Jump to content
HybridZ

Air/Fuel mixture running lean question


Guest tony78_280z

Recommended Posts

Guest tony78_280z

I know all kinds of possible side effects of running lean, but can running lean actualy hurt your gas millage? In my mind it makes sense, but I can't explain how. Supose you set your system to run just a little lean at cruise, it might actualy run better MPG, but if if is more than just a little lean at cruise, wouldn't that hurt milage? Somehow?

 

Maybe a dumb question. And y'all prolly make me feel stupit fer axkin... :twak:

 

Please explain how I am correct or incorrect.

 

Thanks

Link to comment
Share on other sites

Guest bastaad525

it'd have to be excessively lean. For best fuel mileage, you already want to run it pretty lean at cruise, like 14-15:1 air/fuel or even leaner.

 

Running way TOO lean though would cost power, the car would feel sluggish or starved, it might hurt mileage because you'd be into the throttle more just to accelerate lightly, so might result in less mpg's, especially in traffic or going from one light to the next.

 

But I'd be more worried about what it might do to the motor, lean=hot and hot is bad.

Link to comment
Share on other sites

Guest tony78_280z
it'd have to be excessively lean. For best fuel mileage, you already want to run it pretty lean at cruise, like 14-15:1 air/fuel or even leaner.
Right, at cruise you'd want slightly less. But too much less?

 

Running way TOO lean though would cost power, the car would feel sluggish or starved, it might hurt mileage because you'd be into the throttle more just to accelerate lightly, so might result in less mpg's, especially in traffic or going from one light to the next.

exactly! or to keep at a constant high speed (70mph) cruise.

 

But I'd be more worried about what it might do to the motor, lean=hot and hot is bad.

Right, but for this discussion we are not including these problems.

 

Thanks for the reply

Link to comment
Share on other sites

Guest bastaad525

You might want to check on the Megasquirt section, there's lots of talk there on cruise a/f ratios, I think some people have set it as lean as 17:1 under cruise??

 

I would think that the lack of power would become obvious as you get leaner and leaner, well before you'd get a real loss of mpg's

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...