Tuning with EGT

[justin ivan]

I have seen various discussion on this issue. I would agree that tuning by 
EGT alone can be dangerous becuase it can occur at different AFR's. Likewise 
tuning with AFR alone can also be a limitation becuase you don't know how 
close to the threshold before detonation you are. My comments apply largely 
to turbo efi cars as that is my experience but it is very possible to be at 
desired AFR but be 100+ deg F cool on the EGT, that means that ther is some 
room for more power to be made. I feel that both are probably better then 
one or the other. That being said I would rather have an AFR if I was 
limited to only one.
Justin


>From: "Jason R. Haines" <jhaines at lingenfelter.com>
>Reply-To: diy_efi at diy-efi.org
>To: <diy_efi at diy-efi.org>
>Subject: Re: Tuning with EGT
>Date: Mon, 5 Mar 2001 12:37:22 -0500
>
>We used to use EGTs for tuning but have switched to individual AFRs. We 
>have
>found the AFR to react much faster than the EGT. If you look at the time
>constansts for most thermocouples, the amount of time required to get to 
>90%
>of the actual reading is often measured in seconds while the UEGO sensors
>are measured in milliseconds. Also, you can be rich or lean and cause
>similar EGT's to occur depending on where the combustion is taking place 
>(in
>the chamber or in the exhaust).
>
>Just my $0.02
>
>Jason
>
> > Has anybody done air-fuel mixture tuning with exhaust
> > gas temp rather than O2 sensor?  I have read that the
> > thermocouple has a much quicker reaction time to high
> > heat/lean fuel conditions than an O2 sensor.
> >
> > If so, what are you getting for temperature readings?
> > I am wondering what temps (deg F) would equate to
> > optimum performance, without detonation.
> >
> > end
> > 
>--------------------------------------------------------------------------
>--
> > 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
>

_________________________________________________________________
Get your FREE download of MSN Explorer at http://explorer.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