Mike Ward

For anybody that wants to believe in valve recession/seat erosion/SLAMMED or HAMMERED/sky is falling stuff due to lack of lead here you go:

http://forums.corvetteforum.com/c1-a...ubstitute.html

Maybe you can pull their legs for a while.

Paul Workman

Honestly, I don't know what you're talking about! Up here in "corn country", we've had ethanol in fuels since the late 80s/ early 90s. It did result in me having to replace my injectors to some not suseptible to being dissolved by the alcohol, and it does result in less mileage per gallon, and no I'm not in favor of it's use (or worse, the upping of the percentage to 15% as the corn lobbiest are pushing for). But! Far as any/everything else in your rant, if everything was going to hell as fast as you seem to imply, there would have been such an outrage by now; some 25 years hence.

Furthermore, water is absorbed by alcohol, expecially methanol, and remains in susupension like water in a sponge, i.e., it does not ordinarily precipitate out to collect in the bottom.

I'm not saying you don't see water in the bottom of your fuel tanks, or that you don't have rust, or the like. But, I don't think the ethanol is the culprit here.

I have quite a bit of experience with water tight enclosures exposed to the atmosphere. And, from years of experience, I can assure you that if humid air is allowed to be drawn inside an enclosure (as the enclousure cools and the air within contracts to form a partial vacuum) and then the enclosure continues to cool (as in after dark!), the water vapor WILL condense on the sides of the container and then and collect at the bottom of the enclosure. (LOTS of water - especially near the coast or on board ship!)

The fact that you live in MS is a factor in what you're experiencing. Humidity averages higher in gulf states than it does in some places. It leads me to think that perhaps water in the bottom of the tanks is more likely a result of condesation, and nothing to do with 10% alcohol in the fuel - or at least not the water settling to the bottom of the tank. (Alcohol will only hold so much. So, like a sponge any additional water is not absorbed and the heavier water sinks to the bottom of the container.)

I might be "all wet", here, but I don't think the ethanol is the villan here, and even if removed from the fuel, I don't believe your problem will go away. In fact, because of the capacity of alcohol to abosorb water, it will actually prevent some water from collecting in the bottom of the tank. (Up in cold country, mostly before there was some alcohol in the fuel, everybody had a can of HEAT or two handy to keep gas lines water in gas lines from freezing. HEAT, was essentially methanol (wood alcohol) that really likes to soak up water! A can of HEAT with a fill-up, especially if the vehicle was going to sit for a few days, was pretty commonly done. This kept water from precipitating to the bottom of the tank and fuel lines where it would freeze. But, one hears about HEAT a lot less than before. Now days there is ethanol in the fuels, and it may be a coinsidense, but frozen fuel lines isn't something we hear about all that often anymore over breakfast at the local cafe.

Except for that 10% that keeps my tank and fuel lines (especially) from freezing up, I'm not a fan of alcohol. The "Greenies" don't realize it takes more energy to produce a gallon of ethanol than the ethanol produces when burned, and that energy to produce the alcohol is electricity, usually made from coal burning plants!! So, where the hell is the CO2 reduction these idots are always harping about???

Seal the tank if possible, and keep it full as possible otherwise. Your water problems will "vaporize", I'm sure!

P.

noonie

That's the most common result. For various reasons, when the saturation point is reached, water sits in the bottom of the tank at the pickup point to be ingested by the fuel pump instead of gas. Adding products like Heet these days does more harm than good.
A good petcock in the bottom of tanks could work wonders.

mrvette

Tim, that exactly my point, the removed the admitted cheep solution of Lead in the gas, so that increases prices, then we put in alky to kill MPG, and in this conversion process we consume more crude oil over the last 40 years now, and the only savior at all was electronics, and so with electronics, we COULD be running much better with cheaper gasolines by eliminating alky and reducing costs by going back to TEL....

I don't know how many attempts to say it, but that's my basic position all along....the public is being raped over by all the bullcrap lies the weenies have propagated over the years, to the point most folks just accept the BS, I never have and never will, because I been working/reworking on cars for 1/2 a century or better....
closer to 60 years now, IB 68 here in another couple of months, started lawnmower stuff around age 8, graduated to cars when some older kids showed up with hotrods in the hood....

Mexican Bob

You're welcomed to believe whatever it is that you believe and site whatever source supports your beliefs. I prefer to site sources that designed the cylinder heads and they agree that hardened exhaust valve seats are a method used to prevent VSR (valve seat recession) in "leaded fuel" engines. However, since you know everything and insult anyone with a differing opinion, there is no point in telling you a thing. Hopefully, you won't continue to propagate the myth. There are countless sites that support my argument, including GM, Ford and Mopar and factory supported racing teams and engine builders.

While it is an unlikely thing in low-mileage show cars and others that are rarely driven "hard" or for extended use (more than a weekend here and there), it is no myth that valve seat recession for heads without induction hardened seats were subjected to a constant beating by the valve.

