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-   -   100 mile per gallon engine! (https://www.fuelly.com/forums/f8/100-mile-per-gallon-engine-5823.html)

GasSavers_rookie 08-18-2007 09:21 PM

Quote:

Originally Posted by CO ZX2 (Post 68816)
I just read the referenced article. David Vizard is a well respected performance writer among automotive journalists. With that said I continue......

I think he may be severely disillusioned when he implies he may be the only person with the knowledge required to drastically improve fuel mileage.

There are large numbers of GasSavers members and other FE sites that have demonstrated what can be done with ingenuity and hard work.

When I first became a member of GasSavers, I was in awe of members who had posted 70-90 mpg tanks. I had just reached my first ever 50+ mpg tank.

Currently my car, Old Reliable, is listed with 104.7 average mpg for the last 90 days. My last tank amounted to 107.3 mpg. AND I do not have the highest recorded tank on GasSavers. Antoine in his Smartan2 posted his most recent tank at 107.9 mpg along with other previous 100+ mpg tanks. MetroMPG recently posted a 104 mpg tank in his Firefly 2 Blackfly. And others are within striking distance. I am sure not all these tanks were accomplished at moped speeds.

What really gets me is that, of the three cars mentioned above, none have drastic engine modifications, if any at all. This is in direct conflict with what Mr. Vizard considers possible. He no doubt has considerable education and experience but it may be time for him to expand his horizons.

I'm curious; who do you know in the industry who has achieved 50 mpg in a carb. fed car under the varying conditions listed in the article with 1970?s technology?
I would love to study their work.

GasSavers_rookie 08-18-2007 09:25 PM

brucepick,
Please tell me where to post about thermal efficiency or among people who are willing to look at different approaches to automotive refinements.

ffvben 08-19-2007 07:49 AM

I'm not sure if this is true but back in the 50-60s someone came out with a carb that made 100mpg , it used fuel vapors. The big oil companies bought the inventors patent and quickly locked them away. but again I'm not sure on the facts on this, a teacher told me when i was in collage.

GasSavers_rookie 08-19-2007 08:06 AM

Quote:

Originally Posted by ffvben (Post 68916)
I'm not sure if this is true but back in the 50-60s someone came out with a carb that made 100mpg , it used fuel vapors. The big oil companies bought the inventors patent and quickly locked them away. but again I'm not sure on the facts on this, a teacher told me when i was in collage.

That is what this whole article was about, arguments both for and against the existence of such a carb.

GasSavers_rookie 08-19-2007 08:20 AM

Quote:

Originally Posted by theclencher (Post 68913)
Disproven for providing any sort of hp or efficiency gains. Basically, pick your stroke, ring package, and deck height, and find the rod that ties them together. End of story.

What are you, some sort of Vizard groupie?

Not true every thing being equal a short rod motor will accelerate better it shortens the time that the piston is at top dead center.
A long rod favors sustained upper rpm it lengthens the amount of time the piston is at top dead center.
Ask NASCAR engine builders why they use shorter rods on shorter tracks.
The differences may be small but so is the differance in winning and loosing.
I am a groupie of anyone who can back what he or she says.
Therefore, I guess that would make me a groupie of truth.
What do you stand for?

GasSavers_Rotareneg 08-19-2007 08:59 AM

The whole "100 mpg carburetor" thing makes as much sense as saying I've got a "100 mpg gas tank." It's the entire vehicle, including the driver, that matters. A 100+ mpg car that performs well is technically quite possible today, but it very likely wouldn't pass government safety and emmission stands and would be considered "ugly" by most consumers, be impractical to drive, and most importantly, cost quite a bit.

GasSavers_rookie 08-19-2007 10:29 AM

Quote:

Originally Posted by theclencher (Post 68922)
From a Hot Rod magazine forum (simply because my other links are not readily available to me at this time): "I remember reading about rod ratio in Grumpy Jenkins book about his 327s in Pro Stock in the 70's and back then he used custom length connecting rods just so he didn't go over a 1.7:1 ratio (when he was using GM steel cranks he was having rods custom made!). I also remember him stating that you really need to change the connecting rod length an inch to see any difference.

