Fuel quality 1984 vs today

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I wonder how fuel quality has changed during the time I've owned my 1984 Ski Nautique with a 351 Windsor. I've never had any memorable fuel issues, octane always has seemed adequate, and despite alarmist warnings that lead removal would cause valve recession, I've noticed no problems. The advice when lead was removed was get hardened valve seats installed, and assuredly run lead substitute if not. I didn't do either, continue to run E10 87 octane auto pump gas, and it runs great. It has almost 1700 hours on it, and appears to have the same power as the day I bought it. How has fuel changed over the last nearly 40 years beyond the obvious addition of ethanol and the removal of lead? I'll assume some aspects of fuel are worse and some are better. Possibly modern fuel is more tightly monitored and blended more consistently.
 
I The advice when lead was removed was get hardened valve seats installed, and assuredly run lead substitute if not. I didn't do either, continue to run E10 87 octane auto pump gas, and it runs great. It has almost 1700 hours on it, and appears to have the same power as the day I bought it. How has fuel changed over the last nearly 40 years beyond the obvious addition of ethanol and the removal of lead? I'll assume some aspects of fuel are worse and some are better. Possibly modern fuel is more tightly monitored and blended more consistently.
Catalytic convertors came out about 1975. IIRC thats when hardened valve seats started going in production. Leaded fuel was available till around 1988 or so, probably not legal after 1996 at all except for av gas.

The 60's cars probably had more worries about valve seat recession and no lead fuel. But a lot of them needed rebuilds by the 80's. A lot of 60's engines were shot by 100k.
 
How has fuel changed over the last nearly 40 years beyond the obvious addition of ethanol and the removal of lead?

Ethanol was used 40 years ago in some places. And in other places where ethanol wasn't convenient to use they used MTBE.

These both functioned as an oxygenate (required by EPA regulation in some places) and an octane booster, as well as an extender.

Originally, ethanol or MTBE was blended with 87 octane gas. This resulted in something higher than 87 octane, probably closer to 89 octane, but it was still sold as 87 octane.

At some point (late 90s?), the oil companies figured out that they could use the octane boosting effects of MTBE and ethanol to reduce costs (or increase their profit, or both) and started producing "BOB gas". BOB gas is about 85 octane. BOB stands for "before oxygenate blending". When ethanol or MTBE is added to 85 octane gas (10%), it becomes 87 octane gas.

A version of "BOB gas" with a higher octane is designed to be blended with 10% ethanol or MTBE to give you 93 octane premium gas. (I believe that this gas without the ethanol is sold as ethanol-free gas and has an 89 octane rating).

As far as MTBE, that was found to contaminate groundwater and impart an unpleasant taste and odor. The oil companies wanted the Feds to indemnify them from lawsuits relating to MTBE groundwater contamination. The Feds didn't do that, so the oil companies stopped using MTBE and replaced it with ethanol. (There are some states that have since banned MTBE, but it is not banned at the Federal level).

Also, sometime in the 90s the EPA started requiring more and/or better detergents to be added to gasoline, I believe this was in response to problems with fuel injectors getting dirty and the increased emissions that causes.
 
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Its was the EPA's reduction of detergents in the 90's that caused problems with the automakers. EPA's requirement is still a joke. Kinda glad that automakers signed on with toptier. Toptier, depending on additive package, is 2x-3x more than EPA's requirement.

Toptier bringing us back to the 80's deposit cleaning fuel!

Arkansas Billybob was trying to save a few pennies per gallon for the poor people. Another one of those solutions for a problem that doesn't exist, which in turn creates a bigger problem.
 
Its was the EPA's reduction of detergents in the 90's that caused problems with the automakers. EPA's requirement is still a joke. Kinda glad that automakers signed on with toptier. Toptier, depending on additive package, is 2x-3x more than EPA's requirement.

What I found is that EPA implemented a regulation in 1995 that set standards for detergent levels in gasoline. Previously, according to what I read, there was no EPA requirement.. Wiki says: "The new EPA standards required lower levels of detergent additives than were then being used by a few major fuel marketers. When the new regulations came in, most gasoline marketers who had previously provided higher levels of detergents reduced the level of detergents in their gasolines to meet the new standard."

