General theory on EFI

[James Ballenger]

	Always start VERY high so that you don't run too lean.  The formulas
will give you a general approximation.  But it is much better to run it rich
and have to clean the plugs a few times before you get it tuned down than
blowing and engine.  So always start on the rich side and tune down.  To get
a really good idea of what you are running without a dyno, you might
consider a wide band 02 sensor or Lambda sensor.  A normal 02 sensor is not
very effective outside of 14.7:1, but the wide band will still read
accurately much higher and lower on the range.  Feedback from a good sensor
would greatly ease your tuning w/o a dyno setup.

James Ballenger

>-----Original Message-----
>From: owner-diy_efi at diy-efi.org [mailto:owner-diy_efi at diy-efi.org]On
>Behalf Of Andy Laurence
>Sent: Monday, November 06, 2000 10:13 AM
>To: diy_efi at diy-efi.org
>Subject: Re: General theory on EFI
>
>
>>Yes, it really is that simple.  Determining pulsewidth is best done by
>>dyno testing, but there are formulas to determine pulsewidth 
>at maximum
>>torque using engine size VE and injector size.  If you have the proper
>>size injectors (another simple formula based on horsepower), it's
>>really just picking a number from one to ten ms, say starting with 2
>>ms sloping up to 8 ms, and the engine will run.  In practice, it takes
>>a bit of experimentation to arrive at the optimum settings and this is
>>a function of the sophistication of your equipment and your
>>experience.  If you are looking for a place to start, try Jeff
>>Hartman's book and Bosch's Gasoline engine management.
>
>Cheers, I'll have a look on Amazon.com for those books ... am 
>I not likely 
>to blow the engine if I run it too lean?  I suppose (seeing as 
>I don't own a 
>dyno) I could install the system in a car and tune it whilst I 
>drive it 
>around (friend in the passenger seat at the keyboard).  Has 
>anyone else used 
>the system on the site with a PC as the ECU, as I cannot 
>download the zip 
>file with the schematic.  It seems like a really good system, 
>especially 
>with all those in/outputs, although I will probably run it via Linux.
>
>Andy
>
>_______________________________________________________________
>__________
>Get Your Private, Free E-mail from MSN Hotmail at 
http://www.hotmail.com.

Share information about yourself, create your own public profile at 
http://profiles.msn.com.

----------------------------------------------------------------------------
To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes)
in the body of a message (not the subject) to majordomo at lists.diy-efi.org

----------------------------------------------------------------------------
To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes)
in the body of a message (not the subject) to majordomo at lists.diy-efi.org