Go Back   EcoModder Forum > EcoModding > EcoModding Central
Register Now
 Register Now
 

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 02-10-2011, 02:03 PM   #21 (permalink)
The PRC.
 
Join Date: Oct 2009
Location: Elsewhere.
Posts: 5,304
Thanks: 285
Thanked 536 Times in 384 Posts
Quote:
Originally Posted by euromodder View Post
So it made the same power on less fuel, i.e. by leaning it.
I've tapped this elsewhere but maybe worth it here.

One of the techniques on older NA diesels (Pug 205 - where are you now ???) was to balance throttle against what the engine could make use of in terms of fuel. The theory was that if you overdid it, the effect was like smothering a fire with too much material. What you needed to do was balance it against usage to get the best. There was definitely a point where you got no more benefit from either higher revs or more throttle vs easing back and changing up.

As I understand it a turbo kind of reverses this - there is always too much air for the fuel being injected - unless you use the old fashioned (rotary pump) trick of turning up the fuel. That gave you more power but at the expense of smoke from the less than efficient burning fuel.

__________________
[I]So long and thanks for all the fish.[/I]
  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 02-10-2011, 02:16 PM   #22 (permalink)
Banned
 
Join Date: Aug 2008
Location: Australia
Posts: 43
Thanks: 0
Thanked 6 Times in 2 Posts
Quote:
Do you have any idea why acceleration wasn't better through the whole rpm scale, but was actually worse below 1500 and above 4000rpm, even though the pressure drop was greatly reduced?
My idea for this is explained in the article.
  Reply With Quote
Old 02-10-2011, 02:43 PM   #23 (permalink)
Banned
 
Join Date: Aug 2008
Location: Australia
Posts: 43
Thanks: 0
Thanked 6 Times in 2 Posts
I have made a slight change to the story, based on material on page 60 of the Bosch publication Diesel Engine Management (3rd edition), 2004, which covers power and fuel injection mass.
  Reply With Quote
Old 02-10-2011, 04:20 PM   #24 (permalink)
aero guerrilla
 
Piwoslaw's Avatar
 
Join Date: Oct 2008
Location: Warsaw, Poland
Posts: 3,691

Svietlana II - '13 Peugeot 308SW e-HDI 6sp
90 day: 58.1 mpg (US)
Thanks: 1,268
Thanked 721 Times in 458 Posts
Quote:
Originally Posted by Piwoslaw View Post
Do you have any idea why acceleration wasn't better through the whole rpm scale, but was actually worse below 1500 and above 4000rpm, even though the pressure drop was greatly reduced? Would this imply that just swapping the intake for something larger would harm performance and/or fuel economy when the driver's style keeps rpms between 1000 and 2000?
Quote:
Originally Posted by Julian Edgar View Post
My idea for this is explained in the article.
OK, I went back and studied the graph and text again, and I see that I was in error! Acceleration is actually better below 1500 rpm than with the stock intake. The y-axis of the graph is in g's, not in seconds, as I had thought.
My bad, terribly sorry about that.
__________________
e·co·mod·ding: the art of turning vehicles into what they should be

What matters is where you're going, not how fast.

"... we humans tend to screw up everything that's good enough as it is...or everything that we're attracted to, we love to go and defile it." - Chris Cornell


[Old] Piwoslaw's Peugeot 307sw modding thread
  Reply With Quote
Old 02-11-2011, 08:23 AM   #25 (permalink)
aero guerrilla
 
Piwoslaw's Avatar
 
Join Date: Oct 2008
Location: Warsaw, Poland
Posts: 3,691

Svietlana II - '13 Peugeot 308SW e-HDI 6sp
90 day: 58.1 mpg (US)
Thanks: 1,268
Thanked 721 Times in 458 Posts
Crossposting:
Diesel mods and testing
__________________
e·co·mod·ding: the art of turning vehicles into what they should be

What matters is where you're going, not how fast.

"... we humans tend to screw up everything that's good enough as it is...or everything that we're attracted to, we love to go and defile it." - Chris Cornell


[Old] Piwoslaw's Peugeot 307sw modding thread
  Reply With Quote
Old 02-11-2011, 10:15 AM   #26 (permalink)
dcb
needs more cowbell
 
dcb's Avatar
 
Join Date: Feb 2008
Location: ˙
Posts: 5,038

pimp mobile - '81 suzuki gs 250 t
90 day: 96.29 mpg (US)

schnitzel - '01 Volkswagen Golf TDI
90 day: 53.56 mpg (US)
Thanks: 158
Thanked 269 Times in 212 Posts
Quote:
Originally Posted by Julian Edgar View Post
New intake cost very little - maybe AUD$30
That homemade intake was my favorite part pvc, sacrificial coolies, and tape...

...and a cherry picker, and some vice grips and a wooden plug

http://autospeed.com/cms/A_112211/article.html
__________________
WINDMILLS DO NOT WORK THAT WAY!!!

Last edited by dcb; 02-11-2011 at 10:28 AM..
  Reply With Quote
Old 02-22-2011, 01:22 PM   #27 (permalink)
DieselMiser
 
ConnClark's Avatar
 
Join Date: Jun 2008
Location: Richland,WA
Posts: 985

Das Schlepper Frog - '85 Mercedes Benz 300SD
90 day: 23.23 mpg (US)

Gentoo320 - '04 Mercedes C320 4Matic
90 day: 22.44 mpg (US)
Thanks: 46
Thanked 231 Times in 160 Posts
Part 3 is out on this series. Browser Warning

Its amazing how the ECU keeps making performance worse and worse by starving the engine of fuel. Even so I still think that mileage should be up though.
__________________
  Reply With Quote
Old 03-08-2011, 12:15 PM   #28 (permalink)
Aero Wannabe
 
COcyclist's Avatar
 
Join Date: Dec 2007
Location: NW Colo
Posts: 738

TDi - '04 VW Golf
TEAM VW AUDI Group
90 day: 53.2 mpg (US)
Thanks: 705
Thanked 218 Times in 169 Posts
Part 4 is out with nice results. Fuel economy "appears" to have improved by 5% with a nice increase in power.

http://autospeed.com/cms/A_112228/article.html
__________________
60 mpg hwy highest, 50+mpg lifetime
TDi=fast frugal fun
https://ecomodder.com/forum/showthre...tml#post621801


Quote:
Originally Posted by freebeard View Post
The power needed to push an object through a fluid increases as the cube of the velocity. Mechanical friction increases as the square, so increasing speed requires progressively more power.

Last edited by COcyclist; 03-08-2011 at 01:51 PM..
  Reply With Quote
Old 03-08-2011, 12:49 PM   #29 (permalink)
Master EcoModder
 
JasonG's Avatar
 
Join Date: May 2009
Location: Charlotte NC / York SC
Posts: 728

05 DMax - '05 Chevrolet 2500HD
90 day: 18.48 mpg (US)
Thanks: 120
Thanked 56 Times in 52 Posts
Here is the link Browser Warning
__________________



I can't understand why my MPG's are so low..........
21,000lb, 41' Toy Haulers are rough on FE!
  Reply With Quote
Old 03-08-2011, 02:33 PM   #30 (permalink)
The PRC.
 
Join Date: Oct 2009
Location: Elsewhere.
Posts: 5,304
Thanks: 285
Thanked 536 Times in 384 Posts
I suspect that if you have a custom remap to a 1.9 TDI you would get these results even without the other changes.

__________________
[I]So long and thanks for all the fish.[/I]
  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