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Re: So Slow
> > The major issue here with the N/A I5 engines is that the distributor is
> > run off of the back of the cam shaft. When you fiddle with the cam
> > timing, the ignition timing is going to change as well.
> Yup, yup. But as the sprocket retards the cam timing, does it not also
> (via the distributor gears) retard the ignition timing? (and same issue
> regarding cam timing advance...) And is not retarded ingition timing
> preferable for higher rpms?
Yes, retarded will help the top end. My concern is that I don't know if
the effective change to the distributor will help or hurt us.
I traded emails with Mr. Franco himself a couple of years ago, and he
informed me that he was selling a kit to convert the N/A engines over to
a flywheel/magnet triggered ignition so that they could use the variable
As I recall though, the total price was pretty hefty. Something in the
neigborhood of $500-600 for the gear and ignition kit.
> This leads me to believe that the variable cam sprocket, assuming it
> starts the camshaft slightly advanced and then retards it as the rpms
> increase, would keep the engine at this peaky point of its powerband
> (try saying that 5 times fast).
As I recall the Franco gear went from 8 degrees of advance to 4 degrees
of retard, but don't quote me on that.
> Is there anyone out there that has used the Franco sprocket on an I5,
> or even a VW 4-cylinder? Anyone who knows how it works?
I've never used one, but I do know that it uses a spring and
centrifigual weight setup. As the cam spins faster, the weights
(somehow) cause the gear to retard the cam timing, and as the cam slows
down, the springs pull the gear back into an "advanced" state.
The other thing that didn't thrill me all that much was that it needed
to be disassembled, cleaned, and relubed every 3-6 months.
Gary G. Erickson Secretary -- NW Quattro Club