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Discussion Starter #1
Safe to use on our Rovers?

Leaded. Not Unleaded. They have this in Las Vegas. Sunoco Fuels $7.99 Gallon


P.S. I have no cats.
 

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very disco
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lolol you are always trying to put strange **** in your rover

are you knocking or having other issues? my understanding of leaded gasoline was to prevent pre-combustion of the fuel in the engine.

some folks say lead is bad for the engine, i think all folks say lead is bad for the environment.

i can buy leaded gasoline at this ranch station down highway 18, but that doesn't mean it's legal to run in my disco. it's for agricultural and marine use only.
funny they'll allow trucks driving around in fields of our food to exhaust poisonous lead, and boats in our lakes... but not on the street.
 

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Bleeds Green
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Lead was used in fuel to reduce knocking (pre-combustion) as the reverendALC said, and also to help reduce internal wear because oil wasn't the best back in the day. As an example of reducing internal wear; valve seats weren't hardened and the lead in the fuel cushioned the valves to keep them from slamming themselves to death into their seats.

Today, lead is added to race fuel because it easily and cheaply adds about 20 points of octane. That 110 octane gas was probably just 87 until they added lead to and upped the price.

Why not use leaded fuel? Aside from the environmental implications, lead absolutely destroys catalytic converters and damages O2 sensors. As little as two tanks will completely toast your cats. Continued use can cause the cats to heat up to the point where they can cause a fire.

To answer your question, no, leaded fuel is not safe for any vehicle designed to run with catalytic converters (vehicles manufactured for the US from 1975 onward have catalytic converters).

But for you since you have no cats, sure. Give it a try if you want. You'll probably need new O2 sensors before long if you do. Or just go get a bottle of octane booster from a car parts store. It'd certainly be cheaper than paying $7.99 a gallon, won't ruin your O2 sensors and is much better for the environment. Anything above 100 octane is probably wasted in your engine though because our Discos don't have the high compression required to make the most out of higher octane fuel.
 

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Discussion Starter #4
Lead was used in fuel to reduce knocking (pre-combustion) as the reverendALC said, and also to help reduce internal wear because oil wasn't the best back in the day. As an example of reducing internal wear; valve seats weren't hardened and the lead in the fuel cushioned the valves to keep them from slamming themselves to death into their seats.

Today, lead is added to race fuel because it easily and cheaply adds about 20 points of octane. That 110 octane gas was probably just 87 until they added lead to and upped the price.

Why not use leaded fuel? Aside from the environmental implications, lead absolutely destroys catalytic converters and damages O2 sensors. As little as two tanks will completely toast your cats. Continued use can cause the cats to heat up to the point where they can cause a fire.

To answer your question, no, leaded fuel is not safe for any vehicle designed to run with catalytic converters (vehicles manufactured for the US from 1975 onward have catalytic converters).

But for you since you have no cats, sure. Give it a try if you want. You'll probably need new O2 sensors before long if you do. Or just go get a bottle of octane booster from a car parts store. It'd certainly be cheaper than paying $7.99 a gallon, won't ruin your O2 sensors and is much better for the environment. Anything above 100 octane is probably wasted in your engine though because our Discos don't have the high compression required to make the most out of higher octane fuel.

Great news

:grin



Rover gets a full tank of 110 octane leaded tomorrow.
 

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Discussion Starter #5 (Edited)
..
 

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Bleeds Green
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"some folks say lead is bad for the engine, i think all folks say lead is bad for the environment."

"You'll probably need new O2 sensors before long"

"Anything above 100 octane is probably wasted in your engine"

Great news Rover gets a full tank of 110 octane leaded tomorrow.
:dunno:
 

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Discussion Starter #7
"some folks say lead is bad for the engine, i think all folks say lead is bad for the environment."

"You'll probably need new O2 sensors before long"

"Anything above 100 octane is probably wasted in your engine"



:dunno:

Ran 100 oct. from Rebel Oil many times and it makes the engine run smoother and gets better MPG. But of course the MPG gain is offset by the cost. I would also imagine it cleans out the fuel system better. I have o2 spacers so that should not be a problem.

Time to filler up :smile
 

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Expert Crate Digger
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You lost me at $7.99/gallon...
 

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very disco
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haha a 10% improvement in economy for a mere 200% increase in price.
 

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Discussion Starter #11

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Drives like an old man
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Higher octane has NOTHING to do with cleaning out the fuel system. Come on, man. Read a book. High octane is only useful in very high compression engines, and only to prevent pre-ignition knock. It won't make your little 4 liter do anything differently.
 

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Discussion Starter #13
Higher octane has NOTHING to do with cleaning out the fuel system. Come on, man. Read a book. High octane is only useful in very high compression engines, and only to prevent pre-ignition knock. It won't make your little 4 liter do anything differently.[/QUOTE

Rover runs smoother at lower RPM's with better MPG with high octane gasoline. Sunoco's 110 octane leaded gas has 0% ethonol.
 

