Go Back   EcoModder Forum > EcoModding > Hypermiling / EcoDriver's Ed
Register Now
 Register Now
 

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 10-30-2020, 08:19 AM   #1 (permalink)
EcoModding Pro
 
Join Date: Oct 2020
Location: Abilene, Texas
Posts: 74
Thanks: 9
Thanked 41 Times in 27 Posts
MPG aids

Back in 1975 we bought a Ford Pinto with the V6 engine and automatic. In the dash was a light that got brighter as the MPG improved, that was actually a simple vacuum gauge. This was shortly after the 1973 oil embargo. For years I have had a vacuum gauge mounted in my dash for that very purpose. Manifold vacuum is a great way to keep your foot from wasting gasoline. Driving while keeping the vacuum as high as possible is an easy/cheap way to save gas. Trying to get as much economy out of my 2.3 is priority one, and I already have a vacuum gauge I will put directly in front of the driver. I am sure most on this site already know this but it never hurts to restate easy fixes.

  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 10-30-2020, 10:53 AM   #2 (permalink)
Master EcoModder
 
Stubby79's Avatar
 
Join Date: Sep 2012
Location: Victoria, BC
Posts: 1,747

Firefly EV - '98 Pontiac Firefly EV
90 day: 107.65 mpg (US)

Little Boy Blue - '05 Toyota Echo
90 day: 33.35 mpg (US)

BlueZ - '19 Nissan 370Z Sport
90 day: 17.19 mpg (US)
Thanks: 75
Thanked 576 Times in 426 Posts
Same idea as running an MPGuino or other MPG gauge on a more modern car...if you know what the engine is doing, you can - if you choose - get the most out of it.

Been a while since I've heard of anyone using a Vacuum gauge, but it would be the tool to use if you were running a carb!
  Reply With Quote
The Following User Says Thank You to Stubby79 For This Useful Post:
Charlie Cheap (10-30-2020)
Old 10-30-2020, 01:52 PM   #3 (permalink)
Master EcoModder
 
freebeard's Avatar
 
Join Date: Aug 2012
Location: northwest of normal
Posts: 28,397
Thanks: 8,021
Thanked 8,837 Times in 7,293 Posts
I always liked the idea of a 5 or 6 inch diameter gauge on the rear firewall of a VW Beetle. That would keep the vacuum line short and it would be readable in reverse in the rear view mirror.

The XFi has an Eco-light that comes on to prompt you to short-shift the gears. I don't know the logic of it, it certainly doesn't tell you when to downshift.
__________________
.
.
Without freedom of speech we wouldn't know who all the idiots are. -- anonymous poster

____________________
.
.
“You belong to Universe” -- the voice in Bucky Fuller's head
  Reply With Quote
Old 10-30-2020, 03:28 PM   #4 (permalink)
Eco-ventor
 
jakobnev's Avatar
 
Join Date: Oct 2010
Location: sweden
Posts: 1,644

Princess - '92 Mazda MX-3 GS
House of Tudor
Team Mazda
90 day: 53.54 mpg (US)

Shirubāarō (*´ω`*) - '05 Toyota Prius Executive
Team Toyota
90 day: 54.88 mpg (US)

Blue Thunder - '20 Hyundai IONIQ Trend PHEV
Team Hyundai
Plug-in Hybrids
90 day: 194.72 mpg (US)
Thanks: 76
Thanked 709 Times in 450 Posts
Send a message via MSN to jakobnev
How/when is the vacuum gauge used really?

I'm thinking on highway cruise for example, without a gauge you'd give it enough gas to not lose speed, what would you do differently if you had a gauge to look at?
__________________




2016: 128.75L for 1875.00km => 6.87L/100km (34.3MPG US)
2017: 209.14L for 4244.00km => 4.93L/100km (47.7MPG US)

Last edited by jakobnev; 10-30-2020 at 04:01 PM..
  Reply With Quote
Old 10-30-2020, 08:34 PM   #5 (permalink)
EcoModding Pro
 
Join Date: Oct 2020
Location: Abilene, Texas
Posts: 74
Thanks: 9
Thanked 41 Times in 27 Posts
vacuum gauge use

