Date: Fri, 17 Aug 2007 23:29:17 -0400
Reply-To: "Daniel L. Katz" <katzd54@YAHOO.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: "Daniel L. Katz" <katzd54@YAHOO.COM>
Subject: Re: Weird ignition timing - '85 Westy
jay:
my guess is that, assuming the 14 deg part itself is accurate, this sweet
spot is actually 14 deg btdc, not atdc.
on our '84 1.9 l i find that setting the timing to 12 deg btdc (idle
stabilizer bypassed by connecting the two plugs together), yields
excellent all around results, and much better performance than the stock
setting of 5 deg atdc. in other words, i find that setting initial timing
17 deg ahead of stock works very well.
someone else may provide an explianation, but in some cases, i find that
more advanced timing somewhat mitigates the effects of low compression,
which may be the underlying issue.
in any case, i never subcribed to the 5 deg aftc specification. the timing
should be advanced to the point that the engine just barely pings, only
now and then, such as on a hard acceleration up a particular hill, or
occasionally at part throttle at certain speeds/loads with maximum vacuum
and centifugal advance. to power time an engine, you keep advancing the
initial timing until it just pings under certain conditions, then back off
slightly, so that it almost never pings. ideally, but not in practice on
the 1.9 l, the engine will be on the verge of pinging at all loads and rpm
ranges.
dan
On Fri, 17 Aug 2007 18:11:51 -0400, Jay Brown <badkarma@TTLC.NET> wrote:
>I recently replaced the distributor on my '85 Westy (stock 1.9L) since my
>old one had a broken connector where the Hall unit connects. I got the
van
>started and timed it by ear before reaching for the timing gun. The van
>will barely run at 5 degrees ATDC (sounds kinda like a sick Harley) and
>won't smooth out and run without stumbling until about 12-15 degrees ATDC.
>
>Thinking something was wrong with my timing gun I took the van for a spin
>and everything seems great at the 14 degrees ATDC setting. Good
>acceleration, no backfiring on deceleration, running at normal temps at
>highway speed and around town. I decided to borrow a friends timing gun
to
>double check things and I get the exact same readings.
>
>I am stumped, what could make my timing be so far from stock?
>
>Thanks in advance,
>Jay Brown
>'85 Westfalia
>'72 Riviera
>http://www.geocities.com/vwcamper72
|