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Re: Distributor Question- 7.5 stamp

To: datsun-roadsters@autox.team.net
Subject: Re: Distributor Question- 7.5 stamp
From: Gordon Glasgow <glasgow@serv.net>
Date: Thu, 04 May 2000 21:04:05 -0700
Jim, the 7.5 on the distributor cam means 7.5 degrees at the distributor. But 
remember the
distributor is driven at 1/2 crank speed. That makes it 15 degrees at the 
crank. Add that to the 20
degrees initial specified for the Solex cam setup and you have 35 degrees total.

The smog distributor cam was 17.5 which means 35 crank degrees. That was when 
they used 0 initial
advance, again for a total of 35 degrees.

HIGHKIX4@aol.com wrote:

> For all:
> Was installing my new vacuum advance unit and looked under
> the breaker plate.  Centrifugal advance mechanism has
> 7.5 stamped on it.    Doing the math, with the non smog
> distributor calling for about 10 deg initial advance, then this
> one will give 17.5 at wide open throttle (no vacuum) and
> med revs or higher.  This would seem about right for not
> burning pistons (as much discussed recently), so then is this a
> non smog distributor??    And when I put everything
> together was happy to see the vacuum advance work
> quite nice and smooth when I sucked on the
> carb vacuum line, am curious how much additional advance
> is added with this, looks like quite a bit
> (15 or 20 degrees??).  I agree with the previous
> posts about total advance never to exceed 35-37
> degrees, and this is about true for many or most
> engines, so 15 or 20 degrees would be about
> right here also.
> Thanks!
> Jim,
> Chesapeake Va
> 67 pushrod 2L
> 72 510 wagon

--
Gordon Glasgow
http://www.gordon-glasgow.org



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