Full Throttle at low RPM, or High RPM and low throttle - Page 7 - Fuelly Forums

Click here to see important news regarding the aCar App

Go Back   Fuelly Forums > Fuel Talk > Hypermiling
Search Today's Posts Mark Forums Read Click Here to Login
Reply
 
Thread Tools Display Modes
 
Old 06-02-2010, 02:16 PM   #61
Registered Member
 
theholycow's Avatar
 
Join Date: Apr 2008
Posts: 6,624
Country: United States
Send a message via ICQ to theholycow Send a message via AIM to theholycow Send a message via MSN to theholycow Send a message via Yahoo to theholycow
There's a link about lugging in my sig. Technically it is when you have severe predetonation, such that you hear explosions under your hood.

With the disappearance of manual transmissions, and doubly so with the appearance of knock sensors, its meaning has shifted to be as you describe, or to be when the engine is giving you the vibrations you described, or when it's making a growling sound.

I imagine that it will go rich with the TPS measuring WOT, but then why does it have a WOT switch if it can do that?
__________________

__________________
This sig may return, some day.
theholycow is offline   Reply With Quote
Old 06-02-2010, 03:00 PM   #62
Registered Member
 
thecheese429's Avatar
 
Join Date: Dec 2007
Posts: 82
Country: United States
Quote:
Originally Posted by theholycow View Post
...but then why does it have a WOT switch if it can do that?
I don't know, actually. I wish I had the documentation on my ECU, or could take it apart and tweak some settings.

I would imagine that it stays in closed loop operation (according to the speed sensor and MAP sensor, among everything else)(no, it has no MAF sensor) until the WOT switch (just a little micro switch) is closed, in which case it goes rich.


Would it be odd if I said that sometimes it seems to have more power around 60-75% throttle instead of 100%?
__________________

__________________
Until this moment all that I have known
Is death's attempt at imitating life
And for the first time I am truly alive
-Becoming the Archetype
thecheese429 is offline   Reply With Quote
Old 06-03-2010, 07:37 PM   #63
Registered Member
 
JanGeo's Avatar
 
Join Date: Jan 2006
Posts: 2,444
Country: United States
Location: Tiverton, RI
Send a message via Yahoo to JanGeo
Just remember that those BSFC maps are good for a proper running engine. If you have bad rings poor sealing knocking faulty timing all bets are off. In the case of worn out engine heavy loading is a no no you generate more blowby increase loading on rod bearings and crank etc better to use light acceleration and rev gently if it will rev with light throttle then shift.
JanGeo is offline   Reply With Quote
Old 12-06-2010, 04:22 PM   #64
Registered Member
 
Join Date: Apr 2008
Posts: 2
Country: United States
Re: Full Throttle at low RPM, or High RPM and low throttle

I was once told (30+ yrs) ago by a thermo teacher that in general the best mileage is obtained, all other things held constant, is low RPM & WOT providing you aren't detonating! This only makes sense because an engine is basically an air pump & the less friction getting the air thru the engine (blockage in the carb/air butterfly valve for injected engines) & low RPM for minimum mechanical friction in the engine helps maximize MPG. Think of other things that also help are low restriction air filt (K/N), 4 valves/cyl/bigger valves & low restriction exhaust system. High rpm is generally a destroyer of both mileage & engine life (diesels last 500000 miles because of their slow rpm) even though high rpm is where the HP is & the fun. Remember the HP equation has RPM in the top of the equation! Using these methods I have gotten as high as 71 mpg in my 95 civic VX & 20 in my old 97 powerstroke.
machworx is offline   Reply With Quote
Old 12-28-2010, 08:17 PM   #65
Banned
 
Join Date: Dec 2010
Posts: 3
Country: United States
Re: Full Throttle at low RPM, or High RPM and low throttle

Quote:
Originally Posted by theholycow View Post
Knock sensors are in every modern car.

You definitely want to avoid knocking.
Hell yeah! definitely!
intropiles is offline   Reply With Quote
Old 01-20-2011, 04:15 AM   #66
Registered Member
 
Join Date: May 2010
Posts: 17
Country: United States
Re: Full Throttle at low RPM, or High RPM and low throttle

Quote:
Originally Posted by machworx View Post
I was once told (30+ yrs) ago by a thermo teacher that in general the best mileage is obtained, all other things held constant, is low RPM & WOT providing you aren't detonating! This only makes sense because an engine is basically an air pump & the less friction getting the air thru the engine (blockage in the carb/air butterfly valve for injected engines) & low RPM for minimum mechanical friction in the engine helps maximize MPG. Think of other things that also help are low restriction air filt (K/N), 4 valves/cyl/bigger valves & low restriction exhaust system. High rpm is generally a destroyer of both mileage & engine life (diesels last 500000 miles because of their slow rpm) even though high rpm is where the HP is & the fun. Remember the HP equation has RPM in the top of the equation! Using these methods I have gotten as high as 71 mpg in my 95 civic VX & 20 in my old 97 powerstroke.


Diesels last because they cannot incur pre-ignition(detonation). That coupled with their heavy duty build qualities makes for a very stout, long lasting engine. If they could physically rev higher there's no doubt they would from the factory but the fuel power isn't there on large diesels and the sheer piston speeds they see due to long rod stroke is why they're rpms run so low.

The main killers of engines is pre ignition and oil starvation. Lugging an engine even equipped with knock sensors is silly. Remember; knock sensors work by reading pre ignition and retarding timing to deal with it. That means the engine is still seeing knock which could still damage a bearing.
__________________

Ilikebmx999 is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Fuelly Android App - eehokie Fuelly Web Support and Community News 2 07-14-2010 08:59 PM
Chart suggestions jeadly Fuelly Web Support and Community News 0 08-08-2008 02:46 AM
Landspeeds E-bike Conversion (Mk2) landspeed People Powered 5 06-06-2008 07:37 PM
How does Automatic Tranny choose? GeekGuyAndy Transmissions and Running Gear 5 08-13-2007 04:05 AM
ElectroCharger assist motor to retro-fit any car into a hybrid Matt Timion Hybrid Vehicles 2 10-09-2005 09:06 AM

» Fuelly iOS Apps
Powered by vBadvanced CMPS v3.2.3


All times are GMT -8. The time now is 12:46 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.