The design of the computer cooling fan blades is intended to move some air
against little resistance, not act as a compressor. I imagine it might help
a bit but not as much as a true compressor, whether super or turbo charger.
If it actually works reasonably well to compress some additional air, you
would have a 'blow-through' situation which can cause some carb problems.
The suction needed to draw the fuel past the needle would then be absent,
replaced by a positive pressure that would inhibit the fuel draw.
'Blow-through' systems usually find a way to pressurize the float bowl.
Absent a fix for this phenomenon, you could go very lean at high throttle
and hole a piston. I think this would be the major thing to solve, how to
take a carb designed for 'suck-through' and use it as a 'blow-through'.
Vizard has a chapter on this that is well worth reading.
If successful, you risk dealing with gobs of power, decent mileage (20-25),
more heat, and the sight of 1380-engined Spridgets getting small in your
As for the gobs-of-power problem, hardened axles, a full Datsun clutch w/5sp
and front disc brakes are a good idea. A boost gauge and an O2 sensor are
good tools to protect your motor as your dial in the carb for its new
Just a note on the mileage: If you're adding boost to a spridget, high
mileage is not a goal. True value for dollar with a boosted motor comes
from trying to attain the LOWEST mileage you can achieve. When people ask
what kind of mileage I get with mine, I answer "the lowest I possibly can"
> I have a question...
> What would happen if I attached 2 fans (like high temperature safe PC fans
> for example) at the top of my carburetor, effectively pushing more air in
> the carburetor throat?
> In version 2 of this, I would have the fan speed linked to the throttle
> cable in order to have the fan speed controlled by the throttle (the more
> open, the faster they would turn)...
> Has anyone done that? Does anyone has any idea what the result would be
> - power
> - fuel efficiency
> - how the engine would react to that
> - what would be the risks
> - how it compare with a turbo
> - how it compare with a compressor
> Regards, Cyrille