From: Knobdoodle on 13 Feb 2007 04:37
"Nev.." <idiot(a)mindless.com> wrote:
> G-S wrote:
>> Repeatable yes... accurate no.
> How do you know ?
'cause they don't register the load from the headlights, obviously!
From: Nev.. on 13 Feb 2007 06:12
> "Nev.." <idiot(a)mindless.com> wrote:
>> G-S wrote:
>>> Repeatable yes... accurate no.
>> How do you know ?
> 'cause they don't register the load from the headlights, obviously!
Good work, Yossarian :)
From: Knobdoodle on 13 Feb 2007 07:18
"sharkey" <sharkey(a)zoic.org> wrote in message
> Knobdoodle <knobdoodle(a)hotmail.com> wrote:
>> > Sharkey is popping around with his oscilloscope, so will see if that
>> > *is*
>> > going on in the car.
>> Oscilloscopes measure fuel usage now do they?
> Hooked up to the injector drive, yeah, you could get a pretty accurate
> _relative_ measure of fuel consumption, maybe +/- 1% if you really
> worked at it. It's not quite the right tool for the job, but it's
IF you already have the action of the injector (and fuel pressure etc)
benchmarked so that the amplitude and duration that you measure with the
oscilloscope actually means something.
Other wise all you're measuring is "bigger/smaller" or "longer/shorter"
which, as you point out, can give you relative info but not actual "fuel
> Hammo wanted to establish that bike regulators are no longer shunt
> regulators like old Truimph "zeners".
> Actually, I think I can establish that more easily with a half-decent
> thermometer: if the regulator is switch-mode, its heatsink temperature
> should go _UP_ slightly under headlight load, whereas if it's shunt,
> its heatsink temperature should go _DOWN_ under headlight load.
> Doing this experiment is left as an exercise to the reader.
Let's go the other way here; what alternator do you reckon a 5.7L EFI
Commode with all the fruit is equipped with?
100 Amp, 120 Amp, 150 Amp? (maybe bigger still)
A 100A alternator running flat-out at 15V would be generating 1.5 Kilowatts
of electrical power.
That would take 2 or three kilowatts off the engine and if you were shunting
all that to earth you'd need a heatsink that would be as large and glow as
cherry-red as a single-bar room-heater!
Does that REALLY sound like something someone would design into a modern
car?!!? (and to save using a $2 brush?)
From: Knobdoodle on 13 Feb 2007 07:25
> <sigh> Well yeah ! But... it'll be different this time !!
Gee... I haven't heard that quote since I attended my last
From: Knobdoodle on 13 Feb 2007 07:35
"Nev.." <idiot(a)mindless.com> wrote in message
> Knobdoodle wrote:
>> "Nev.." <idiot(a)mindless.com> wrote:
>>> G-S wrote:
>>>> Repeatable yes... accurate no.
>>> How do you know ?
>> 'cause they don't register the load from the headlights, obviously!
> Good work, Yossarian :)
Have a look at the post about the alternators-sizes Nev.
If your reckoning is correct you're shunting at least 1.5 kilowatts of heat
away to earth what there's no load.
Now go look under the bonnet and see if anything is glowing cherry-red.
If not; your assumption about how your charging-system works must be wrong.
[And if everyone thought that way then I'd be a crazy to think any