As the throttle is opened on a carburetor engine, vacuum drops, and as the throttle closes vacuum increases. So, if one watches the gauge drop as the car accelerates, a slight decrease (backing off the throttle) can still give the acceleration needed but drop fuel consumption. Consider it the "sweet spot." Also, once the car reaches the desired speed, vacuum increases due to a drop in engine load. Driving at a given speed on level roads keeps vacuum high... therefore higher MPG. A vacuum gauge is an excellent tool for tuning a carb. motor, and I assume a throttle body that uses a throttle plate to control air-fuel mixture. A vacuum gauge can tell engine problems like bad valves, manifold leaks, bad carb gasket sealing, and dwell setting, plus more. Once it was a necessity in any garage/shop.
  Reply With Quote
Old 10-30-2020, 09:04 PM   #6 (permalink)
Master EcoModder
 
freebeard's Avatar
 
Join Date: Aug 2012
Location: northwest of normal
Posts: 28,397
Thanks: 8,021
Thanked 8,837 Times in 7,293 Posts
One picture can be worth a lot of typing:


https://cdn.shopify.com/s/files/1/16..._1024x1024.png
__________________
.
.
Without freedom of speech we wouldn't know who all the idiots are. -- anonymous poster

____________________
.
.
“You belong to Universe” -- the voice in Bucky Fuller's head
  Reply With Quote
Old 11-05-2020, 02:16 PM   #7 (permalink)
EcoModding Pro
 
Join Date: Oct 2020
Location: Abilene, Texas
Posts: 74
Thanks: 9
Thanked 41 Times in 27 Posts
Vacuum gauge

The Pinto had a rectangular light on the dash that got dimmer as MPG dropped...I think. I know it was a brighter/dimmer light not an analog gauge. Anyway my wife really liked it because she did not need to know how to read a gauge, but a light that changes with MPG was easy.
  Reply With Quote
Old 11-06-2020, 12:06 AM   #8 (permalink)
It's all about Diesel
 
cRiPpLe_rOoStEr's Avatar
 
Join Date: Oct 2012
Location: Porto Alegre, Rio Grande do Sul, Brazil
Posts: 12,808
Thanks: 0
Thanked 1,672 Times in 1,490 Posts
Quote:
Originally Posted by freebeard View Post
That would keep the vacuum line short and it would be readable in reverse in the rear view mirror.
IIRC nowadays most instruments are electric, with remote sensors instead of keeping pressure, vacuum or whatever inside the vehicle.
  Reply With Quote
Old 11-07-2020, 08:53 PM   #9 (permalink)
Luddite
 
deluxx's Avatar
 
Join Date: Apr 2018
Location: Tennessee
Posts: 205

ol-green - '96 Honda Civic LX
Team Honda
90 day: 50.11 mpg (US)
Thanks: 142
Thanked 78 Times in 65 Posts
I rented a box truck with this nice gauge.
Attached Thumbnails
Click image for larger version

Name:	photo_2020-07-09_11-40-48.jpg
Views:	490
Size:	34.3 KB
ID:	29518  
__________________

  Reply With Quote
Old 11-08-2020, 08:10 AM   #10 (permalink)
Master EcoModder
 
Ecky's Avatar
 
Join Date: Dec 2011
Location: New Zealand
Posts: 5,075

ND Miata - '15 Mazda MX-5 Special Package
90 day: 39.72 mpg (US)
Thanks: 2,902
Thanked 2,560 Times in 1,586 Posts
My Insight came with a lot of instrumentation: Lifetime fuel economy, Trip 1 fuel economy, Trip 2 fuel economy, Current fuel economy (avg since button reset, usually at the start of driving), and an instantaneous readout. There's also a battery charge/assist gauge and battery level.

After changing my engine out, I now have an MPGuino which measures the injector pulses and gives an extremely accurate gallons per hour and MPG figure. I also have a bluetooth connection directly to the ECU which gives anything else I want through an app on my phone. I commonly used it to see degrees of ignition timing, intake and coolant temperature, vacuum, throttle percent, and air fuel ratio (measured vs requested).

Attached Thumbnails
Click image for larger version

Name:	IMG_20200623_171647.jpg
Views:	65
Size:	63.9 KB
ID:	29523  
  Reply With Quote
Reply  Post New Thread


Thread Tools




Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com