Reg versus Premium Fuel experiament in 09 PT Cruiser
in [Cars]
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From: Bill Putney on 4 Nov 2009 06:33 Ashton Crusher wrote: > I suppose we could split hairs over the quality of the lock washers > too. It is what it is and is what it was. Today's clearances are > much tighter, the engines are cleaner burning, etc. Sure, if you want > to take a complete system (today's engines) that was designed for > today's technology, and remove part of it and substitute parts it was > never designed to use, sure, you can make it worse. Next you be > singing the praises of wooden wagon wheels over modern tires because > the wooden ones never blew out from being run low on air. 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). :) -- Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')
From: jim on 4 Nov 2009 08:10 Ashton Crusher wrote: > > I suppose we could split hairs over the quality of the lock washers > too. It is what it is and is what it was. Today's clearances are > much tighter, the engines are cleaner burning, etc. 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. > Sure, if you want > to take a complete system (today's engines) that was designed for > today's technology, and remove part of it and substitute parts it was > never designed to use, sure, you can make it worse. 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. > Next you be > singing the praises of wooden wagon wheels over modern tires because > the wooden ones never blew out from being run low on air. 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
From: E. Meyer on 4 Nov 2009 12:01 On 11/3/09 11:37 PM, in article de42f5tottgaidulbacgamp3s6ppbe570c(a)4ax.com, "Ashton Crusher" <demi(a)moore.net> wrote: > On Tue, 03 Nov 2009 09:00:35 -0600, Don Stauffer > <stauffer(a)usfamily.net> wrote: > >> Ashton Crusher wrote: >>> On Mon, 02 Nov 2009 08:16:06 -0600, Don Stauffer >>> <stauffer(a)usfamily.net> wrote: >>> >>>> Ashton Crusher wrote: >>>>> I have pretty much gotten a decent feel for the gas mileage to expect >>>>> from my PT. The last three tanks averaged about 23 mpg. So when I >>>>> filled up yesterday I put premium in it instead of regular. It's too >>>>> early for a definitive answer but so far it looks like it's down 2 mpg >>>>> over what I'd been getting. About what I expected but I thought I'd >>>>> test it out. >>>> >>>> I had a Neon RT. I did an extensive milage test early on. I did ten >>>> tankfuls of regular, then ten of premium, figuring the variance of each >>>> set. The milage with premium was down a little, but less than one mpg. >>>> However, the variance in each set of runs was over 1.5 mpg, so I had >>>> to conclude it made no difference. >>>> >>>> I think the Neon engine was very similar to that in the PT (though mine >>>> had the DOHC heads). >>> >>> >>> My preliminary assessment is that it's down at least 2 mpg and >>> possibly as much as 3 or 4. >> >> >> That is a lot! How many tankfuls and what is the variance of the test? > > Just a few. But keep in mind that unlike having to run several full > tanks over similar but not identical courses, and then calculate the > overall mpg, I can get immediate readout from the computer in the car. > That's mainly what I'm looking at. I can run on the exact same street > at the exact same speed, resetting the computer at the start, and > immediately get the mpg results. Ditto on my "high speed" daily > commute. So it was immediately apparent that the mpg was down just > about as soon as I left the gas station after filling up. It's been > the same every day, whatever I was getting as "instant" mpg with > regular gas is down about 2 mpg now that it's burning premium. When > this tank runs out and I go back to regular if it goes back up it will > be just as immediately obvious. I'm looking at the trend, not > particularly an exact number. 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.
From: Ashton Crusher on 4 Nov 2009 20:30 On Wed, 04 Nov 2009 06:33:08 -0500, Bill Putney <bptn(a)kinez.net> wrote: >Ashton Crusher wrote: > >> I suppose we could split hairs over the quality of the lock washers >> too. It is what it is and is what it was. Today's clearances are >> much tighter, the engines are cleaner burning, etc. Sure, if you want >> to take a complete system (today's engines) that was designed for >> today's technology, and remove part of it and substitute parts it was >> never designed to use, sure, you can make it worse. Next you be >> singing the praises of wooden wagon wheels over modern tires because >> the wooden ones never blew out from being run low on air. > >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). :) 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".
From: Ashton Crusher on 4 Nov 2009 20:44
On Wed, 04 Nov 2009 07:10:10 -0600, jim <"sjedgingN0Sp"@m(a)mwt,net> wrote: > > >Ashton Crusher wrote: > >> >> I suppose we could split hairs over the quality of the lock washers >> too. It is what it is and is what it was. Today's clearances are >> much tighter, the engines are cleaner burning, etc. > >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. > you keep missing the point. > >> Sure, if you want >> to take a complete system (today's engines) that was designed for >> today's technology, and remove part of it and substitute parts it was >> never designed to use, sure, you can make it worse. > >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. > 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. >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. 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 http://www.youtube.com/watch?v=joMK1WZjP7g 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. > > They weren't over engineered. The basic block and heads were very similar to today's cars except that aluminum was rarely used. > > >> Next you be >> singing the praises of wooden wagon wheels over modern tires because >> the wooden ones never blew out from being run low on air. > >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: > I don't think I lost this one since I'm obviously right and you are living in a fantasy world. >"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 Sorry but you are wrong overall. |