 
I can't speak to the OP's Ford engine, but Chrysler engines had hardened valve seats and unleaded capability starting with the 1973 models. I suspect that they all were by 1974.

I sold my last leaded fuel capable car in 1988. Low-lead auto fuel in the regular 89 PON was still available until something like 1996 in the US. Much later in some other nations.
 
By 1975 at the latest, when catalytic converters became mandatory.

Yes, certainly by the time the '75 car models came out. Half ton pickups were exempted until the 1978 models, then a couple of years later for 3/4 ton trucks, even later for one-ton trucks. My factory shop manual for 1982 Dodge trucks shows the D/W 350 models without cats.
 
Ethanol was used 40 years ago in some places. And in other places where ethanol wasn't convenient to use they used MTBE.

These both functioned as an oxygenate (required by EPA regulation in some places) and an octane booster, as well as an extender.

Originally, ethanol or MTBE was blended with 87 octane gas. This resulted in something higher than 87 octane, probably closer to 89 octane, but it was still sold as 87 octane.

At some point (late 90s?), the oil companies figured out that they could use the octane boosting effects of MTBE and ethanol to reduce costs (or increase their profit, or both) and started producing "BOB gas". BOB gas is about 85 octane. BOB stands for "before oxygenate blending". When ethanol or MTBE is added to 85 octane gas (10%), it becomes 87 octane gas.

A version of "BOB gas" with a higher octane is designed to be blended with 10% ethanol or MTBE to give you 93 octane premium gas. (I believe that this gas without the ethanol is sold as ethanol-free gas and has an 89 octane rating).

As far as MTBE, that was found to contaminate groundwater and impart an unpleasant taste and odor. The oil companies wanted the Feds to indemnify them from lawsuits relating to MTBE groundwater contamination. The Feds didn't do that, so the oil companies stopped using MTBE and replaced it with ethanol. (There are some states that have since banned MTBE, but it is not banned at the Federal level).

Also, sometime in the 90s the EPA started requiring more and/or better detergents to be added to gasoline, I believe this was in response to problems with fuel injectors getting dirty and the increased emissions that causes.

I think BOB as actually an acronym for the rather unwieldy "blendstock for oxygenate blending".

But absolutely there was a time when 87 (or maybe 86) AKI octane was blended with up to 10% ethanol and they would just call it a day. I believe the industry term was "octane giveaway", although they also use that to describe when the octane rating is higher (the whole "minimum" thing on the label) than on the pump.
 
By the mid 70's all engines had induction hardened valve seats for unleaded gas. The original 1975 ,345 international I took apart years ago had the hard seats factory installed.
 
If you remember, gasoline before the 1990s had an amber color. It all looks clear now.

Amoco ran TV ads in the late 1990s talking about the amber color in competitors' gasoline coming from impurities. If those ads told the truth, then today's clear fuels would in theory be better in quality (more pure) than '80s stuff.
 
Its was the EPA's reduction of detergents in the 90's that caused problems with the automakers. EPA's requirement is still a joke. Kinda glad that automakers signed on with toptier. Toptier, depending on additive package, is 2x-3x more than EPA's requirement.

Toptier bringing us back to the 80's deposit cleaning fuel!

Arkansas Billybob was trying to save a few pennies per gallon for the poor people. Another one of those solutions for a problem that doesn't exist, which in turn creates a bigger problem.

I'm pretty sure it wasn't until around 1994 that detergents were actually mandated by the EPA. I used Mobil then because they adverted detergent additives but the pre-Billy Bobs didn't care about your carb/FI'ers nor the air quality in general...

