Twin ECM Systems and KISS

peter paul fenske ffnsp955 at bcit.bc.ca
Tue Jun 30 06:03:31 GMT 1998


Howday Gang

A few people appear to be interested in supplemental 
injection.

Paxton and others supply a pair of injectors
that activate on boost. Thus you don't need 8 100#
injectors which usually lead to idle probs..

I have been playing with a PWM circuit namely the
Tl494. Works great. Can be driven externally
and 1 to 3.5 volts gives 4 to 99% duty cycle.
Using a divide by 4 or 3 from ign ref you could
toggle the thing. a two bar map then could drive 
the thing. And a LM1949 cct to drive extra injectors.

However been asked to consider using a 730 ecm.
At first seems impossible then started thinking.
It should work. but the code is tricky. There
are two cop timers which are tended by just about
every subroutine. So you have to deactivate every
thing carefully. But if we start playing with the
box controlling a 4l80E could be next

Oh yes the LT5 uses a switch box. The extra 
injectors are connected in parallel to the
main injectors when a signal is sent to the
switch box. This sort of code rewrite should
not be too difficult. All we have to do say
is turn fan#2 on or something like that when we
need extra fuel. 

Anyone else interested in above approaches. 
I dread having to use the 33# injectors on my
383 so this is where I am coming from

Later:peter





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