Darin Morgan at Reher Morrison swears up and down that it makes NO measurable difference between a 1.59:1 to 1.91:1 in a 9000 RPM small block chevy. Yet Nextel Cup today is around 1.9:1 and I'm sure about every F1 engine is over 2.0:1 and NHRA Pro Stock is around 1.7:1 Why? Who knows, but many people much smarter than myself have stated that it is all about packaging constraints rather than searching for a certain rod ratio. As far as I know, there is more of a gain going with a lighter and more stable piston with a well spaced ring pack than pushing the rod too far up into the piston just to get a higher rod ratio.

Here is a direct quote from Darin Morgan (head of R&D at Reher Morrison)

Quote:
"Just about everyone I know is brought up to believe this [that R/S significantly effects power]. The GM engineers believed it too until we proved it to be false. In 1995 Reher Morrison conducted an R&D project funded by General Motors to once and for all prove the rod ratio theories that everyone subscribes to. In a tall deck small block Chevy the rod length was changed from 5.550 to 6.650. The difference in ratio was 1.59 to 1.91. The difference in power? NOTHING, not one single horse power difference. The dyno sheets looked identical in every way all the way up to 9000rpm. That is why I now say its a fallacy.

Now, I once again want to clarify my point on rod ratio so nothing I said is taken out of context. The test we did was from 1.59 to 1.9:1. I never stated that above or below those points that there may or may not be demons lurking. From what I have seen with the older 265 engines with ratios in the 2.15:1 range and the extreme 500+cubic inch small blocks in the 1.3:1 range I can safely say that there are problems with induction system lag above 1.9:1 and frictional power losses, parts damage and decreased component life below 1.5:1. Evaluating the differences in power output from 1.3:1 to 2.15:1 would be impossible because of all the other variables that must be changed in order to achieve that task. I think its a moot point any way because in each case they used what they had to as far as block and deck height as is the case today. We now have the Aurora block with 8.200 decks so we don't have to put up with 2.15:1 rod ratios. What I am trying to get across, is that trying to build an engine around an "ideal rod ratio" is a losing proposition. Design the piston with the ring package properly compacted and spaced , put the pin as high as possible so as to not intrude on the oil ring groove, and connect it to the crank what ever stroke that may be. The rod is dictated by the piston design, stroke and deck height not a preconceived "ideal " rod ratio.

Before you blast me with obscure engine combinations I must say, NO I am not condoning sticking a 4.750 stroke in a 9.8 deck block with a 1.2 compression height piston. A little mechanical common sense has to come into play here as well."

I was all hung up on rod ratios after reading Vizard and Yunick but then I found data from Hot Rod magazine build-up articles, Reher-Morrison articles, I think an Engine Masters Shoot Out, an engine builder that works in NASCAR, etc. that debunked that theory.

Of course a websearch will find tons of info both pro and con. It depends on who you find to be the most credible.

You think you're a groupie of the truth, and so do I. Are you prepared to back it up?

Study all things so that you will know the truth and the truth will set you free.
Being born and raised in the Dallas area I am well aware of Reher Morrison Racing I have done business with them in the past.
I also know a considerable number of people who have had to change the combo that they received from them in order to be competitive.
This was not the case years ago. Money changes every thing.
The shop that does my machine work and dyno?s my engines has personally had to rework several of their combos do to lack of power or catastrophic engine failer.
A local track record holder used them for short blocks but had to do his own heads and spec his own cams because what they where doing was nowhere close to the power or power range he needed.
He has recently had to take his work elsewhere.
I do not personally know Darin but I was told two days ago, he would be leaving for untold reasons; he is well respected, but not allowed to do what he is capable of is what was said.
You have to ask your self why they have not been competitive in prostock for years.
Hot Rod Mag. and Reher Morrison have become parts pushers, the R&D for GM was 12 years ago.
The person in question that started all this hoopla still does R&D for most of the major Auto manufactures, Cylinder head, Intake, Cam companies. That?s saying something.
So as far as credibility goes, I guess you have to judge for your self.
As for Grumpy, you only have to watch Nhra to see he builds some of the most competitive engines in the field.
Smoky Yunicks work goes with out saying, I shudder to think about what he would have done if he was not so set on pissing people off.
Not only Smoky but all of us in this field or any field could benefit from looking at the good in what people have done instead of trying to find something to stab them with.

trebuchet03 08-21-2007 10:06 AM

Quote:

Originally Posted by rookie (Post 68935)
The person in question that started all this hoopla still does R&D for most of the major Auto manufactures, Cylinder head, Intake, Cam companies. That?s saying something.

