Reg versus Premium Fuel experiament in 09 PT Cruiser

The wagon wheels with metal treads have an order of magnitude less rolling resistance too - so better fuel mileage, but of course their traction (cornering, accelerating, braking) sucks. Sounds like a gubmint solution to some serious problems - something Al Gore and Obama might be interested in having legislated (except, of course, Congressmen and Senators would be exempt from having to use them). :)

Reply to
Bill Putney
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But that is a result entirely of the electronic improvements. It is not as if the tighter clearances couldn't have been achieved in the 60's. But if you have an engine that is producing internal carbon deposits tight clearances can be fatal to engine life. It is not as if those clearances used then were not there by design. It was possible to make engines with tighter clearances in the 60's but tests showed that brought with it a bunch of reliability problems.

I suggest only substituting the parts that were really making the difference to illustrate a point. Conversely you could take an engine from the 60's and put a modern fuel and ignition system and if done right it would eliminate the ring and valve problems that you claim are inherent from a weak engine design.

What is different today is the engine management system and manufacturing management systems. One of the results of all that is cheaper materials go into building a car. For instance, in a car there is a lot less metal all around. That extra metal that used to be in cars

40-50 years ago was not making the car weaker as you claim. The simple fact is that an engine of the 60's could be expected to spend a considerable amount of its life running with the timing off the mark and the fuel mixture out of balance and an unpredictable amount of carbon in the cylinders. In order to make an engine last under those variable conditions it had to be over-engineered. That over-engineering disappeared as the electronics got better and better.

Don't try to change to a different argument because you think you lost this one. I was disputing your incorrect assertion about engine design:

"Up until the mid/late sixties, engines were so weak that it was common for them to need valve jobs before 100K and for many of them they needed both rings and valves before that point."

The cause of valve and ring problems of which you speak can be entirely attributed to the fuel and ignition management used back then. Back then, an engine that was meticulously kept in tune lasted much much longer than 100k. But most engines weren't.

-jim

Reply to
jim

That might be your problem. The immediate readout on most cars is based on throttle position and not on actual fuel metering. If there is a way to reset the display to defaults and let it relearn, try that. To really know, you need to get out the old paper & pencil and calculate it over a few tanks of gas.

Reply to
E. Meyer

Be careful what you say. If Gore overhears you he'll want to mandate that we all switch to nitrogen filled tires with heavy fines for using "air".

Reply to
Ashton Crusher

you keep missing the point.

No it wouldn't. If you used the original factory rings and non-hardened valve seats and all the other factory parts of the day you would continue to expect early burning of valves and early wear out of the rings.

The keep talking about how if you CHANGE things on the old engines you can make them better. Well DUH. And how if you CHANGE things on new engines you can make them worse. DUH again.

Now you have wandered off into the entirety of the car rather then the engine. But if you want to see how far off the mark you are go watch this crash test of a big ol heavy full of metal 59 bel aire against a much smaller cheaply made modern car

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The simple

They weren't over engineered. The basic block and heads were very similar to today's cars except that aluminum was rarely used.

I don't think I lost this one since I'm obviously right and you are living in a fantasy world.

Sorry but you are wrong overall.

Reply to
Ashton Crusher

I've already done that and the readout is very close to the total tank average. And as I said, my main comparison is steady state driving, constant speed, on the same road with the two different gas's. It will give an accurate relative difference between the two gas's but both might be 0.4 mpg low (or high). The last tank pen and pencil average was 25 mpg whereas the computer said 24.6.

Reply to
Ashton Crusher

Hmm - what if we mandated that you had to fill all tires with CO2. Gore could have an exclusive franchise on the special equipment that would be required at every filling station and tire servicing facility in the country that would separate out CO2 from the ambient air for people to use to inflate and top off their tires. That way we could starve the earth and those pesky plants from that awful CO2, and an entire industry (owned and controlled by Gore, and taxed by the gubmint) would be created - a new job stimulus program that would shuffle money around and accomplish nothing like everything else they are trying to do - another entire false economy built on the "merchant's broken window" principle.

This should be made part of cap and trade - OH - I'm sorry! I forgot the new euphemism for that is the "Clean Energy and Security Act".

Reply to
Bill Putney

Also left out of the discussion is the fact the the VERY BEST motor oil you could buy in the late 60's wouldn't qualify as chainsaw bar oil today. Lubricants have come WAY further than engine design- at least in terms of bearings, rings, and other "hard" parts. Fuel managment systems have come as far as the oils or even further. If you could find a "pickled" (preserved, never run) factory engine from 1965 and put it into use with today's synthetic oils

Reply to
Steve

Stupid "send" button ;-)

If you put it into use with today's synthetic oils, you'd find that it runs as long or maybe longer than anything modern. If my '66 engine went

180,000 miles with the kind of "group 1 or less" oils it had early in its life, imagine how well it would do with group IV synthetics right out of the box.
Reply to
Steve

No. They're not. Bearing, ring gap, and piston-to-bore clearance specs on my '1966 and 2005 engines are virtually identical.

THAT is true, but has nothing to do with "strength." That's airflow design (manifolding, heads, chambers, valves) and fuel management (EFI instead of carburetors).

Reply to
Steve

The PT used the 2.4 DOHC engine as the base version, the turbo 2.4 DOHC was the option. Same engines as the biggest Neon option. The Neon came variously with the 2.0 SOHC, 2.0 DOHC, 2.4 DOHC, and 2.4 DOHC turbo.

