Date: Thu, 20 Dec 2001 14:54:26 -0600
Reply-To: Max Wellhouse <maxjoyce@IPA.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Max Wellhouse <maxjoyce@IPA.NET>
Subject: Re: Boston Bobs day at the dyno
Content-Type: text/plain; charset="iso-8859-1"
Bob and Listees: The answer may be to use the TWM Halmeter like I have on
my altech system. It's a 30 led gauge with its own O2 sensor. 10 red led's
10 orange led's and 10 green led's. Red meaning lean,, orange meaning more
or less stoichiometric, and green getting to thee rich side. Hal meter has
Fuel to air ratio approximates for the various led positions. Gauge(easily
dash mounted temp or permanent) and O2 sensor ran about $200, but beats the
hell out of tryingto tune the Hal Tech by"plug color".
The Haltech system would've undoubtedly been useful in Bob's dyno day, but
at $100/hr. playing with the laptop gets expensive.
Berg offers higher capacity Bosch injectors which I am contemplating on my
engine(still using the 170k originals, could THAT be my problem) and a Bosch
adjutable FPR. BTW, I have an earlier version of the Boston Bob ported but
not big valve engine. It runs real strong up to about 5200 rpm, but dies in
4th gear(no wonder with a 4.57 r/p and a .77 4th). 3400 rpm is a true 70
mph, but there is till inadequate torque at that RPM to pull those gears on
even the slightest of inclines. Prolly a great tranny for a TDI though.
Mileage is no bettter and no worse than the old motor(neither is the oil
pressure) at 7k mi on the overhaul.
Beginningto wonder just how tired my old motor really was. Old engine would
do a flat ground no wind 0-60 in 17.2 sec with the taller gears. Should try
to do that with the questionably programmed haltech in closed loop mode.
Also need to add some advance at the distro to see if that helps(already
running 40 degrees max at 2500 rpm).
Big jump to the twm twin throttle bodies to increase the airflow and Berg
will have to guarantee me stable or better mpg before I drop another $1500
into the induction system on this van. I could've had a Karl M TDI
conversion paid far if I sink that much more money in this project.
Dimwitted moose and Flying Squirrel
----- Original Message -----
From: "Robert Donalds" <bostneng@FCL-US.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Thursday, December 20, 2001 9:25 AM
Subject: Boston Bobs day at the dyno
fellow learkers and so forth mores
I spent the day testing vanagons on a chassis dyno with mixed results. The
truth of the matter is that everything I thought I observed by the seat of
the pants method was wrong. First on the dyno was the big valve engine in my
84 camper first run to warm the engine up made 50 hp at 3000 and a max
reading of 77 hp at 4600 RPM thats a nice start but the air fuel ratio was a
little lean second run fully warmed up 3000 RPM 41 hp and max power of 70 hp
at 4500 RPM the fuel air ratio is now off the scale its way to lean. Thats
huge loss of power amost 25 % at 3000 RPM from the one thing that nobody
seems to check air fuel ratio. OK the day is young so we can take this in
stride and I am sure this engine has the potental to make alot more power
because the 20% increase in air flow threwout the valves lift . after
checking the fuel pressure we desided temporarily boost the pressure used
the adjustment screw on a pair of vise grips clamped to the return line and
we got the gauge to read a steady 35 pds under load. (dont try this at home)
and we did another run no differance in power or the air fuel ratio. OK I
now have a problem that is more than I want to sort out on the $100 an hour
chassis dyno and its time to move on to the next van. I brought out the
family van blue bell with a stock 2.1engine it a stock 1984 7 passenger plan
Jane quick as a bunnie and Im sure its not as fast or as powerful as my race
camper. First run bang 3000 RPM 55 hp max hp of 74 hp at 4600 RPM air fuel
ratio right on the money mid 13s same thing second try. thats not what I
exspected but I keep repeting the things I am learning so far #1 fuel air
ratio is VERY important #2 the meter is running when you are on the dyno. At
this point the cars are stacking up behind me waiting to have a go on the
dyno, turbo jettas and new beetles. Home I go to get the next van and when I
pull back into the yard where they are testing and they signal me to get the
van on the dyno for my next test. this next van is on a 89 carrat automatic
this van has the ossy chip from Derek Drew and I have been driving it for a
day. My seat of the pants told me that the chip gave the van a little more
throttle responce maybe but not $250 worth. First run 52 HP and the air
fuel ratio is almost as lean as my camper and the automatic uses more power
so less gets to the rear wheel plus the engine has 118 K. next I replaced
the ECU with the orignal one from the van next run the max power is 56 HP
and the air fuel ratio is much better I gained 4 hp by going back to the
stock chip. at this point more cars are behind me and I have double tested
to confirm the results the daylight is fading and the temp is droping below
40 so its time to call it quits for the day. I do plan to do more testing
with both the big valve engine and the rockers and chip but not for a couple
of weeks In the mean time I am going to make myslf a little air fuel ratio
meter using a heated oxy sensor and figure out some way to get a nice
reading under load so I can sort out the lean conditions I found.
The moral of the story is # 1 seat of the pants doesnt mean much if anything
# 2 air fuel ratio is sooooo important to making good power # 3 tuning
affects not only power but engiine life It has been my experiance that the
air and watercooled Zamboni engines, the type 2 vans and aircooled vanagon
engines just don't servive for long if the air fuel ratio or timing is off
even a little. The reason I use these as an example is they are often pushed
to and past ther limits. the ones that live have been set up correctly
Derek wrote
Boy, that sounds frustrating to be under the clock like that and to need
more time to test and fine tune.
I recall something about how the rockers alone can do an OK job of
increasing the power but that for the health of the engine it is better to
run the rockers with the chip and not to run the rockers without the chip.
I also recall the chip seller indicating that the chip alone is not going to
do that much for people but this message was a little muted since, of
course, it would impede sales of the chip.
You do not say that the ratio rockers were installed. So I assume they
weren't?
Derek
disappointing is the word I would use to describe the day. I learned allot
about how critical the fuel mixture is. The other lesson is that fuel
pressure made no change in richen up the mixture. That is not to say that in
other conditions it might be helpful. I still have know idea why the big
valve engine ran so lean. I mentioned this to Greg at Greg's repair he
pointed out that just because I had checked each sensor as I installed them
he thought that the pin test in the Bentley book had great value. The reason
he gave was that the when checked this way you can observe the values the
ECU gets not just the reading at the sensor. point well taken and I will
check that out .
The chip test was interesting I thought it felt good and It might give a
like more throttle response but the fact is it made less power as a straight
add on. that's not to say the chip does not have value. I had emailed
Darrell in regards to the chip add on. he reported that with the digitool he
observed the chip tended to run richer and go lean and the stock chip tended
to be lean and go rich. There are many factors involved Darrel was driving
around town and I was doing flat out pedal to the metal pulls on the chassis
dyno going from 3000 RPM to 4700 RPM. It could be the rocker don't need the
chip the chip needs the rockers to make any increase in power. some more
testing is needed after a way is found to get the air fuel ratio dialed in
on both vanagon injection systems. the next round of testing will include
the ratio rockers
I have not desided how to post the results and what to post the dyno only
gives paper print outs the one thing I did not like about the system.
The company that offers this service is called podium performance systems
based in NH phone
# 1 866 dynoguy. Roger the owner travels the up and down east coast and has
testing days at tracks and shops. If there was enough interest it make it
worth his time it would be no problem to set up a day of testing give him a
call
now get back to work
B.Bob Donalds
http://www.bostonengine.com
as always
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