling any "power right away" it's probably due to your wallet being lighter and your brain needing some gratification. In some circles that's called stroking the dog to feed the cat (familized version).
Now the lead thing. (abreviated version, I'm short on time this morning) These myths just don't want to go away, I guess because folklore is so comforting. The ONLY reason tetraethyl lead was introduced into gasoline was that it was the most economical chemical compound that contributed to higher octane ratings of fuel. All the BS about lubrication is just that..........BS. In fact, when all the science guys were searching for the "magic potion" to increase octane rating during the early part of the twentieth century, tetraethyl lead wasn't their first choice. As often happens there was significant difference of opinion in the community. Lead, even then was know to be hazardous (though not hysterically so). And it contributed to significant depositing in the engine and exhaust system. Since it was so inexpensive it won out anyway. The science guys figured out a way to put another additive in the additive to help keep deposits to a minimum. They're called scavengers, because they scavenge the unwanted deposits out of the combustion chamber. The main reason for bringing this up is that this whold fairy tale thing about the magic lubrication qualities of lead is bunk. The formulators of gasoline did as much as they could to get that stuff out of the engine. Since they weren't 100% successful, there were some deposits left behind. Those deposits, consider them contaminants, dirtied the exhaust valve seat and face which kept the two hot surfaces from "welding" together. It's that welding and subsequent tearing that caused exhaust valves and seats to errode. Dirty surfaces don't weld well, that's all lead contributed. I suppose if you're really stubborn you could twist that into a lubrication scenario of you wanted to. Note too that lead oxide(the result of the burned lead compound) doesn't have any contact with a correctly functioning intake valve.
In order to get the lead out two primary chemical compounds were used. Ethylene dibromide or ehtylene dichromide. The kept most of the lead in a gaseous state for a while so that the exhaust flow would carry it away. Of course these halogenated compounds became corrosive in the presence of water...........which the combustion process is loaded with. Wonder why spark plugs and exhaust systems last longer now a days (probably a question more meaningful to geezers). Sure there's an element of better materials (platinum plugs and aluminized or stainless exhaust) but it's also due to less corrosive elements in the combustion/exhaust stream because of the abscense of those lead scavengers.
One other minor nit, higher octane fuel has little to nothing to do with preignition. Higher octane fuels deal with controling the rate of fuel ignition AFTER the spark plug fires. Preignition, by it's definition, is prior to the spark plug firing.
leaded gasoline and octane
Geez, what's up with you guys? I loved leaded gasoline and I wish they still dispensed at the pump. My 327 has stock 11:1 compression and it loved 102 Sunoco when I could get it. Even 96 octane ethyl let me run 12 degrees initial advance. I can only run 4 degrees on the high octane unleaded crap they sell now; there's gotta be some difference somewhere.
Yeah, I know all about lead pollution from gasoline, but I never knew of anybody that died from it. We all used to wash parts it the stuff and we didn't even get sick from it. Lead will kill you alright, you've just got to take it in the right form, like lead acetate for instance. That stuff will go right through your skin and into your bloodstream in a hurry. But, they didn't put lead acetate in leaded gasoline, they used tetraethyl lead.
And there is the reason leaded gasoline worked so well to control combustion in high compression engines in the first place. Lead is simply the metal atom that the four ethyl functional groups are bonded to. Breaking the bonds from the lead to the four ethyl groups is what slows the combustion process. The metal molecule could have been antimony just as well as lead, possibly even cadmium or zinc. Lead was probably chosen because of economics alone.
If everybody is so concerned about air pollution, especially the self-righteous, federally funded EPA; then how come someone doesn't yell about all the jet airliners spewing hundreds (thousands?) of tons of hydrocarbons into the stratosphere every day? Would it be economic suicide to impose smog controls on the airlines? I bet it would, so they go unregulated by the EPA and you get smog controls on your lawnmower and cannot cook out on a bad air day. Hoo Boy! What a system we've got!
Anyway leaded gasoline is not the demon it's been made out to be, or I'd be dead instead of 50. High octane allows for high compression which allows for more horsepower period. If you think octane rating doesn't matter, fill your tank with hexane, it has an octane rating of about 0. Where do you get hexane? Coleman lantern fuel is mostly mixed hexanes, you can try that. I guarantee it won't even run good in a lawnmower, and it will absolutely destroy an automobile engine. Ever hear of anyone running on drip gasoline or casinghead. Same stuff more or less, just more impurities.
You can put 2,2,4 trimethyl pentane (isooctane) in a high compression engine like my Nova's and it will not ping or knock when you lug it in 4th! I know this from my own experience, I've burned a couple of gallons of the stuff contaminated with tetracholoroehthylene (TCE) from the EPA lab that I worked in for 14 years as a chemist. Isooctane has a octane rating of 100 and is the standard used in the motor octane rating of gasoline to this day. The 0 octane standard is n-heptane, but n-hexane could have been used just as well. What's the idea behind telling motorists that higher octane gas won't help your performance? I don't know, maybe they figure that the higher octane fuel by allowing greater initial advance, will cause more air pollution? That' my best guess because I really don't know for sure, even after 25 years of living with unleaded gasoline.
As to the original question of this thread, leaded gasoline will shorten your plug life to may 1/6 of what you'll get with unleaded. If you still have a catalytic converter(s), the lead will eventually and irreversibly poison the platinum/rhodium catalyst, and render it useless. Some types of converters (GM) will also stop up with extended lead use, although I don't think Ford converters are so affected. And leaded gasoline will generally dirty up your engine (internally) more than unleaded, specifically in the combustion chambers of the heads. I suppose it could leave deposits in your fuel injector nozzles as well, but maybe not. Anyway, these days, since leaded gasoline is history, I really can't see any advantage to using it in your engine, especially since so many years of engineering design has gone into making engines live on unleaded fuel. You would probably gain about as much benefit by dumping in a gallon of acetone into your gas tank as you would using the lead additive. I don't think I would do it myself.
Randy