On 01/03/2010 12:37 PM, David Joyce wrote:
> <davidjoyce@doctors.org.uk>
>
> Ferg, It seems to me there are real advantages in having the battery
> forward (as Bob Harrison + convenient access). Even with a 914, a
> Woodcomp SR3000, a 17 amp hr Odyysey, and a very full panel, I found
> that a forward battery gave me an ideal C of G position with 3 lbs of
> lead fixed to the rudder post in the fin. 3 lbs is probably less than
> the wire needed to get decent performance from an aft placed battery.
I have an aft placed battery (well, actually two), and the wires needed
weigh closer to 1 lbs than 2 lbs (and not even substracting the weight
of the wires you would need anyway with a forward placed battery.) "Aft"
may sound like it is awfully far away, but in reality, it is just a few
feet more than on the footwell, nothing to worry about. I used the
copper clad aluminium wires from Eric Jones.
The 914 cranks superb, as if the battery is placed next to the engine.
I still don't know how my C of G will turn out (weather isn't
cooperating; I would have to trailer the ship to a weighing station, but
don't want to do this on roads covered with snow and salt), but I
suspect that with a 914 with dual alternator, intercooler and SR3000, an
aft placed battery has an advantage here.
To carry around 3 lbs of non functional lead, after all the painstaking
weigh savings during the built, is well, quite a waste to my opinion,
and something to be avoided if possible.
Frans
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