Chevy LS2 and Trans??? any real issues besides weight

Hey stol, question, what is the expected life of the belt in the
redrive? The only real experience i have with belted systems is in the
weighing systems we build for our industrial customers. I know belted
systems cause and transmit way less vibration to our platforms but
their life is far under the chains we used to use. Lucky customers
would get maybe 1 or 2 years out of a belt where as the the chains
never needed replacing. Miss treated systems would sometimes last
6mos.

Still the accuracy in weighing would far offset the cost of replacing
the drive belts so everyone is still happy.

also what is the cost of a belted redrive ? and where do i get the
high capacity belts when they need replacing ?

the only website i've read regarding the belted systems seems to
indicate belt manufacturers don't like this particular usage of their
products

thanx MrV

MrV wrote:

also what is the cost of a belted redrive ? and where do i get the
high capacity belts when they need replacing ?

the only website i've read regarding the belted systems seems to
indicate belt manufacturers don't like this particular usage of their
products

http://www.beltedair.com

Can I (or anyone) buy just the redrive? Are prices on the web? I
didn't see any list.

////////////////////////////////////////////////////////////////////////////////////////////////////////////////

The redrive is a BeltedAir unit I modified to fit on a Ford Block. They
are pretty damn stout units and all I needed to do was fabricate a new
block plate. I used all the other parts from the Chevy unit. I am sure
Jess@ BeltedAir has plenty in stock to fit Chevys.

Ben

Hey stol, question, what is the expected life of the belt in the
redrive? The only real experience i have with belted systems is in the

weighing systems we build for our industrial customers. I know belted
systems cause and transmit way less vibration to our platforms but
their life is far under the chains we used to use. Lucky customers
would get maybe 1 or 2 years out of a belt where as the the chains
never needed replacing. Miss treated systems would sometimes last
6mos.


Still the accuracy in weighing would far offset the cost of replacing
the drive belts so everyone is still happy.


also what is the cost of a belted redrive ? and where do i get the
high capacity belts when they need replacing ?


the only website i've read regarding the belted systems seems to
indicate belt manufacturers don't like this particular usage of their
products


thanx MrV

////////////////////////////////////////////////////////

Your right, the manufacturers of those belts will ""NOT"" sell you one
if you even mention the application is closely related to aviation. Ya
just say is for a conveyor system or some other industrial setup. I
think the belts are somewhere around 70 bucks.

well given sea level standard temp i'm looking at ~250hp at 3500 rpm
which from the graphs i've seen translates to about 360-375 lb-ft
torque at that point. now the graphs are few and far between but i'm
sure i can tweak it to atleast this level.

It's that torque that will kill the transmission. No car,
especially a 'Vette, needs 360 ft-lb of torque and 3500 RPM to cruise
the highway, even at 90 MPH. Torque places a LOT of pressure on gear
teeth so that the friction heats them up, and the relatively high RPM
just multiplies the heating. And we haven't even discussed bearings
yet.
All that power in the car gets used to lay a strip of rubber a
few feet long perhaps a few dozen times in the car's life. More than
that, and the gearing starts to suffer. It's not used for cruising.

Dan

Thielert uses a belt redrive on its *certified* conversion designed
for the 172. Belts are OK. But like gears, they need some sort of
flywheel on the engine crankshaft to dampen the power pulses, or the
reciprocating lash will destroy them. The prop wants to turn at a
constant speed, while the crank lurches between compression and firing
strokes, and if the belt or gears are expected to deal with all the
difference they soon fail. Flywheels add weight, especially if they do
a good job of damping, and the redrive adds weight and more failure
points, which is why Continental and Lycoming and Franklin built mostly
direct-drive engines with long strokes and large cylinders to get the
torque required at lower RPM. Some radials were geared, as were the big
V engines, but the cranks were so massive and the cylinders numerous
enough that the engine ran smoothly enough without a flywheel.
Even a direct-drive engine can have problems with the lurching
effect of the crank. Some wood propellers, notably the Fairey-Reed
types used on larger recips, had to be regularly checked for proper
bolt torque and charring of the wood where it met the crank flanges.
Torque pulses were strong enough to cause movement.
I liked Geschwender's Hi-Vo chain drive in which lash was
minimized by the chain's teeth expanding as they bent around the gears.
Much stronger. That engine, I believe, was used in cropdusters like the
Pawnee rather successfully.

