Posted: Wed Dec 01, 2004 12:46 pmHas anybody ever tried/considered using a diesel engine
(I've got an old 5.7 GM) as a dyno brake in lieu of an eddy
current or a water brake?
What I'm thinking of doing is mounting the motor such that the
crank centerline is on pillow block bearings, and plumbing
large butterfly valves on the intake and exhaust.
Shutting down the ability to move air in and out of the diesel
creates load on the motor to be tested (driven by a shaft to
the front crank pulley) , and the torque measured by a hyd.
load cell.
The only downsides I can think of:
1) I'll have to likely cool the load motor due to the heat
generated by compression. No biggie there.
2) Won't likely be able to provide much load at low RPMs?
3) Might not provide enough load to load the target motor
down sufficiently? This would be really dependent on the
condition of the rings in the load motor (and head gaskets)
4) RPM capability of the load motor (no compressive loads
on the rods from the cylinders firing).
5) Takes up a lot of space. (not much you can do, there)
I'm looking at using this to load down a trans tailshaft, such
that I can test motor + trans at the same time. The primary
goal is to be able to do acceleration tests simulating the
weight of the vehicle. It'd be nice if I could get a reasonably
close HP/torque number out of it, but I'll settle for the load
capability.
Comments? The main reason I'm considering this setup is that
I have a couple of these motors lying around, and if it works
it'll make for a really cheap setup.
Thanks,
Dig
(I've got an old 5.7 GM) as a dyno brake in lieu of an eddy
current or a water brake?
What I'm thinking of doing is mounting the motor such that the
crank centerline is on pillow block bearings, and plumbing
large butterfly valves on the intake and exhaust.
Shutting down the ability to move air in and out of the diesel
creates load on the motor to be tested (driven by a shaft to
the front crank pulley) , and the torque measured by a hyd.
load cell.
The only downsides I can think of:
1) I'll have to likely cool the load motor due to the heat
generated by compression. No biggie there.
2) Won't likely be able to provide much load at low RPMs?
3) Might not provide enough load to load the target motor
down sufficiently? This would be really dependent on the
condition of the rings in the load motor (and head gaskets)
4) RPM capability of the load motor (no compressive loads
on the rods from the cylinders firing).
5) Takes up a lot of space. (not much you can do, there)
I'm looking at using this to load down a trans tailshaft, such
that I can test motor + trans at the same time. The primary
goal is to be able to do acceleration tests simulating the
weight of the vehicle. It'd be nice if I could get a reasonably
close HP/torque number out of it, but I'll settle for the load
capability.
Comments? The main reason I'm considering this setup is that
I have a couple of these motors lying around, and if it works
it'll make for a really cheap setup.
Thanks,
Dig