Thought I would update the list on my fuel injection project. As you may
remember this is a homemade system on a tunnel ram type manifold and using a
Speed-Pro computer. Our first test at Maxton produced lots of torque
(especially for a 258 " engine and short stroke) and pulled extremely hard
in the mile with a resulting 179 MPH speed. When we got to Bonneville
obviously the situation, due to altitude and weather, would be different.
The beauty of any of these electronic system is its ability to adjust
automatically for some of these changes. And it did. We had the best plug
readings and most consistent exhaust temperature I have ever seen at
Bonneville.
Life would have been fantastic except I over estimated the ability of
the throttle bodies to flow enough air, and underestimated the airflow needs
of this small engine. My calculations indicated 1000 cfm total, guess I need
to recalculate. While running at 200 MPH for five miles this little engine
just ran out of air. So much torque at the bottom end that I had to back
pedal and short shift 1st and 2nd gear to keep from going sideways and
spinning.
Another great benefit to the electronic system is the data-logging
feature. Play it back and you can see all sorts of things you only guessed
at before. It's like having a built in data-acquisition system. Want to know
if the driver has his foot all the way down, or backing out? Throttle
position will tell the tale. Digital RPM really showed all the dips in the
course as the engine speed would increase 600 RPM as the Chevette would
levitate each time it hit one. And there is much, much more.
John Beckett
E/GCC, D/GCC, D/FCC
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