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lolol you are always trying to put strange **** in your rover

are you knocking or having other issues? my understanding of leaded gasoline was to prevent pre-combustion of the fuel in the engine.

some folks say lead is bad for the engine, i think all folks say lead is bad for the environment.

i can buy leaded gasoline at this ranch station down highway 18, but that doesn't mean it's legal to run in my disco. it's for agricultural and marine use only.
funny they'll allow trucks driving around in fields of our food to exhaust poisonous lead, and boats in our lakes... but not on the street.
Well, considering that the number of farm vehicles is MUCH lower and the frequency their engines are ran is MUCH lower it makes perfect sense. Not like plants absorb lead fumes.

Cows pollute more than cars, yet their legal in every state, I think that's a bit more funny.
 

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Ran 100 oct. from Rebel Oil many times and it makes the engine run smoother and gets better MPG. But of course the MPG gain is offset by the cost. I would also imagine it cleans out the fuel system better. I have o2 spacers so that should not be a problem.

Time to filler up :smile
Well, it doesn't get any better MPG nor does it make any more power.... all you did was waste a few dollars and put some lead in the air. We're talking about tetraethyllead.


In my car, leaded fuel has some benefits, I'd run it only on a race track where it has purpose. In your street vehicle it served no purpose. Not sure why you felt the desire to do it. It won't clean out your fuel system either, though a few cheaper store bought chemical compounds would have.

By the way ethanol reduces knock too...... there's a lot of extremely high hp street vehicles making over 1000whp running 100% ethanol for this reason.

In my 786whp S2000 I use leaded fuel or other specialty fuels to reduce pre-ignition because my engine is making about 500hp per liter at the crank. When it was stock at 11.1:1 compression and running 8psi of boost you might imagine it was barely avoiding knock on 91 california pump, though it was fine for quite a few years. I was able to squeeze 400whp on pump fuel. After a full build, an 11k redline, mildly lowered compression and a better turbo system, I'm at 29psi most days but can go higher depending on fuel source for which I've various tunes. In this kind of vehicle, again, leaded fuel makes sense assuming I need the extra hp for a track day or similar. Generally it runs 500whp+ on pump fuel, you have to figure you pissed your dollars away right?
 

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Higher octane has NOTHING to do with cleaning out the fuel system. Come on, man. Read a book. High octane is only useful in very high compression engines, and only to prevent pre-ignition knock. It won't make your little 4 liter do anything differently.[/QUOTE

Rover runs smoother at lower RPM's with better MPG with high octane gasoline. Sunoco's 110 octane leaded gas has 0% ethonol.
This is absolutely bogus with one exception, if your motor is knocking, it may help that issue but that issue could be solved a few different ways for far less money.
 

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very disco
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maybe WLADiscoII99 left his 1000bhp engine modifications out of his signature? maybe it's in there somewhere... tl;dr hehehe
 

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Discussion Starter #18
This is absolutely bogus with one exception, if your motor is knocking, it may help that issue but that issue could be solved a few different ways for far less money.

Buy min. 100 Octane Rebel Gas 7.99 Gall. Then listen to your engine and watch your RPM and MPG - then tell me it's bogus.

Even mixing 50/50 92 Octane + 100 Octane you will feel a difference from 92 Octane. It makes a big difference in performance and MPG.
 

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Bleeds Green
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It makes a big difference in performance and MPG.
Higher octane fuel can make engines run a little better and can give a little boost to MPGs, but there is certainly a point of diminishing returns. Since I don't have any numbers from your Disco for "regular" MPG and horsepower; here are some thoughts based on my Disco's real world performance:

In town I get about 12mpg on 91 octane. For this thought experiment, I'll assume yours is the same. I usually fill up when it takes about 18 - 20 gallons. I'll assume you do too, but I'll use 20 gallons for easier math.

If it takes 20 gallons to fill my tank at $3.50 per gallon for 91 octane (current-ish price in Las Vegas where you are for premium gas), that's $70 per tank. At 12mpg I'd go 240 miles. $70 / 240 miles = 29¢ per mile for fuel.

Let's say 110 octane gets a whopping 17mpg in town at $8 per gallon. 20 gallons of fuel would cost $160. At 17mpg, each tank will carry you about 340 miles. $160 / 340 miles = 47¢ per mile in fuel costs. That's a 162% increase fuel cost per mile.

To make it worth your while, I'd think you'd want to get nearly a 162% increase in performance from your engine. Assuming a "normal" 12mpg and 182hp you'd need to see 19.5mpg city and 295hp. I kinda doubt you see either of those figures on 110 gas.

Your Disco's engine has a 9.35:1 compression ratio. According to what I can find about octane and compression ratios, the benefit from increased octane caps out at about 100 octane for your compression ratio. Anything above 100 octane wasted because you don't have the compression ratio to make it work. That means that 10% of the octane is wasted. It's like throwing ~$16 on the ground every time you fill up with this race gas.