Since you seem so bent on distorting reality to your own perception and will use any method to support it including trying to make fun of my word choices, consider the valve spring pressure with the valve opened and on the seat. Add to the opening/closing cycles the ramp rates of common camshaft lobes typical of the kinds of cams people are putting in their engines. Wait for the tappet to hit the flat of the lobe and measure how much your valve bounces on its seat before it closes completely. Do this repeatedly at 5500 RPM or more. The idea that a typical stainless steel valve literally hammers the crap out of the valve seat at dual coil spring forces shouldn't be so difficult to grasp, even for someone who already knows everything.

Did you weigh your valve-side of the rocker arm components and calculate the forces involved at the lobe lift multiplied by your rocker arm ratio?

Does anything get through to you?

How about a report provided by the US Department of Energy and performed under contract by the National Inst. for Petroleum and Energy Research that summarizes:

"Results show the higher speed engines experienced valve seat recession using unleaded fuel while lower speed engines did not show valve recession using the unleaded fuel. No valve seat recession occurred using the 1.1 gm/gas leaded fuel. The use of .10 gm/gal lead reduced valve seat recession compared to unleaded fuel, but did not eliminate recession in all cases."

There is probably a huge conspiracy between the US Dept of Energy and the National Inst. for Petroleum and Energy Research to pull everyone's legs about valve seat recession and leaded/unleaded fuel just so that you can be right all of the time.

Many GM engines are not as vulnerable to this as other engines from other manufacturers for a variety of reasons. Two of the biggest reasons are the lowering of static compression ratios and induction hardening (heat treating) of cylinder heads. Both of these occurred before unleaded fuel was mandated in the USA. It isn't as if GM engines, and specifically "Corvettes" are "immune" to the problem, particularly if not properly considered by a rebuilder seeking to make more power using factory heads but common add-ons such as roller camshafts and related valve train parts such as stainless steel valves and high tension springs.

This isn't for your benefit, because you obviously will never learn a thing from someone like me. However, it is for those who may read it and choose to consider rational discussions versus exaggerated claims and siting questionable sources...while insulting those who disagree with you.

Is the problem largely mitigated by GM cars that rarely see much use? Do you have any real data that describes those engine builds that represent pre-unleaded owners, their usage patterns and/or modifications they've made that could negate the issue such as installing hardened seats in their heads? Even taking a group of 10 or 20 Corvette owners and asking them if they've ever had any problems running unleaded fuel is subjective at best and does nothing to prove that it "can't happen to Corvettes" as you suggest. If you do a responsible sampling of data from those owners, how many have factory stock engines? How many use the vehicle in a manner consistent with driving patterns that would have a reasonable likelihood of encountering VSR? Since you contend that it doesn't exist and/or is a mythical beast that only occurs in taxis and other "heavy use" vehicles, you don't have any supporting data and you're not looking for it. Your head-in-the-sand ostrich methodology isn't responsible. Like mrvette, I lived through the period and the problem wasn't "invented" by those who needed more work at the local machine shop.

I've seen stacks and stacks of cylinder heads from all manufacturers (well, GM/Ford/Chrysler) that were waiting for new seats to be installed. I asked the machinist why there were so many of them. This was about 1977 or 1978 and he told me that it was "the damn unleaded gas." Pardon me if I have considerable more respect for that old guy who knew a trade that few today know or practice...than some wannabe who couldn't tell a valve seat from a tree frog...but is ready to fight to the death over how the rest of us are causing the destruction of the world. The real destruction of the world comes from the spew-fest of misinformation being presented as fact by the uninformed, misguided and "income redistributors" who believe that the ethanol tax is better for the environment. Of course, a good, die-hard flaming liberal never lets facts get in the way of their causes:

"These data have been assembled into The Clean Fuels Report comparison of fuel emissions and show that ethanol exhaust generates 2.14 times as much ozone as does gasoline exhaust. When this is added into the custom Localised Pollution Index (LPI) of The Clean Fuels Report the local pollution (pollution that contributes to smog) is 1.7 on a scale where gasoline is 1.0 and higher numbers signify greater pollution."

Now don't go running around and bumping your head on the truth...it could leave a serious dent! The tax contributes to the creation of ozone and they're talking about RAISING the percentage of ethanol in motor fuels...for what? In order to prove they're right about "greenhouse gases?" Talk about a festering disease...ever wonder how much CO2 evaporates out of the ocean every day? Silly liberals think that they can really control it? No...they just want to get rich off of it and will do anything they can to ram it down our throats...including telling us we're wrong when we're right and then acting like we're bonkers for ever suggesting such a thing could be true. Unfortunately, a lot of bleeding hearts believe such nonsense and trumpet their ideological causes as if it is real science.

Fine, valve seat "erosion" doesn't exist. And I know. I was there when I didn't see it.


