[Diy_efi] Making a fake O2

[Marc Reviel]

----- Original Message ----- 
From: "Adam Wade" <espresso_doppio at yahoo.com>
To: <diy_efi at diy-efi.org>
Sent: Friday, June 03, 2005 7:08 PM
Subject: RE: [Diy_efi] Making a fake O2


> --- jeff matthews <maple69vt at hotmail.com> wrote:
>
>> I have a 1996 Miata and 2003 Prot?g?.  They both
>> have the stock ECU's.  But because I get board
>> around the garage they both are turbocharged.  They
>> both need to run richer under boost.
>> They both have piggy back fuel and timing controls,
>
> Ahh.  THAT answered my question.  It's not the stock
> ECU dealing with the boost, it's an outboard
> controller.  I'm extremely surprised, especially with
> the Miata, that you can open the throttle and
> accelerate long enough to make boost, but not to
> switch the ECU out of closed-loop.  A lot of engines
> would go bang if you tried to run them that way, with
> narrow-band closed-loop.

FYI, I am just finishing a prototype of a twin turbo upgrade for the Porsche 
Boxster.  The test mule is a 1999 model, 2.5L, 11:1, no variable cam timing, 
and last year before they went to e-throttle.  I designed it for 
low-boost/earliest spool up - 2000rpm = 2.5psi, 2400 = 5psi. During 
part-throttle/mild acceleration, it is almost always running positive boost, 
and does remain in closed-loop. I have about 1200 miles heavy testing on it. 
So far, no issues at all (not even a CEL). No piggyback stuff, stock ECU 
programming.

-Marc


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