Dan

On 13 Nov 2005 14:27:10 -0800, "MrV" wrote:

well given sea level standard temp i'm looking at ~250hp at 3500 rpm
which from the graphs i've seen translates to about 360-375 lb-ft
torque at that point. now the graphs are few and far between but i'm
sure i can tweak it to atleast this level.

MrV, as others have indicated there are a lot of design issues that
make using an auto engine a lot more of an engineering problem than
you might think.

First and foremost, you really need to rethink the idea of using an
auto/truck transmission, even a Corvette tranny. It just doesn't make
sense from an engineering standpoint. It's WAY too heavy for the job
being required, and you are carrying around extra gears and shafts as
dead weight. Not only is it dead weight, it's weight kinda behind the
center of gravity. Plus, the gears you would need to use simply are
not up to the task of transmitting even 50% power, given that you are
talking about an engine capable of putting out 250+. Now that you are
talking about adding bearings to support and isolate the propshaft,
you are adding yet more weight, this time well behind the center of
gravity. Are your wings going to have the ability to swing forward
and aft in order to compensate for the different weights of the
pilot/passengrs and luggage?

There was a guy who tried really really hard to make a go of
installing the Buick/Olds 215CID aluminum V8 in the back of a Long
E-Z. Look for E-Racer on the internet. He kept blowing them up.
Some of the blowups were because he did not research in the hot rod
community about the engine. Had he done so he would have learned that
you cannot bore the engine out to 300 CID and go racing. That doesn't
leave enough material to support the cylinder sleeves. There were
many other problems that caused catastrophic engine failure. His name
is Shirl Dickey. He finally decided to install a Chevy V-6 and last I
heard, he'd yanked it and was using a Lycoming.

This is the setup you are talking about, except that you keep
insisting you can use an auto transmission too.

Driving a prop using a driveshaft has been done successfully before.
See Curtiss P-39 Airacobra and P-61 King Cobra. But the driveshaft
was MASSIVE, as was the engine (Allison V12).

It's admirable to want to build a quiet airplane but it is definately
not a trivial matter. Are you an aerodynamics engineer? If not, you
should be doing some extremely heavy reading to see what such will
take.

Ben Haas has a very clean looking auto engine conversion using an auto
engine. But he has a racing background and the engine is not a stock
unit. He had built a number of engines that raced, prior to
attempting to install something in his airplane. In addition, he did
not design his airplane, he left that headache to Zenith.

Others have mentioned that engineering an auto engine conversion is
not a simple task. Designing and building an airplane is REALLY not a
simple task. You are suggesting you want to do both.

I wish you the best of luck.

Corky Scott

PS, seeking information from this group is not necessarily a good
sign. As Groucho Marx put it, "I would not want to belong to any club
that would have me." ;-)

PPS, for those who think stock Detroit engines are not up to the task
of putting out a continuous 65% power, is it time again for me to post
the description of what one auto manufacturer does typically to test
it's engines? If you've never read it, you will be agast at the
punishment.

thanx charles it was just an idea to use the auto tranny.

just wondering if it would work so maybe just maybe i would have less
engineering work even considering the weight.

on a side note: does anyone have any hard numbers on the weight of an
Ls2 configured to run? I just spent an hour at an off road shop that
is selling me the engine and they say the shipping weight fully
configured is less than 300lbs. this is an off road racing optimized
ls2 i'm considering purchasing. 2 of us actually picked the thing up.
i really don't believe this but these guys build atleast 10 cars per
year.

btw good info charles.

hey can u post those test procedures i would really like to see it for
myself

"Charles K. Scott" wrote

PPS, for those who think stock Detroit engines are not up to the task
of putting out a continuous 65% power, is it time again for me to post
the description of what one auto manufacturer does typically to test
it's engines? If you've never read it, you will be agast at the
punishment.

Yep, it's time, and this time, I'm going to save it, too. There is another
thread going somewhere else, about auto engines. It might be over in
RAPiloting.
--
Jim in NC

On Mon, 14 Nov 2005 18:36:12 -0500, "Morgans"
wrote:

Yep, it's time, and this time, I'm going to save it, too. There is another
thread going somewhere else, about auto engines. It might be over in
RAPiloting.
--
Jim in NC

Ok folks here it is in it's entirety, note, the comments in
parenthesis are sometimes mine. I originally posted this some five or
six years ago to this group:

Max Freeman is the engineer in charge of GM's Premium Engine programs
and has written an article for Mick Myal in the latest "Contact!"
magazine regarding the development and testing of their new PV6
aluminum 90° bank angle V-6. It's a lot of technical stuff about why
they chose this configuration or mechanical design over that, which is
why I like it.

