Keith asked:
> EFI huh, sounds interesting. What system does it use?
Meanwhile, Ron Bennett pointed out (thanks Ron):
>> Car can be viewed at: http://idt.net/~lotusf1/elan.htm
Eric Camiel also responded:
> Nice pictures! Does anyone have info on the fuel injection
system?
Well, it is an amalgamation of parts from various different
sources. Fred Miranda designed the thing himself. Fred has
considerable hands-on experience with custom EFI development.
It is a single throttle body type system, using a very nice
looking one-off Aluminum plenum / manifold that Fred welded up
from scratch. The remaining list of components is by memory
(my notes are at home) but I believe Fred said he used a Saab
throttle body, Autronic computer, Toyota high pressure fuel
pump, Mitsubishi ignitors, etc. I forgot what type of
injectors, which is kinda important, so (mental note) I need
to remember to ask Fred this question.
The Autronic computer uses a MAP type algorithm, and it has a
serial interface which can be used to tweak the look up table
data, from a laptop computer.
It uses a crank fire ignition system, with no distributor.
There is a cam position sensor (which actually replaces the
distributor) and a crank position sensor.
Using this system, the engine is quite flexible and smooth
running at any RPM, for moderate all the way to WFO throttle
conditions, but it does have a characteristic anomaly that
Fred has yet to get ironed out... When warmed up, and at low
RPM and light throttle, it exhibits a "hunting" mode, where
it wants to cycle up and down in RPMs.
This is a broad side of the barn guess, but I suspect that
there may be a minor instability in some part of the control
algorithm. It could have something to do with the fact that
this motor has an exceptionally light flyweel, along with the
characteristic time constants of the manifold pressure (or
other?) sensors.
When I get a chance, I may to try to debug this problem
myself.
Regards,
Erik
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