Scott,
With all due respect to Ron, for he is correct for VACUUM ADVANCE
distributors, you described yours as dual point. The Ford dual point
distributors were mechanical advance, and did not have a vacuum
advance. In order to achieve the desired 32 degree full advance, it
would require a "static advance" of 13 degrees (assuming your 25 degree
number is correct.
With the advent of electronic points replacements, such as the Pertronix
and Unilite methods, the need for the dual point redundancy is moot.
You might consider a vacuum advance replacement, with 10 degree
mechanical advance limits (20 degree crankshaft) and 10 degree dialed-in
vacuum advance (adjustable on new vacuum units). Setting idle advance
at near 8 degrees, this gives you (2x10) crank, 10 vacuum, and 8 idle
for a total of 38 degrees - if your gas allows. You can always back-off
the vacuum setting with an allen wrench, or the idle setting. The
vacuum advance has the additional advantage of a large advance under
high vacuum (that's low pressure) that you would get on backing off the
throttle. No load, no ping problem, and better fuel economy even at 50
degree advance.
It is STRONGLY recommended that you take your good condition distributor
to one of the few mechanics that still have a Sun distributor adjustment
machine. He can not only dial-in your total advance, but select the
proper weight springs to let that advance curve match your needs. I
find that a straight line resulting in "all-in" by 2800-3000 rpm to be
most suitable.
Steve
Ron Fraser wrote:
>Scott
> Mechanical advance is generally from 18 to 28 degrees advance and is
>mostly at full advance at 2800 rpm. This will depend on your rpm driving
>range and purpose.
>
>Your total advance is can be from 32 to 38 degrees depending on how much
>advance your engine can take without detonating.
>
>There is an excellent article about distributor advance on the Ford Muscle
>web site.
>www.fordmuscle.com/archives/ignition.shtml
>
>Ron Fraser
>
>
>-----Original Message-----
>From: owner-tigers@autox.team.net [mailto:owner-tigers@autox.team.net] On
>Behalf Of Scott Hutchinson
>Sent: Friday, April 02, 2004 4:02 PM
>To: tigers@autox.team.net
>Subject: Distributor
>
>
>All,
>
>I know that there was a thread about distributor advance but I can't find it
>in my archives.
>
>I just had my distributor, (motorcraft dual point without vaccum advance),
>checked and set up to give full advance by 2800 rpm. I am getting 25
>degrees of advance from the distributor.
>
>Is this correct?
>
>Thanks
>
>
--
-----
Steve Laifman
Editor
http://www.TigersUnited.com
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