He also wrote about the kind of developmental testing done on the
engine to make sure that customers get an engine they can depend on,
and I'd very much like to quote that section in full because it should
lay to rest the question of whether auto engines can take the kind of
power settings aircraft engines routinely manage.

"PERFORMANCE

The engine in production form for 1999 develops 215 HP at 5600 RPM and
230 foot pounds of torque at 4400 rpm. As a routine part of an engine
development program we tested the engine at full power, maximum RPM.
We ran it at 6000 RPM, pulling 215 HP at wide open throttle, for 265
hours. That's a continuous 265 hours of wide open throttle, far worse
than autobahn driving, because even on the German Autobahn, you
wouldn't be at 6000 RPM. THAT IS A STANDARD DURABILITY TEST.
(emphasis mine) We run many engines through this test as a matter of
course.

Specific development focus is on the crank, pistons, rods, block
structure, timing drive wear; we get a lot of full load cycles in a
hurry. It isn't necessarily designed to replicate customer driving
but to get development answers. Wear and fatigue are accelerated. The
test is particularly applicable in proving out dampers and their
effectiveness. If the damper is not properly tuned to the engine the
crankshaft will inevitably break in that time period. (note, this is
evidence you should not discard the stock damper when using the auto
engine for aircraft power)

A number of other engine tests are utilized. We use a variety of
specific tests to accelerate engine wear and to look at fatigue
failures. The cyclic endurance test is now called PTED (power train
endurance). It closely approximates cyclic durability. The engine is
cycled from its torque peak to its horsepower peak, at wide open
throttle, then down to idle, then accelerates up to shift points, then
back down to the torque peak and then horsepower peak. This test is
run for 400 hours. Once again, it's a wide open throttle test for 400
hours. The RPM for this engine, ranged between 4400 and 6000 RPM,
back and forth in about a 5 minute cycle. The dyno computer will
occasionally bring the engine down to idle, up to 6500 RPM shift
points, and then back to the 4400 - 6000 RPM 5 minute cycle.

Thermal cycle tests are run to define engine capability under cold
weather condition. We run the engine at full throttle at 4000 RPM,
bring it down to idle, stop it, switch the coolant valves to drain the
hot coolant, pump the chilled coolant from the chiller until the metal
temperature stabilizes at 0 degrees F. Frost forms on the outside of
the block, as the cold coolant rushes into the engine. When it
stabilizes at 0 F, we motor the engine, start it, come to full
throttle at 4400 RPM, the valves switch and the coolant temperature
starts to climb. It climbs back up to 260 degrees F. It takes 10 -11
minutes to complete one cycle. The engine must pass 600 cycles
without any sign of failure. We typically run 1200 cycles and a probe
test will run 1600 cycles. That's a (sic) excellent gasket killer
test. Head gaskets are the first to fail because of the rapid
expansion and contraction.

A powertrain endurance test simulates in-vehicle operation. The
Ypsilanti plant uses it for testing transmission. We, of course, use
it to look at engine performance. The equipment consists of an
engine/transmission combination, which sits on a dyno with large steel
inertia wheels. The inertia wheels are being driven by the
transmission output shaft, just like in a car. They cycle is brutal;
the engine is at idle in gear. The engine accelerates wide open to
6200 RPM, upshift occurs, 6200 RPM is reached, upshift occurs to 3rd,
6200 RPM is reached, upshift occurs to 4th, the wheels turn up to 135
MPH depending on the application. The second half of the cycle calls
for a closed throttle down to 70 MPH, then wide open throttle with a
downshift to 2nd, the engine goes back up to top speed, coasts down so
that the transmission selects down to a lower range. The engine is in
an overrun condition all the way down to idle; i.e., the engine is
being used for braking. That's one cycle. One transmission life
cycle is typically 12K - 13K cycles of the above test. We will run an
engine through 4 or 5 transmissions. This is a very harsh schedule
for the engine, particularly because of the overrun braking. Cylinders
and rings suffer the most on this test.

We run some idle tests to verify low speed operation. The engine is
run at idle for about 2000 hours to make sure of adequate oil flow at
idle.

We use all those engine tests in addition to fleet tests and extensive
vehicle road testing. The customer can be assured that the PV6 engine
is a thoroughly tested advanced design that matches or exceeds
competing offerings."

Corky's comment: I don't believe engine testing for aircraft
certification approaches this intensity, duration or severity.