Vanagon EuroVan
Previous messageNext messagePrevious in topicNext in topicPrevious by same authorNext by same authorPrevious page (April 2005, week 4)Back to main VANAGON pageJoin or leave VANAGON (or change settings)ReplyPost a new messageSearchProportional fontNon-proportional font
Date:         Wed, 27 Apr 2005 11:24:36 -0700
Reply-To:     Old Volks Home <oldvolkshome@GMAIL.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Old Volks Home <oldvolkshome@GMAIL.COM>
Subject:      Re: advance mechanisms on digijet distributor?
In-Reply-To:  <20050426070307.92862.qmail@web53506.mail.yahoo.com>
Content-Type: text/plain; charset=ISO-8859-1

Although I don't have a map of the Advance Curves like Richard Atwell has for the Air Cooled variety on his site, I do have the specs shown my site for this distributor:

http://www.oldvolkshome.com/ignition.htm#V8384

Other answers follow below in your text:

On 4/26/05, Damon Campbell <damoncampbellvw@yahoo.com> wrote: > Hello list, > > I am trying to understand the various mechanisms that > control the timing on the early digijet. There is: > > * Static setting (just the twist of the distributor - > sets the baseline for centrifugal and vacuum) > * Centrifugal advance (rpm based advance... seems to > kick in around 1600 rpm or so. Where does it max out > at?) > * Vacuum advance (one half of the vacuum canister) > * Vacuum retard (the other half of the vacuum > canister) > > Static and Centrifugal are pretty straight forward. > The vacuum advance/retard is a little more confusing > to me. First off, does the vacuum canister actually > ever retard the timing?

Yes - 9 to 11 degrees at idle speed as per original factory spec (which would mean ideally when you disconnect & plug both vacuum lines, the "mark would move to about 6 or 7 degrees BTDC at idle (or even set at "static").

Secondly, the vacuum signal > adjusts the timing for engine load (i.e. lugging up a > hill at low rpms), right?

Yes, but not significantly. The purpose of the vacuum advance is to help prevent hesitation from a stop.

> > Is idle the max advance condition (as far as vacuum > goes), and then it just drops proportionately with a > lower vacuum signal, or...? On a standard 1.9L wbx, > how much of an effect of the timing does the vacuum > signal have (5deg...50 deg)? I guess a more direct > question is: at idle, if you unplug the vacuum line to > the distributor (and plug it), how much does the > timing change by?

About 5 to 7 degrees depending on the age/mileage of the distributor. At least it does on mine. I find that my engine idles and runs better set at about 2 to 3 degrees ATDC, so my distributor is showing it's age.

I hope this helps.

-- Jim Thompson 84 Westfalia 2.1 "Ole Putt" oldvolkshome@gmail.com http://www.oldvolkshome.com


Back to: Top of message | Previous page | Main VANAGON page

Please note - During the past 17 years of operation, several gigabytes of Vanagon mail messages have been archived. Searching the entire collection will take up to five minutes to complete. Please be patient!


Return to the archives @ gerry.vanagon.com


The vanagon mailing list archives are copyright (c) 1994-2011, and may not be reproduced without the express written permission of the list administrators. Posting messages to this mailing list grants a license to the mailing list administrators to reproduce the message in a compilation, either printed or electronic. All compilations will be not-for-profit, with any excess proceeds going to the Vanagon mailing list.

Any profits from list compilations go exclusively towards the management and operation of the Vanagon mailing list and vanagon mailing list web site.