Date: Tue, 24 Jun 2008 11:26:33 -0700
Reply-To: Scott Daniel - Shazam <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel - Shazam <scottdaniel@TURBOVANS.COM>
Subject: Re: DJ Compression Ratio
In-Reply-To: <5ebe10a0806240349g6b00583jf061f300e7798804@mail.gmail.com>
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for the sake of technical pickiness,
let's say it would be more kosher to say there's a big difference btween
a CR of 10 and 9.7 to 1 .................
IF.........there is proper and even semi-radical valve timing and cam
profile, quite advance ignitioin timing, and very inhanced intake and
exhaust systems, and all that .........then, yes, 9.7 vs 10 is a
significant difference.
giving only two changes that I know of ........the CR and the fuel and
timing mapping in the ECU..........*nothing* else is much
differnt......same lame looking intake runners ( look at some subaru
engines, particularily the DOHC 2.5 for some nice obviously
flow-enhanced intake runners ) ..........*not to mentioin* hokey two
valves per cylinders and PUSH RODS !! ( what are 'push rods' ????
..........and 'rocker arms' ???...........are those ancinet things
associated with 'points'........whatever those are ??
Think you get my point - given how ancient and crude the waterboxer
engine is........the dif between 9.7 and 10 to one CR is nothing basically.
More : ( I do get carried away - following is just 'more' about 'how
to get there' engine performance and fuel economy-wise )
and besides...........
without KNOCK SENSOR ignition ........how can the engine even be really
'smart' about how much power it can produce ? It can't.
I don't think many people recognize that knock sensor ignition is a
feedback system - the ECU constantly pushes the timing as much as it
can.......and gets feedback from the knock sensor when timing is 'too
much' - conseuqnetly it's opptimized constantly according the whatever
ignition curve mapping the engineers put in the ECU>
with old and fashioned distributor that either ( 1.9 wbxr ) depends on
centrifugal and vaccum mechanical devices to make the timing 'about
right, roughly' most of the time........or as in the 2.1 ignitioin
timing is determined within the ECU -but STILL ..........it's guessing
at what is about the right timing for all rpm's, loads etc. - without a
feedback knock sensor ..........Ignition Timing Curve is just like A
CARBURETOR - it's a crude approximation that gets something within the
broad ball park of what would really be optimum.
If I was going to 'invest' time in trying to get more out of a
waterleaker vanagon engine ( and you WILL NEVER GET PAST Push Rods and
Two Valves per cylinder - though there's been at least one air-cooled
drag racing VW Bug engine with subaur 4 vavle OHC heads put on it ).........
If I just 'had to' try to get the most out of a waterboxer engine, in
the electronics dept. I'd try an aftermakret tunable engine managment
system.
Links is one. Expensive.
But then you hook up your lap top to your ECU and you prgroam in the
timing and fuel mapping that you want, even boost if you have a
turbo.....all of that.
and BESDIES Again - you will never get past the JOKE 'head gaskets' that
a waterboxer enigine has, and will ALWAYS have.
it is PURELY AN ADAPTED AIR-COOLED VW ENGINE.
I love what Pual G. said when he was here- we were ponidering our
amazment of how difficulut a water pump is to do on a waterboxer with
the engien in the van...........like they sure coulda made that easiier
if they really wanted to ! - and it's the main part that wears the
fastest too- 70K miles is all you can really expect for sure out of a w.
pump on a 2.1 wbxr engine - he said.................
"VW gave the engineers 30 days to come up with a watercooled vanagon
engine. " !!
THAT FITS - oh does it ever.
Subaru Engineers..........and all manufacturers check out what the other
manufactureres do ..............in 1990 when they were coming out with
the Subaru EJ22 engines - which is just a BEATUTIUFAL piece of
automtoive and motor engineering ............I'm sure after work at the
Saki Bars they just laughed themselves SILLY over how much the
waterboxer engine is a patch job and 'emergency upgrade' to VW's
traditionial pushrod Bug engine layout.
I 'do' waterboxer engiens all the time - cause I get them
easily..........cause they're around - I don't hate them........
but if you really wanting something enhanced and very worthwhile that
goes better, and gets better fuel economy and is more durable......
and has better throttle repsonse, and HOLDS A SETUP WAY, WAY BETTER Than
a waterboxer Vangon engine ............
there are much better more modern engines that will advance you light
years , and it can be inexpensive too if you do the work yourself...........
I'm, partial to subaru's.........but there are other modern good engines
too............
you can only get so far upgrading something in incremental steps. At
some point to really advance you need a whole new 'clean sheet of paper.'
No matter what you do to a horse-drawn wagon - put an engine in it,, put
a windshiled on it, put disc brakes on it .........
it can never be a car. you just can't 'get there' without stepping into
a whole other paradigm in design anc concept.
I have core and rebuild-able subaru engines for sale btw.......not
trying to push that. One of these days i'll have an extensive inventory
reduction sale.
What I would do - assuming one has the room for a spare vanagon
......and assuming one doesn't have 10 grand to just drop on a Soobie
conversioni................get some totally beater watercooled vanagon
cheap , .......and get a Legacy Subaru car cheap - they go for 300
dollars sometimes - and build up a soobie conversioin overtime while
keeping your good vanagon for trips and so forth. That way you are
never without a good running Vanagon. And when it's all dialed in, swap
it over to your good vanagon.
Only meant to say - didn't mean to make this about subaru-vanagons - (
use some other modern engine , that's fine too ) if you really want
enhacned performance and fuel economy and real delight in an engine
........you can't get there really well with the old hardware. it
costs more........yes.........that is a problem all right - but the
reward in the end.......wow !
Scott
www.turbovans.com
Chris S wrote:
> So how does it run compared to the stock MV WBX?
>
> I'm asking because I have a complete DJ WBX on the way, with ECU, to replace
> the 1.9L in my '84 Westy.
>
> Chris.
>
> On Mon, Jun 23, 2008 at 10:13 PM, Kim Springer <kimspringer@rcn.com> wrote:
>
>
>> Everyone keeps stating that the DJ Engine CR is 10:1, 10.5:1, etc.
>>
>> I carefully measured my DJ engine and it was 9.65:1. MV is 8.65:1.
>>
>> If you want to round up to 10:1, so be it, but, when it comes to
>> compression
>> ratios, 9.7 is a long way from 10.
>>
>> Kim
>>
>>
>
>
>