Chris,
Good to hear from you again
Let's see if we can sort this out.
>> Anyway, a couple of items you can probably help me with please:
>
1. I have finished the ignition/dizzy switchover. (ie Mallory dual
point, 40K volt coil, Crane system
inside with proper shutter, etc.) I now have to hook up a new tach with an
electronic feed as opposed to the
gear drive on the original. The supplied diagram seems to show the three
blades on the bach of the tach get
hooked up as follows:
____ A
I B
I
____ C
with A getting feed from points side of coil, B to ground and C getting
power from a switched source.
My question is in regards to this (C) switched source. Should I go off from
the voltage stabilizer or from a
full 12 volt source (GREEN wire) ?>>
The signal wire from the coil's "-" terminal to the tach is traditionally is
white/slate. There was also a
white/black wire at that terminal that was the trigger wire from the OEM
electronic ignition. Earlier harnesses
wouldn't have had those wires, but a plain white wire with some OEM color coded
wire soldered to the ends
should keep things straight for later reference. You'll want full 12v. to the
power supply terminal. Solid
green is the correct color choice (not light green). The later harnesses had
another green wire running from
the "IN" side of the stabilizer to the tach. The only things powered by the
voltage stabilizer are the fuel and
temp gauges, mainly to keep normal voltage fluctuations in the harness voltage
from causing the needles to rise
and fall unecessarily.
>> The car has been running well enough, but on my way home from the
>Moss motors meet in Solvang, CA two weekends ago (where the Spitfar took a
>second in it's class, big surprise as it's the first "show" she has been
entered in), my traveling buddy in his 68 MKIII seemed to have much more top
end than I. True he has a 1500
with a header, yet this was a marked difference and seems as though I am just
topping out. We both have the
Weber DGV and I am getting the secondary to fully open. My question is: How
do I go about determining the
proper advance adjustment with the Mallory ? Is there something else more
obvious I am overlooking?>>
Congrats on the award. Sounds like you've been doing all the right things.
There are so many things that can cause top end performance problems. Looking
at the obvious: Are you two
running the same size tires? My autocross Spit won't do over 95 because I don't
have O/D and I'm running a
185-60 profile YoMamma tire. Bacically, I got no gear left at 6500 rpm. Double
check the float level in the
carb. A low level can cause fuel starvation at high rpm. As can a dirty fuel
filter. A header can give better
breathing when the load pedal is down. You simply get more burned gases out of
the way faster, with better
scavenging. Header wrap and ceramic coatings are a plus on headers for better
thermal efficiency. Double check
the position of both throttle plates when you fully depress the gas pedal. I
mean, watch the plates as someone
holds the pedal to the floor, not just operation the throttle from the engine
bay. Did you get the Mallory with
vacuum advance, or straight mechanical. Mines mechanical and the static timing
is set to 12 deg. BTDC. I used
the little notched tool that comes with the Mallory to limit the centrifugal
advance to 24 deg. So, I'm getting
a total of 38 deg. max advance. I've never had the car on a chassis dyno (soon
though), so all I can go by is
the seat of the pants feel. I'm also running twin DCOEs.
I can't remember what, if any, internal engine mods you've made. Are you two
running similar engines, other
than the header?
>> Thanks for weathering these novice queries, I truly appreciate having
>a source such as yourself and this list, and hope we don't get so off track
>with the list that the true knowledge base leaves in disgust.
Hang in there, all things come to pass !
Never fear asking questions on this list. As the old saw goes, "there are no
stupid questions". I know I don't
always have the correct answer, but I'm usually willing to offer up a
possibility.
Let me know what you find,
Charlie B.
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