Fuel injection plugs

[Howard Wilkinson]

Pat:
    You wrote:
>I'm with you up to here. why a stepped automatic? <

    The reason for the stepped transmission is to increase gear range
beyond what the belt drive can provide.... you'd probably have to use
an axle ratio of 1x (not available as far as I know) to get high
enough gearing to load an engine down under virtually any conditions

You also wrote:

>aren't bobcats hydrostatic<

The early ones many of which are still in existance were not
hydrostatic and used a clutch and brake system like a Caterpillar with
a hydraulicly operated variable belt setup for speed range control.
The numbers such as 500, 510, 600, 610, and a number of others used
this system.  I converted one of these from a 2 cylinder Kohler engine
(16 hp) to a Subaru EA71 a number of years ago...... what a
powerhouse!

You also commented about noise in the FE engine with .035 lash..... it
wasn't any louder than most solid lifter engines, and was in a 2 ton
cab over truck so lifter noise wasn't noticed...... supprisingly some
of the Ford factory specs for lifter adjustment on some of the stock
FE engines with solid lifters which were high performance engines in
the early & mid 60's were at or very close to this gap.  You will find
this on some of the 390, 406, and 427 engines I believe..... Three
duces, solid lifter cam, and 400+ hp.  Those were real engines!!
H.W.



-----Original Message-----
From: Pat Ford <pford at qnx.com>
To: diy_efi at efi332.eng.ohio-state.edu
<diy_efi at efi332.eng.ohio-state.edu>
Date: Friday, April 30, 1999 5:13 PM
Subject: Re: Fuel injection plugs


