New to list, have a question.

[Bruce Plecan]

-----Original Message-----
From: esc <esc at firstnethou.com>
To: diy_efi at efi332.eng.ohio-state.edu <diy_efi at efi332.eng.ohio-state.edu>
Date: Saturday, March 06, 1999 2:42 PM
Subject: Re: New to list, have a question.

For the effort your talking about, why not just use an eom ecm.  Junkyard
available,
and with some misc bits, maybe $150ish, be able to reprogram it, and do a
say 747..
If ya went 747 just reading programming 101 would be lots of help
Bruce


>>Eric,  I also have an early ProJection  ....  doesn't have the EGO
>>feedback though.  This is probably not going to be any real help
>>to you, but I thought I'd share some quick thoughts with you
>>
>>  . the projection is an alpha-n controller -- only uses rpm and
>>tps to determine fuel flow
>>
>>  . the temp input is, as best as I can determine, basically an
>>on-off kind of thing to enrich the mixture and energize the throttle
>>kicker, so I don't consider it a bona fide "input" for normal
>>operation
>
>Correct, it does nothing once the engine reaches normal temp.
>
>>
>>  . the "ego feedback" unit is only to keep the system closer to
>>stoic ......  a problem I constantly have is the unit always runs
>>rich .... it can be adjusted leaner, but then it will run entirely
>>too lean at certain points (I have a DPM watching an EGO, so I
>>get a little "feedback" myself  ;-)
>
>I have an old K&N O2 guage that I used before I got the closed loop kit.
>I still use it for base line tuning, it is very helpfull.
>
>
>>... if you agree with the above (that the ego feeback is to try to
>>keep the unit from running so rich, and maybe to prevent the operating
>>points where it also runs too lean, and that it's not to really improve
>>on the operating characteristics of the unit ....)
>
>It does help my mileage a lot, at the expence of throttle responce.  Thats
>why I installed an easily accessed disable switch for it.
>
>The main problem I have with the Closed loop kit has to do with how it
>modifies the TPS voltage.  Generally the baseline mixture is too rich so it
>leans it out.   If it(closed loop kit) leans the mixture very much then
>when you give a little more throttle it gets very lean and does not
>accelerate properly.  This kit does not function above 2/3 throttle, so I
>find myself often applying a lot more throttle than would otherwise be
>needed just to avoid the closed-loop-kit-induced flat spot.
>
>
>>  . then, consider that a MAP input might be more logical ??   I had
>>entertained the idea of either building my own ego feedback unit or
>>a map feedback unit -- or could actually sum the two together ??  All
>>that's needed is to sum the input from the tps with the conditioned
>>voltage(s) from the other devices.  To me, the map input makes more
>>sense and would elevate the unit from the status of simple alpha-n
>>controller to a simple speed-density unit (which their literature
>>claims it is anyway!).
>>
>>Tom Cloud <cloud at peaches.ph.utexas.edu>
>
>
>I agree that a MAP input is what I need.  Without it the Ram-air system
>will always be troublesome.
>The problem is how do I do it?
>
>I really like the throttle body part of the ProJection, but thats the only
>part I really want to keep.  I'm not all that happy with the controller.  I
>really want something that I can have more control over and that will
>accept input from more sources.
>
>Eric
>esc at firstnethou.com
>If it breaks, make it stronger.
>If it doesn't, try harder.
>'68 Big Block Bird
>'69 Spitfire
>'82(sort of) Camaro
>