MxB

Solid LT1

#1 reason right there now maybe our vintage Vettes will no longer suffer the slow poisoning of their fuel systems. This stuff is CAUSTIC to our fuel tanks/lines/carburetors.

Mike Ward

So- got any pictures of C1/C2/C3 Corvette cylinder heads that suffered valve seat recession? Like many others you talk a great story (lengthy at that) and are wonderful at theory. Show us proof. You claimed to have countless sources that prove it- let's see.

noonie

Here in Florida, it's the law that only e10 can be sold for road use. Some exemptions like racing, motorcycles, marine antiques (which c3s have always qualified for anyway). Problem is, station owners don't sell a lot of non ethanol, so it's not feasible to stock it, so it's hard to find.

Will be interesting to see how this shakes out with the state law. It could go the other way and the price drastically increases if the corn prices rise because of the lack of subsidy.

Mexican Bob

Are photos the only proof you'll accept? I know a guy who is 76 years old who raced 'vettes for a good long time. Let me ask him if he ever had any problem with the seats in Corvettes due to unleaded fuel. He's ran a full-service automotive machine shop since he was a young man. If it happened, he's probably seen it. I don't need any more proof than that. And, if he says that he never saw it happen to Corvettes, I'll be happy to say so right here, too. I don't want to be wrong about things, but I'm not too big to admit it when I am or too proud to think I already know everything about it, which I don't.


MxB

694speed350

The reason for that was the cats that was used to lower emissions if you ever drove behind one of the cat cars back then you will remember the sulphur smell. the compression was dropped to keep pre-ignition to a minium. exhaust gas recirculation was brought in to lower combustion temps. Thanks epa for nothing. like you said though the way of rating octaine did change. In the states todays 93 octaine is inferior due to the 10% alachol added We old fogies like me and mrvette long for the days when we could run 12/14/1 compression and advanced timing. no cats and no computers.

Mike Ward

I had presumed that you were speaking from first person experience, not relaying on third handed info.

I've played with cars, bikes, snowmobiles etc since the early 60s. Valve seat recession was a big deal on some cars and many bikes. Never on Corvettes. They don't run hot enough for long enough to create the specific conditions required for seat erosion. An Olds Vista Cruiser pulling an Airstream over the Rockies in August is a different case.

Mike Ward

So go out and buy street legal 105-100 octane. What's stopping any of you guys?

couperdecar

105 octane fuel !!! ? How about availability? You are talking about something that doesn't exist. Its a myth.

birdsmith

These are FACTS. Chevrolet began induction-hardening their valve seats in 1971 as a response to the introduction of low-lead (and eventually no-lead) gasoline and the anticipated valve seat recession that would occurr as a result of the removal of TEL. General Motors has a reputation for pinching pennies and you can pretty safely hedge that they wouldn't have spent the money to add this operation to their production process unless they really felt it was necessary. It is also a fact that car manufacturers began dropping compression ratios in 1971 in order to preclude detonation problems that would result from the reduced octane in caused by lowering the lead levels in motor fuel. True, the method for rating octane is different today BUT the maximum commercialy available octane available for purchase today is markedly less that that which could be purchased at ANY gas station in 1970. Musclecars that were for sale to the general public then had compression ratios as high as 11:1 with heat-retaining iron heads and crude carburetion systems. Today 10:1 is about the maximum for any production car, and that with heat-dissipating aluminum heads and highly sophisticated electronic ignition and fuel injection systems. It is also true that tetraethyl lead is pretty toxic stuff and I suspect that our overall quality of life has probably been slightly improved by its removal from commercial motor fuel, but nonetheless I still love running it in my race car whnever I'm at a track day- it smells absolutely magnificent. As for the ethanol issue, if it really did add to the viabilty of America's energy supply I would personally be for it, but the thing that I observed upon its intrduction into our fuel back in the 90's was that my mileage was being reduced in direct relationship to its percentage, i.e., E10 produced a near 10% reduction in mileage over straight gasoline, and it literally takes more energy to produce it than it has in it! How in the hell is that in any way of any benefit whatsoever?? The obvious answer is it's NOT and the reasons for it being shoved down the throat of America's motoring public are purely political. It is also a national security issue because we are using energy to produce a motor fuel that we could be using AS the fuel itself, making us more dependent on foreign supplies. THERE, I said it!

Mike Ward

Please go argue with Sunoco

http://www.racegas.com/fuel/index

birdsmith

Mike, with the exception of the first one on the list (which was 100 octane) none of the fuels shown on that list were street legal ANYWHERE, i.e., you can't legally pump it directly into your car. There is virtually no limit to the different types of racing gas that are available but unless I missed something, was specific to street-legal pump gas. BTW, how much does that Sunoco cost?? $10/gallon??

Mike Ward

Yes true- I was referring to the 100 octane street legal gas. I meant to say 95-100 street legal in my post above, not 105-100.

There's very few street driven cars that actually need or run at their optimum on anything over 93 so the price and availability is a moot point at least for me.