Reply to
Steve

It would fail in short order without good old tetraethyl lead in the fuel; no hardened valve seats in an engine from that era.

Reply to
Matthew Russotto

That turned out to be a very overstated problem; the valve seats would last a long time without lead. OK, a valve job would be needed long before anything else on the engine needed replacement, but that would still be after many miles.

Reply to
Joe Pfeiffer

I'm not so sure about that. it seems that such wear isn't as bad as was once believed.

Reply to
Brent

That isn't true. There was a lot of concern about that at the time of the switch over from leaded to unleaded. But just like the Y2K scare that problem never seemed to materialize. I know a guy who put 300K on a '49 willies jeep after lead was phased out without any valve or ring problems and no increase in oil consumption. I myself ran a '66 chevy

283 for 20 years after lead was gone and didn't have any valve problems. The real issue was lead was a lot cheaper way to boost octane than any thing else. The scare tactic was just to keep lead in gasoline as long as possible and it worked. If the problem had been truthfully posed as do we continue to spew lead across the country only to benefit the oil companies, then it would have been eliminated 20 years earlier. the exact same thing can be said of MTBE.

-jim

Reply to
jim

Hey, Stellite!. Stelliiite!! *

*with apologies to Tennessee Williams
Reply to
Heron McKeister

In fairness, Y2K was a huge problem, but it was seen coming just barely far enough away that companies were able to put a huge amount of effort in and fix (or band-aid) their code so that almost nobody outside was inconvenienced. Had the work not gone into fixing it, the dire predictions would have come true.

Likewise my impression remains that the concerns about valve life were real, and not just oil company propaganda. But while the concerns were real, they turned out to be unfounded.

Reply to
Joe Pfeiffer

Both my '65 Corvairs do, stock.

Reply to
AMuzi

Effective propaganda may produce real concerns. But consider the facts - It was well known that lead was a poison when it was first added to gas in 1920. and it was well known that lead is a substance that never biodegrades when it is placed into the environment. It turned out that there were considerable financial advantages to the automakers and oil companies but hardly a shred of true evidence there was any advantage to the consumer or driver of cars. Yet most people had been convinced it did have advantages. But your right this wasn't oil company propaganda The serious lying came from the auto manufacturers.

The lead in gasoline got there by agreement between Congress, auto makers and oil refiners. The automakers wanted higher octane fuel the oil companies didn't want to bear the large expense of the extra processing to make high octane fuel. Back then it would have more than doubled the cost. The deal they arrived at was simple. Put lead in the gas. To sell this to the public the automakers would claim that their cars would fall apart without lead and congress and the oil companies would go about selling the public on the health benefits of lead in gasoline.

The main reason that the automakers made a big deal out of coming out with newly designed valves and other components when unleaded fuel was first started to be sold in the 70's was that they had claimed 50 years prior that they had a mountain of scientific evidence that bad things would happen to engines without lead. They couldn't now just ignore those claims they had stated as scientific fact. Modern studies have revealed that those early studies were probably complete frauds. One 2003 study showed that adding Tetra ethyl lead to gasoline reduces engine life by 50%. The current extended spark plug change intervals are really almost entirely due to the removal of lead from gasoline. Typically spark plugs electrodes and insulators erode 4 times as fast when using leaded gasoline.

One interesting side note is the role ethanol played in this. Initially the oil companies rejected the idea of creating higher octane fuel by adding a well known poison to their fuel and told the automakers to take a hike and they didn't give a damn about octane that was the automakers problem not theirs. After all why should they compromise the image of their product for the benefit of the automakers. So automakers (mostly ford & GM) started fooling around with mixing ethanol as a fuel. That got the oil companies attention and suddenly the oil companies saw the light and started supporting the lead additive. Ethanol as a fuel disappeared for quite a while. It took 80 years and 7 million tons of lead blown out the tail pipes of cars but eventually ethanol made a come back.

-jim

Reply to
jim

No, there were _major_ advantages to ethyl. It not only made high octane gas much cheaper to make, it made high octane gas _practical_ to make. Yeah, it's possible to make 90 octane gas from casing head, but it evaporates right from your tank and it's substantially less safe to transport.

Higher octane gas means higher performance engines for the consumer, and the consumer demanded that.

A side effect was the fact that valve seats lasted a whole lot longer because of the lubrication the lead provided.

And yes, everybody knew lead was toxic, but I don't think anyone had any notion just how toxic it was. Remember only 20 years before, lead acetate was a common ingredient in cakes and candies. On top of that, nobody had any idea that the auto industry would explode to the point where emissions were a big issue.

In retrospect, it turned out to be a bad idea, but I don't think you can blame folks at the time. For a while, you could buy gas with and without ethyl; they coexisted in the marketplace. But as I said, it's just not practical to make high octane gas without an octane enhancer. And the first convenient one that was found was lead.

I'd like to see a cite to that 2003 study. I'd also be curious if that study used an engine with modern hardened valve seats or typical 1960s soft seats.

Again, I have seen plenty of ads from the thirties promoting ethyl in gas, but I have never seen any of them promoting ethanol in gas. I'm not sure anyone ever knew about it in the general public.

Ethanol didn't make a comeback, though, until after lead was replaced by MTBE, and then MTBE turned out to be even worse than lead was.

--scott

Reply to
Scott Dorsey

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