No... Really, it's not. The person is still afflicted by the same capacity of making a mistake or a bad call, just like everyone else is.

Just keep in mind that when these major auto/defense/contractor manufacturers make a "mistake" - it's not called a mistake. They call it an anomaly or some derivative thereof. Feel free to trust me, or not - but these "anomalies" happen more often than one would hope :/

------
As for the point on thermal efficiency... Yes, TE will be the ultimate cap. But many people here have proven that:
Quote:

OK - by now I should have convinced you that 98% at least of any mileage improvements will come mostly from engine development and maybe a little extra from fuels.
really is not true even though I'm not quite sure what "98% at least of any mileage improvements" is a reference to o.0 100% of my mileage increases have come from driving technique and perhaps some aero shenanigans ;)

I am also drawn to the 70/80's claim from Luigi Colani of a 50% FE gain on semi trucks only VIA aerodynamic modification. Even though trucks are decent on efficiency to begin with (when hauling).

Another thing comes to mind too... The Opel eco-speedster which averaged, over a 24 hour test, 140mph getting 113mpg. Personally, I have no problem with 155mph top speed, really - the average commuter car will live between 0 and 80mph ;) Small frontal area, light weight, aero design, small engine (1.3l diesel).

Whenever someone asks for money for a claim they have not yet prototyped... I run away. Unless they're asking for VC money - which is a different story. But if they're asking, they better be saying wtf. it is they're doing first. If he's trying to create an engine that runs at 1200F reliably, great - I'd back a claim for FE gain (perhaps not to the extent he is, but shoot for the stars ;) ). I mean, really - we already have the materials tech for such high operating temps :p

------
My last point.... I think "98% at least", of all mileage improvements will be switching away from petrol based fuels (note my lack of time frame) ;) I got to ride in a vehicle that got 170mpg equivalent and did 0-60 in 3.07 seconds this past summer (it was a modified ariel atom). That beats the 160mpg claim in that article :p

itjstagame 08-21-2007 11:48 AM

Interesting article, it's odd that he goes on and on about how fuel delivery is not the problem. He's hinting at the fact that he's vaporizing the fuel better and a carberator cannot meter vapor (neither can an injector), so he's changing the delivery.

The way his article reads it sounds to me like he's hinting at doing something similar to these:
https://fueleconomytips.com/2005/12/0...gallon-of-gas/
https://www.fuelvaporcar.com/index.html
https://fueleconomytips.com/2006/12/0...2%80%99s-tale/

The issue is in dealing with leanburn, if he's changing the engine to handle that somehow, that's fine but I don't think any of these article's increase the thermal efficiency of the engine itself, they may increase the efficiency of the fuel because it is no longer being used as cooling and and is being metered more closely to have more of it's energy go to motive force.

I would like to try some of that but it's more mods than I can deal with although I have thought that cannibalizing the old K-jetronic fuel distributor on my Audi would make a good way to inject water.

Sludgy 08-21-2007 12:55 PM

There is no way that a 4, 6 or 8 cylinder car is ever going to get 100 mpg at normal (55-65 mph) highway speeds.

A 100 mpg car is possible, but its engine has to be running at its most efficient point: WOT, and while at the best efficincy rpm while at highway speed. 1.5 to 2 liter 4 cylinder engines make way too much power to run at WOT an efficient rpms. Smaller 4 cylinder engines, like the Japanese "liter car" class operate at WOT at about this rpm, but cylinders are too small to be efficient. (The smaller the individual cylinder, the less efficient it is. Really small cylinders like 50 cc scooter motors are only about 20% effient, but big 12" bore diesels are about 40%)

The solution is to use fewer, larger cylinders.

SO, Here's the recipe for a 100 mpg car engine:

1 cylinder, long stroke, 400 to 800 cc displacement, with all the goodies: four valves, direct injection / lean burn and tuned intake and exhaust. Of course, the usual aero body and LRR tricks would be needed.

So what do you get?

https://www.seriouswheels.com/cars/to...-liter-car.htm


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