The regulations were weakened under W in order to sell more gas. From: https://omb.report/omb/2060-0275

OMB 2060-0275
Gasoline combustion results in the formation of engine deposits. The accumulation of deposits, particularly in the orifices of fuel injectors and on intake valves, typically results in increased emissions and reduced engine performance. As fuel injectors replaced carburetors in the 1980's, a number of vehicle manufacturers experienced problems with deposit formation. Detergent additives, which had been available for years to control deposits in carbureted vehicles, were improved to accommodate the new technology. However, their use was voluntary and there were no regulatory standards by which to gauge their effectiveness. Congress recognized the importance of effective detergent additives in minimizing vehicle emissions, and added Section 211(1) in the Clean Air Act Amendments of 1990. It required gasoline to contain detergent additives, effective January 1, 1995, and provided the Environmental Protection Agency (EPA) with the authority to establish specifications for such additives. The regulations at 40 CFR 80 - Subpart G implemented certification requirements for detergents and imposed a variety of recordkeeping and reporting requirements for certain parties involved with detergents, gasoline, or post-refinery component (any gasoline blending stock or any oxygenate that is blended with gasoline subsequent to the gasoline refining process (PRC)). All gasolines must contain certified detergents, with the exception of research, racing, and aviation gasolines.
 
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Gas brands worked with the automakers...equivalent of today's toptier.
Cheapskate generic stations used little to none.

EPA baseline was proven pathetic.
Automakers do it again...recommending higher detergents levels creating toptier.

Epa should've left well enough alone.

Too many trust EPA as competent.
 
Gas brands worked with the automakers...equivalent of today's toptier.
Cheapskate generic stations used little to none.

I don't recall any of that. I'm pretty sure some like Mobil and Shell advertised detergent additives in their high octane blends, but a lot of mom and pop gas stations had little or no detergents at all. That may not have been as much of an issue with the carburetor era as they had more tolerances for gunk, and were mainly easy to clean but it became an issue with increasingly sophisticated fuel injection systems....


EPA baseline was proven pathetic.
Automakers do it again...recommending higher detergents levels creating toptier.

They are inadequate but I don't blame the EPA for that, it's the lobbyists maybe...
Epa should've left well enough alone.

Too many trust EPA as competent.

Sure, then Standard Oil will just police itself with extra-leaded gasoline... :D LOL
 
Not Standard oil... the automakers will demand a certain quality level of fuel and make that 'recommendation' in the owners manual, like many have over the last 30 years. Toptier adds to choices. Not much more different than demanding certain 'specs' for oil... any brand you want as long as its SP/Dexos1/GF6/whatever....

And, this thread has nothing to do with lead.
 
Yeah unelected epa officials never ever get anything wrong and.... They never make laws on their own... Which of course they do. .

Because real elected people give them that authorization to do just that.

Delegation of certain aspects of passed laws is where very bad things can and do take place.

No matter who does it. . Both sides are guilty of this stuff.
 
Yeah unelected epa officials never ever get anything wrong and.... They never make laws on their own... Which of course they do.

Being about 90% positive that I've met an delt with more EPA beauocrats than you ever will, I would never, ever say anything of the sort. A bit of cheeky strawman there actually...
Because real elected people give them that authorization to do just that.

Delegation of certain aspects of passed laws is where very bad things can and do take place.

No matter who does it. . Both sides are guilty of this stuff.

I generally agree. But remember elected people need generous donations to keep being elected...
 
Not Standard oil... the automakers will demand a certain quality level of fuel and make that 'recommendation' in the owners manual, like many have over the last 30 years. Toptier adds to choices. Not much more different than demanding certain 'specs' for oil... any brand you want as long as its SP/Dexos1/GF6/whatever....

And, this thread has nothing to do with lead.

The "automakers" until the recent advent of DI really didn't seem to give a crap about anything fuel related. Feel free to provide any evidence pre-1995/1990 for that. They did just fine offering fuel induction and carburetor cleaning services and would gladly mark up BG44 or whatever at the dealership level. But 1990 was a Seachange as some of the last carbureted vehicles became extinct (almost ironically Honda offered 1990 Accord with a carburetor LOL). The advent if emissions testing (I had tailpipe emissions tests in Virgina in the early 90's) made things moot.

The advent of more precise FI forced them to demand better fuels, or face class action lawsuits and yes gov't scrutiny at varying levels both state and federal. The move to Top Tier fuels are hardly due to the sole benevolence of auto-manufactures, and certainly began with the mandates starting in 1995 that were weakened in the 2000's. They knew/know they are under constant scrutiny even pre-Internet with the likes of Consumer Reports and even more so with the advent of car forums and automotive websites...
 
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