Even though there is no IVR race this weekend, there is still a chance
we'll have an event next month, and there's a few autocrosses I'd like
to attend in the interim.
But I'm having an odd problem. Well, two, actually, but one you folks
can't do anything about. I bought a new chair for my home office this
evening, and it has a much higher back than my old one. I keep spinning
around thinking there's someone behind me ;-)
At the last IVR race before I melted the rear axle pinion and bearings,
I was having some trouble with Killer. The car would fire right up, idle
smoothly, run great and pull strongly up to about 5600, maybe 5700 rpm.
Then it would start cutting out smoothly, like it does if hitting the rev
limiter on the Crane HI-6 box. This would happen sitting in the paddock
in neutral, or pulling hard on course. It must be an ignition problem,
and not a fuel delivery issue, or the cutout point would be different
for idle and load, right?
At first I figured that the rapscallion who broke into the shop over
the winter and replaced my driver's suit with an identical copy that
was an inch or two smaller in the waist was responsible for turning
down the rev limiter. But such is not the case.
Last week I got to messing with it some. The setup is a Crane HI-6
ignition box triggered from the points in a Mallory dual point distributor.
We're talking a mostly stock Spitfire 1500 cc motor here, stock head, stock
cam, 9:1 CR, basically an SCCA Solo II FSP legal engine, with dual Weber 40
DCOEs choked down to within an inch of their life (actually 28 mm) and your
generic 4 into 1 header. Timing at 12 degrees BTDC, point dwell within
spec.
With Crane HI-6 ignition box, Crane coil, Mallory dual point distributor,
car runs fine up to 5700 rpm, then starts cutting out. When rev limiter
set to revs below 5700, motor cuts out at setting.
With Lucas coil hooked to ignition, Crane box completely out of the picture
car runs fine up to 5700 rpm, then starts cutting out. It isn't the
Crane ignition box. With Crane coil wired direct instead of Lucas it
runs fine to 5700, then starts cutting out. It behaves the same with
either coil, wired directly to power or through the HI-6.
With new plugs, new points, new wires, new cap, new rotor and the Lucas coil
still in place car runs fine up to 5700 rpm, then starts cutting out. Same
with Crane coil.
Lucas coil removed, Crane box wired back in, car runs fine up to 5700 rpm,
then starts cutting out.
So where in the fuel system should I start looking for the problem?
mjb.
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