[Gmecm] Re: Fuel Economy

Sat Sep 17 16:09:09 UTC 2005

Hi Darrell:  I stick with my statement as to your specific question.

>> Interesting idea about using a WBO2 sensor, has anyone actually tried 
>> this?  I mean replacing a stock NB with a WB on a stock computer?  That 
>> in combination with changing the voltage threshold may allow you to set 
>> the AFR to a slightly leaner mixture overall.

Obviously if you add an interface box you can use a wb output into a narrow 
band
input.  I have a Zeitronix Wide band and it allows me to input a SIMULATED
narrow band signal into the stock ecm while using the WB to datalog actual 
afrs.

Sorry I got cranky about being "Corrected" for my errors.  (LOL!).

SOME people don't realize that word semantics are critical when you are 
typing.

"Clarification" would have been a better word sincce I wasn't technically 
wrong in
the first place.

Good luck on your projects!

Mark

----- Original Message ----- 
From: "Mark Romans" <romans at starstream.net>
To: <gmecm at diy-efi.org>
Sent: Friday, September 16, 2005 4:28 PM
Subject: Re: [Gmecm] Re: Fuel Economy

> No No No!   You can't run a wide band in place of a narrow band.
> The Wide band puts out a somewhat linear 0-5 v output.
> The narrow band puts out a non-linear 0-1 v output.
> I was datalogging with diacom with one pc and the wide band
> with a 2nd pc, datalogging the wideband afr, lamda, rpm and tps.
> Then going back and looking through each datalog and comparing screens to 
> set the afr's.
> Mark
> ----- Original Message ----- 
> From: "Darrell" <ndarrell at telusplanet.net>
> To: <gmecm at diy-efi.org>
> Sent: Thursday, September 15, 2005 9:08 PM
> Subject: Re: [Gmecm] Re: Fuel Economy
>
>
>> Cowen: (and all)
>>
>> Well, you are right, second times the charm.  Thank you for responding 
>> anyway, and getting a little action going on the thread.  A lot of this 
>> information will be useful, thanks to all who posted on the topic.  Some 
>> of it went way over my head, but I'm here to learn.
>>
>> Interesting idea about using a WBO2 sensor, has anyone actually tried 
>> this?  I mean replacing a stock NB with a WB on a stock computer?  That 
>> in combination with changing the voltage threshold may allow you to set 
>> the AFR to a slightly leaner mixture overall.
>>
>> I was thinking more of optimizing the ignition advance, perhaps advancing 
>> the timing a bit on light throttle acceleration, tweaking the 
>> deceleration enleanment up a bit, that sort of thing.
>>
>> Definitely the low restriction exhaust system will help, I used to drive 
>> a Camaro with cheap turbo mufflers, when the mufflers blew out my gas 
>> mileage went up by 10%!   Also thinking about 1.6:1 rockers for the 
>> exhaust valves to increase the flow a little.
>>
>> Not sure what I can do on the intake side, haven't really researched 
>> what's available for that engine, but I suspect not much.  Perhaps some 
>> 3.1l parts, I've heard that 3.1l heads make a fairly big difference.  A 
>> straighter intake tube with smooth sides rather than the ribbed stock 
>> hose may help as well, and perhaps a larger diameter MAF.  I'd actually 
>> like to get rid of the MAF altogether.
>>
>> I tend to agree with Bruce's observation, if you make more power, you 
>> need to get into the throttle less for the same effect, and fuel economy 
>> is tied to engine RPM and throttle position...  That is, if you can 
>> resist the temptation to put your foot in it.
>>
>> On 15 Sep 2005 at 16:33, Cowen wrote:
>>
>>> Wow!  A bit of vigorous action on this topic!  This IS
>>> my first rodeo, at least in this arena, and normally I
>>> might not have responded to Darrell, but it seemed no
>>> one else was, so I gave it a whirl.  I thought I put
>>> in enough "maybes" to draw out some clarification from
>>> the experts...  Well! I have been severely chastised
>>> for some poor writing skills!
>>>
>>> GAS said:
>>> > NB more sensitive at what ratio?  On what WB sites
>>> > are you referring
>>> > to?
>>>
>>> Not "NB more sensitive" at some other ratio, I
>>> understand NB to be very limited.  I meant to suggest
>>> that WB might allow closed loop with leaner AF ratios
>>> than stoich, which would be a probable benefit because
>>> although stoich is chemically the best ratio, "best"
>>> ratios vary depending on your needs, for power,
>>> emmissions, economy, driveability, etc...(hence PE
>>> mode).
>>>
>>> What sites?  I have to admit, I've only skimmed some
>>> of the WB sites found in a Google search, I don't have
>>> any suggestions for which is most detailed...  But
>>> don't worry, none of them I saw are trying to use NB
>>> sensors outside stoich!
>>>
>>> Gas also said:
>>> >The NB sensor is a switch centering around, and
>>> > being most
>>> > sensitive at stoich.  It's sensitivity deteriorates
>>> > the farther from stoich
>>> > (either direction) the AFR.  There are NB O2 sensor
>>> > voltage to AFR
>>> > curve charts on the net, that verify this.  By
>>> > design, NB sensors need
>>> > not be accurate at AFRs away from stoichiometric.
>>>
>>> Thanks for clarifying and expanding on exactly what
>>> I'd said about NB O2 sensors!
>>>
>>> GAS continued:
>>> >  There is WB O2
>>> > sensor technology
>>> > however, that allows for PCM closed loop operation
>>> > at ratios leaner
>>> > (or richer) than stoich.
>>> >
>>> > GAS
>>>
>>> Again, my case stated more eloquently. Now I know why
>>> no one else responded to Darrell! :)
>>>  **********************END TRANSMISSION**********************
>>>
>>>
>>>
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>>
>>
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