Date: Wed, 16 Sep 2009 16:19:08 -0700
Reply-To: John Anderson <wvukidsdoc@YAHOO.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: John Anderson <wvukidsdoc@YAHOO.COM>
Subject: Re: 2.1 heads
In-Reply-To: <043701ca3712$62910290$6401a8c0@PROSPERITY>
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Actually although I don't recall exactly I believe it was '85 when the GTI got knock sensor ignition, and certainly all VW inline 4s (in the US market) had it within a couple of years. I think probably VW didn't want to take the time with the relatively low market (even worldwide) waterboxer which they probably knew they were abandoning soon anyway by then to bother. They did take a big step using the ECU to control ignition period on the 2.1, so knock sensing was probably more of a step than economically viable on a dying design. Although I'm EVless at the moment, the '93s I don't think had it either, not until the '95 (US at least EVC) did it come with knock sensor ignition, or perhaps it is just that the '93 has 1 and I know the '95 has 2. Of course late 80's Audi turbos had it, but I think it wasn't untill they changed the name to 100 in the US for the non turbo 5000 and got the high CR 2.3 (89?) that the normally aspirated did.
There are aftermarket systems, one could try, but I think it might be tricky given the wet liner design. I've wondered about this again in regards to Megasquirt (as integrated knock contol is quite reasonable to do.)
Don't think a late 80's Subie had it either though FWIW, not even a turbo car methinks, so can't knock VW for not putting it on a design they were soon to shelve.
John
--- On Wed, 9/16/09, Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM> wrote:
This is might be a great example why knock sensor ignition is so good, and
on most modern cars I'm pretty sure. My 88 740 Volvo has it.
VW inline four gas engines from the mid 90's have it, etc.
And also how sometimes, you can't quite get from 'here' to 'there' without
higher technology, like much mo' betta electronic engine management.
Waterboxer fuel injection is quite crude compare to say .........what Subaru
has with their 2.2 engine starting in 1990.
Not to go talking about that engine or conversion .........but there are , I
can think of, at least 3 things right off the top of my head, engine
management and electronics- wise, that those engines, and all the subaru
engines after that have, that the waterboxer engine management doesn't have,
and that poses either limitations, or at least, bi challenges.
If I had the time, I think I could retro fit Soobie fuel injection to a
waterboxer engine, including Air Mass Meter, Sequential Fuel Injection, and
knock sensor igntioin with no distributor, all of which the soobie uses, and
hadn't even been thought of very much when the waterboxer engine came out in
1983 in 1.9, then slightly upgraded for the 2.1 in 1986. Compared to what
is available now, that system offers pretty crude engine management.
So what is the real problem ? it pings ?
and of course, has GW been consulted and bugged about it, and several
different brands of gasoline have been tried, and the highest octane you can
get, and the timing's been fiddled with ? ??
Sorry to mention this even more ......but another much mo' betta thing
Subaru uses, compared to any waterboxer engine is......the timing is
completely managed by the ECU. There is no way to adjust the timing. The ECU
is completely smart about it, always optimizing the timing since it can
detect knock, and retard as needed, even many times a second. Waterboxer
engine management can't get anywhere near that. It's completely crude, and
thus limiting, in comparison.
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