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Old 01-16-2020, 08:44 AM   #10 (permalink)
Ecky
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I'll give some thoughts on some other points in that case! Some will be opinion, some speculation.

Quote:
Originally Posted by bradlington View Post
One has to ask why the early vehicles had gear shift timing that was adjustable by the driver on the fly .Same principle was used with aircraft - boost and cruise control.

I personally like to have more control over variables; it's why I have an aftermarket ECU. If I were to take a guess at this, it's probably some combination of 1) Drivers can now basically control shift points entirely with the go pedal. Press it harder and the shift point moves higher, prioritizing acceleration. Also, 2) Most people either don't touch these things, or set them to very suboptimal settings. Engineers are pretty sure they're smarter than the average driver now, and have no issue with taking some things out of drivers' hands.

Quote:
Originally Posted by bradlington View Post
The same principle has been used by some innovators tinkering with vapor and other methods to adjust by fuzzy human logic for efficiency .
The vacuum negative feedback resulted in being able to drive without the driver having to manually adjust - this made sense for demand but lead to the decades of cloak and dagger by manufacturers on how they do things and why.

This made a lot of sense when systems were very basic/primitive, but for a long time cars did not have DFCO either - something vapor systems do not allow. ECUs can now call for the delivery of fuel as-needed, sometimes following very closely to how carbs did and other times very differently - as needed.

Quote:
Originally Posted by bradlington View Post
I have one shortfall in that my vehicle is 1999 /2000 - sold as 2001 but the ECU is a closed shop in terms of people that have truly reverse engineered it . Over and above this the ECU does not spit out mpg in real time so my notes ,recordings and long term notes would not satisfy any scrutiny .

On a 1999/2000 you could add an OBD II device like a Scan Gauge or UltraGauge. The forum is actually having a give-away for one of these right now. They do a pretty good job of approximating fuel.

If you want to get something more exact, you can pick up the parts to assemble an MPGuino very easily, which can count the fuel going through your injectors and is far more accurate when AFR varies, often coming to within 1%. I have one in my car and love it! It won't however, be able to account for fuel you're side-loading, such as with your vapor system or HHO. You would need to manually calculate fuel added this way and add that to your usage/expenses.


Quote:
Originally Posted by bradlington View Post
Here is what I think and only my interpretation and limited understanding :
Long term aims to move the industry away from the user ,home experimenter from gaining 100 knowledge of the inner workings of any ECU design .

Agreed. I believe it's actually federally illegal in the US to crack or replace an ECU in most cases, because it's "tampering with emissions systems". I can understand and appreciate emissions laws here (pollution and smog have improved dramatically in the last 40 years) while at the same time still bristling at a lack of my ability to change things.


Quote:
Originally Posted by bradlington View Post
Having said this going to Fuel injection and then direct injection showed that the industry was in a race to get the beneficial acceleration scores closer to public demand .

Going back to the manual timing and vapor - there is some lag in the sense that good vapor systems that are not pressurized for high speed delivery can have as an inherent part of the system .Slow acceleration and manual air control together with the vapor is key .
Looking at history ,the era when vapor carbs were becoming successful in delivery outstanding mpg figures, the change happened to follow the fuel injection design and OBD world adoption .

I've seen some vehicles with carbs that have some pretty good efficiency in narrow areas of the map, but it's hard for carbs to deliver the best of both worlds like electronic control can. With ECUs, there really isn't a whole lot left on the table in terms of tuning and improvement, unless you want to make some intentional sacrifices, such as increased pollution or engine longevity. There's no guesswork with it anymore.


Quote:
Originally Posted by bradlington View Post
As far as mods go I can list them but they are for interest and I will not support any tech results or fugures. All I can say is never ending and ongoing projects .
List of my changes :
Exhaust -replaced original to free flow with Cowley straight through .
Cat delete-
HHO - hho supply to Throttle body intake controlled by manual PWM control . I am using KOH (Potassium Hydroxide as electrolyte)
AFR-On-board addition wide band O2 sensor for monitoring real time driving AFR .
Manifold Pressure gauge- for on-board driver monitoring.
Efie- Manual dual control for manifold offset
Fuel Heat exchange-My own design have not seen before on internet.This innovation is neater than the old school radiator or exhaust copper pipe versions .
PCV delete- Not common on boxer engines - filtered ports.
IAT -Internal air temp -Manual switch and offset adjustment .

Changes used already and to be added in near short term :
Water ultrasonic vaporizer
Fuel vaporizer - new design for heat cracking being made before adding .

I recently read a peer-reviewed article showing positive benefits from the addition of hydrogen to intake charge. It showed faster combustion speeds than gasoline alone - which is good for both engine longevity and efficiency. However, effects were not really noticeable until around 6%. With hydrogen at atmospheric pressure, I'd estimate 6% hydrogen at atmospheric pressure to be around 360 liters per minute at high load, and perhaps 60-180 liters cruising. I can't see being able to do this without a pressurized tank.


Quote:
Originally Posted by bradlington View Post
One has to ask why vehicles in the early 1900's with such large bodies and weight still had really good efficiency out of the engine as far as BTU per liter of fuel .
Same family vehicle many decades later - third of the weight have same l/100 km consumption but the public are into believing that the efficiency is up high and non the wiser .

I don't know that this is actually true. The Ford Model T was mid-teens MPG, maybe ~15 average. However, this vehicle only weighed 900lbs and traveled no more than 40mph.

Starting in the late 30's and for decades after, the VW Beetle weighed in around 1650lbs. We still have these on the roads today and can see the fuel economy. Most people get around 23-25mpg, and they're not doing 65-70 on the highway.

In the 80's you could buy a Honda Civic which had a combined rating of ~26mpg, and weighed around 1800lbs. Maybe people did better than their EPA ratings, but not with the really equipped models.

The 88 Honda CRX HF was a 2 seater also weighing in around 1800lbs. It was rated for 44mpg combined, but this was, if I recall, without power steering or air conditioning.

Today you can buy a 4000lb 5 passenger car which will cruise at 45-50mpg at 65mpg with air conditioning, power steering, sound dampening, etc. etc., so I'm inclined to believe these fuel economy numbers from the past are revisionist history.

One thing that may really apply however was emissions. Gasoline used to have lead in it as a knock inhibitor, which allowed much higher compression ratios. Every point of compression is worth on average 2.5-3% fuel economy AND power, and I want to say some vehicles lost 4-5 points of compression when lead was removed. It's pretty clear to me why we shouldn't be blowing lead out of the tail pipes of hundreds of millions of vehicles, but also unfortunate we didn't have anything to replace it as an octane booster. My father claimed his 69 Camaro would get close to 30mpg on the highway (maybe 26-28mpg) at 55mph, and this was a pre-emissions vehicle, so no catalyst and a high compression ratio.

Last edited by Ecky; 01-16-2020 at 10:00 AM..
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