Yes, except he let us know that he had replaced the vacuum type distributor
with a centrifugal only unit from an A-series engine. Once that happened,
you have to compensate for the lack of a vacuum advance. 1500 factory
setting for late model 1500's is 2 degrees ATDC with vacuum disconnected.
Like you said, with all stock parts in place, when idle vacuum is hooked
back up on the stock dizzy, the timing immediately jumps up to about 6
degrees. Then as RPM increases, at highway speeds with light load, total
advance is about 30 degrees due to combined vacuum and centrifugal advance
curves. Since the distributor was replaced with a centrifugal only advance,
to achieve the same 30 degrees at speed, and to achieve the same idle timing
setting you would have to start with more initial advance. Also the smogged
1500 begs for more advance anyway. With stock pistons, I have been unable to
make one ping with as much as 25 degrees BTDC.
David Riker
74 Midget
63 Falcon
70 Torino
http://personalweb.sunset.net/~davidr
----- Original Message -----
From <Ajhsys at aol.com>
To: <pixelsmith@gerardsgarage.com>; <davidr@sunset.net>;
<wmgilroy@lucent.com>; <spridgets@autox.team.net>
Sent: Thursday, August 03, 2000 7:36 AM
Subject: Re: My Midget runs, sort of
> In a message dated 8/3/00 1:54:43 AM Eastern Daylight Time,
> pixelsmith@gerardsgarage.com writes:
>
> << Actually, it's just the opposite. The vacuum is setting it to 2 degrees
> ATDC and goes away when the RPM increases, but 10 degress BTDC is correct
> without vacuum. >>
>
> - - - - - - - - - - - - - - -
>
> Let's think about this. (I'm NOT an expert, I just like to sound like
one.
> I may still be incorrect.)
>
> Lets say you set the timing with a timing light whilst the engine is
running
> and the vacuum line is removed and plugged, at 10 deg BTDC. Then you
> reconnect the vacuum hose. The vacuum is going to advance the timing.
When
> you advance the timing, it moves further toward Before Top Dead Center.
It
> advances, or fires earlier. (At least, that's how it works in my car.)
>
> Correct?
>
> Allen Hefner
> SCCA Philly Region Rally Steward
> '77 Midget
> '92 Mitsubishi Expo LRV Sport
>
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