Some interesting info from a company that builds pistons:

Octane, by itself is not a function of fuel that adds power. Octane is added to fuel to prevent detonation. If the engine suffers from detonation or knocking due to the use of a lower grade gasoline, adding octane will restore that power. Conversely, adding a higher octane rated fuel to an engine that is not suffering from detonation problems will not result in additional power. A more common situation is that adding octane beyond the engine’s requirements generally results in a less efficient combustion process that does not increase power. In certain situations, use of too much octane can result in a slight loss of power! Here is where the “More is Better” theory fails the test.

Much like every other system in a race engine, it is the proper combination of components and fuel that can result in improved power. For example, race gasoline is often blended with oxygenates which have the effect of leaning / changing the fuel’s stoichiometric (or chemically correct) air-fuel ratio. It is often these additives that are responsible for power increases, and not the octane number. Experimenting with fuels with different oxygenate percentages can have a dramatic effect on the actual air-fuel ratio. This gets into a complex story on stoichiometric air-fuel ratio that is beyond the focus of this story, but it is an important issue to be aware of before attempting to custom blend race gasoline.
To make your engine run more smoothly and efficiently it'd be a great idea to reinstate the cats and put the O2 sensors back where they are supposed to go so they can actually do their jobs and tune the engine based on conditions. (Removing your cats might have gained you 18hp at most, but your ECU lost some of its ability to properly tune the engine based on conditions so you might not have gained anything.) Replace your injectors with fresh ones because they are typically good for about 150k miles (this makes a big difference), change your air filter, get new plugs, plug wires and coils and get your heads refurbished because valve springs and seats wear out, etc. You'd sure would be looking at an expense to do all of that work but it'd probably cost about the same amount as two oil changes worth of miles on 110 gas and you'd actually be investing in making your Disco better for the long term.

I thought this was an interesting thought experiment and something I'd like to know more about which is why I wrote this post. I don't expect you to change your position based on the data.

Several edits for typos and clarity
 

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Discussion Starter #20
Higher octane fuel can make engines run a little better and can give a little boost to MPGs, but there is certainly a point of diminishing returns. Since I don't have any numbers from your Disco for "regular" MPG and horsepower; here are some thoughts based on my Disco's real world performance:

In town I get about 12mpg on 91 octane. For this thought experiment, I'll assume yours is the same. I usually fill up when it takes about 18 - 20 gallons. I'll assume you do too, but I'll use 20 gallons for easier math.

If it takes 20 gallons to fill my tank at $3.50 per gallon for 91 octane (current-ish price in Las Vegas where you are for premium gas), that's $70 per tank. At 12mpg I'd go 240 miles. $70 / 240 miles = 29¢ per mile for fuel.

Let's say 110 octane gets a whopping 17mpg in town at $8 per gallon. 20 gallons of fuel would cost $160. At 17mpg, each tank will carry you about 340 miles. $160 / 340 miles = 47¢ per mile in fuel costs. That's a 162% increase fuel cost per mile.

To make it worth your while, I'd think you'd want to get nearly a 162% increase in performance from your engine. Assuming a "normal" 12mpg and 182hp you'd need to see 19.5mpg city and 295hp. I kinda doubt you see either of those figures on 110 gas.

Your Disco's engine has a 9.35:1 compression ratio. According to what I can find about octane and compression ratios, the benefit from increased octane caps out at about 100 octane for your compression ratio. Anything above 100 octane wasted because you don't have the compression ratio to make it work. That means that 10% of the octane is wasted. It's like throwing ~$16 on the ground every time you fill up with this race gas.


Some interesting info from a company that builds pistons:

To make your engine run more smoothly and efficiently it'd be a great idea to reinstate the cats and put the O2 sensors back where they are supposed to go so they can actually do their jobs and tune the engine based on conditions. (Removing your cats might have gained you 18hp at most, but your ECU lost some of its ability to properly tune the engine based on conditions so you might not have gained anything.) Replace your injectors with fresh ones because they are typically good for about 150k miles (this makes a big difference), change your air filter, get new plugs, plug wires and coils and get your heads refurbished because valve springs and seats wear out, etc. You'd sure would be looking at an expense to do all of that work but it'd probably cost about the same amount as two oil changes worth of miles on 110 gas and you'd actually be investing in making your Disco better for the long term.

I thought this was an interesting thought experiment and something I'd like to know more about which is why I wrote this post. I don't expect you to change your position based on the data.

Several edits for typos and clarity

I understand it's a waste of money. But if 100 octane or 110 was the same price as premium it would be a bargain. And the facts are the engine does run a tad smoother and I'm getting a bump in MPG. But I understand it's a waste of money so I will only do it every other month or so.

No way I would ever reinstall the cats. I have a pair of fakes on there. So there is no way for anyone to know. It runs better and sounds awesome without the cats. I gotta make a video of it at idle so you can hear what I'm talking about. Or you can look at the ones on you tube. My set up is a straight pipe with a Flowmaster at the end for a booming sound with a little tin and Gurgle.

It sounds too cool to ever go back to cats. Not to mention - I got $200 for the Cats at the recycling Facility. Evidently the 99 Land Rover used allot of precious metals compared to modern cars.
 
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