>Previously, you (Howard Wilkinson) wrote:
>> Pat:
>>     It has been said that the greatest efficiency is achieved in
terms
>> of fuel burned per hour as related to horsepower output at WOT.
>> Engine power output is more or less proportional to CFM airflow in
a
>> spark ignition engine.  Thus power must be controlled by regulating
>> airflow as mixture is fairly critical.  Airflow may be controlled
in
>> one of several ways.  The common way is to apply a vacuum and
resist
>> induction....throttling..... this has the side effect of reducing
>> effective compression ratios at the typical 20% or so throttle at
>> which we cruise most cars.  Variable displacement would be another,
>> but so far has not been introduced.  Another is turbocharging a
small
>> engine on the theory that it will develop greater efficiency at
lower
>> power settings, and the boost will help it develop enough power
when
>> needed.  This has several downsides.... Compression must be
lowered,
>> or high octane fuel must be used or timing must be retarded, or all
>> three to prevent detonation... Lower compression drops efficiency
when
>> the turbo isn't boosting... retarding the timing doesn't help
output
>> or efficiency, and high octane fuel is expensive.  Turbocharging or
>> Supercharging are not the answer to our prayers unless an engine is
>> developed which has variable chamber size.  Even then there is the
>> downside that the smaller pistons and or shorter stroke will reduce
>> the ability to convert the cylinder pressure into torque.  We all
know
>> Pi*Rsquared....... figure the piston surface area and multiply it
by
>> the combustion pressure to get the push on the rod..... The longer
the
>> stroke, the greater the leverage available to turn the push into
>> torque.......  I like cubes....they make power.
>>     The other way to reduce engine output is to load it down to an
RPM
>> where the induction air flow is just enough to develop the power
>> needed to sustain the load.  The belt drive transmission you
describe
>> is probably the simplest sytem available to do this, and in
>> conjunction with a stepped transmission (automatic) one should be
able
>> to accomplish this.
>
>I'm with you up to here. why a stepped automatic? the justy used a
clutch,
>an electronically controlled set of pulleys and the reverse idler,
and dif.
>
>there was no other transmissions. the tach when you jumped on the fun
pedal
>went to around 3500 rpm ( it was around 10 yrs ago, I don't remember
the
>exact #) and then the pulleys did all the work. when you eased up on
the
>pedal the ratios changed gradualy from torque peak down to whatever
was
>needed to keep the engine load signal ( I believe it was duty cycle
from
>the injector) in a given range. It worked, and felt like driving a
diesel
>
>>In this scenerio the throttle (the one you step
>> on) would be directly in control of the transmission.... as you
press
>> the throttle the transmission gears down to allow the engine to rev
up
>> and develop power as needed.  The engine is always at full throttle
>> except at idle when it is throttled due to lack of any sort of
load.
>> Such a system should work within reason....it may require
conventional
>> throttling at very low power settings (dual mode operation).  It
would
>
>I should have mentioned the economy mode but as I said that was a
while
>ago 8-)
>
>> be more ideal with some sort of variable camming so that the engine
>> would develop efficient power throughout it's RPM range.  None of
>> these things is new or untried technology.  The belt drive is not a
>> very efficient system, but has a great virtue in simplicity.  It
has
>> been used for many years in such diverse applications as combines,
>
>I knew some combines had then ( I worked on 2 or 3 over the years)
>
>> skid steer loaders,
>
>aren't bobcats hydrostatic
>
>> variable speed machine drives, and
>> automobiles...... The Dutch built DAF used such as system.  Camming
of
>> an engine so that it will breath well at low RPM and also at high
RPM
>> can be handled in several ways.  The issue is overlap.  The greater
>> the overlap the less efficient at low RPM, but the better at high
RPM.
>> The simplest approach is the Rhodes type lifter which contains an
oil
>> chamber and bleed hole.... at low RPM the oil bleeds out more than
at
>> high RPM simply as a function of time.  I have greatly changed the
>> running characteristics of several engines which were over cammed
by
>> simply changing over to mechanical rather than hydraulic lifters,
and
>> adjusting lash until I was satisfied with the result...... One such
>> engine has run over 50K so far with .035 lash on mechanical lifters
>
>that must make a racket, but sounds fun
>
>> running on a hydraulic lifter high performance cam (FE series Ford
>> engine).  The other option would be a dual cam system of some sort
set
>> up with centrifugal advance/retard.  This would allow one cam to
>> advance the opening times, and one to retard the closing times of
two
>> sets of valves.  This would not be difficult to accomplish with
some
>> engines.  Caterpillar uses such a system on injector pumps on some
>> engines for timing advance... it is located right on the drive
gear.
>
>honda vtech does this doesn't it??
>
>>
>>                     Just some ideas.......     H.W.
>
>cool one thing I really like about this group is all the different
ideas
>that come up
>
>>
>> -----Original Message-----
>> From: Pat Ford <pford at qnx.com>
>> To: diy_efi at efi332.eng.ohio-state.edu
>> <diy_efi at efi332.eng.ohio-state.edu>
>> Date: Friday, April 30, 1999 7:40 AM
>> Subject: Re: Fuel injection plugs
>>
>>
>> >Previously, you (James Ballenger) wrote:
>> >>
>> >>
>> >> Howard Wilkinson wrote:
>> >>
>> >> >     The most reasonable way to control engine power output is
by
>> >> > gearing so that RPM is controlled by load.  A continuously
variable
>> >> > transmission system could allow an engine to operate at full
throttle
>> >> > all the time except at idle when it would need to be
throttled.
>> >> > Allowing the engine to always operate at WOT would greatly
increase
>> >> > efficiency.           H.W.
>> >>
>> >>     Ok, I know this isnt right.  If we had continously variable
transmissions,
>> >> we would be running them at peak torque not at wot.  VE is
greatest at peak
>> >> torque, the reason we rev engines higher to acheive high
horsepower is to combat
>> >> inefficient gearing.  At wot, there is significantly reduced ve
and not enough
>> >> time to get good mixture and combustion, therefore lower torque.
The reason
>> >> this is an asset is because it produces more torque per unit
time, ie power.
>> >> With a continuously variable transmission we could run the
engine all day long
>> >> at peak torque and get double or triple the gas mileage, more
power, and reduced
>> >> wear.  Again, im just a student so tell me where i goofed but I
have discussed
>> >> this with others before and feel somehat confident that this is
right.
>> >>
>> >> James Ballenger
>> >>
>> >
>> >years ago when the Subaru Justy came out and had the ECVT ( I
worked at a subaru
>> >dealer at the time) the engine would if you tromped on the gas
would go up to
>> >the peak of the torque curve and stay there. It was amazing, the
damn things were
>> >only a bit slowwer then a bmw M3 ( the dealer was also bmw and
saab dealer). We
>> >actualy had drags with the bimmer and saabs and the 3 cyl justy
was at the top
>> >of the cars we sold. The fuel economy was great just the lifetime
of the tranny
>> >wasn't so good. The ECVT was like a snowmobile pulley system but
the belt worked
>> >under compression, and there was a magnetic clutch that used iron
filings to transfer
>> >power. The othe funny thing was reverse was just an idler after
everything else,
>> >the early justy would go as fast in reverse as forward.
>
>
>--
>Pat Ford                           email: pford at qnx.com
>QNX Software Systems, Ltd.           WWW: http://www.qnx.com
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