HOME

  HELP

  SITE MAP
 

  Additives

  Cells

  Electrical Parts

  Joe Cell

  Spark Plugs

  Stainless Steel

  My Videos

  Favorite Sites

  Questions

 


2nd Amendment

BigFoot - Sasquatch

Black Powder Making

Build a Wood Tree Stand

Moonshine Stills

Hemp Revolution

Martin vs Zimmerman

 

 

 

Air / Fuel Ratio

   

What is the effect of changing the air-fuel ratio?

Traditionally, the greatest tendency to knock was near 13.5:1 air-fuel ratio, but was very engine specific. Modern engines, with engine management systems, now have their maximum octane requirement near to 14.5:1. For a given engine using gasoline, the relationship between thermal efficiency, air-fuel ratio, and power is complex. Stoichiometric combustion ( air-fuel 
ratio = 14.7:1 for a typical non-oxygenated gasoline ) is neither maximum power - which occurs around air-fuel 12-13:1 (Rich), nor maximum thermal efficiency - which occurs around air-fuel 16-18:1 (Lean). The air-fuel ratio is controlled at part throttle by a closed loop system using the oxygen sensor 
in the exhaust. Conventionally, enrichment for maximum power air-fuel ratio is used during full throttle operation to reduce knocking while providing better drivability. An average increase of 2 (R+M) /2 ON is required for each 1.0 increase (leaning) of the air-fuel ratio. If the mixture is weakened, the flame speed is reduced, consequently less heat is converted to mechanical energy, leaving heat in the cylinder walls and head, potentially inducing knock. It is possible to weaken the mixture sufficiently 
that the flame is still present when the inlet valve opens again, resulting in backfiring.

Engine Management Systems are designed to keep Oxygen from increasing power.

A modern system will automatically compensate for all of the currently-permitted oxygenate levels, thus your fuel consumption will increase.

This article is from the Gasoline FAQ, by Bruce Hamilton with numerous contributions by others.

Read more:http://stason.org/TULARC/vehicles/gasoline-faq/7-3-What-is-the-effect-of-changing-the-air-fuel-ratio.html#ixzz1hhblRLVw

 

   
   
   
   

 

Page Last Edited - 01/30/2016

    Copyright 2003   All rights reserved.   Revised: 01/29/16.                                             Web Author, daddyo44907
The information presented on this web site is for information purposes only. Should you decide to perform experiments or construct any device, you do so wholly on your own responsibility
-- Neither the company hosting this web site, nor the site designer author are in any way responsible for your actions or any resulting loss or damage of any description, should any occur as a result of what you do.