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MG TD TF 1500 - Harmonic Balancer

Anyone know if any of the early British engines had a harmonic balancer on the crank? Seems awful strange to me there's none I know of on a T series engine. Anyone ever make that mod and it worked? I would think some of you race guys would have checked into this. PJ
PJ Jennings

More power to your elbow in looking, but I think last time around all we could find was larger than the xpag pulley.
Dave H
Dave Hill

I believe that mechanical engineering technology pre and post-WW2 had little ability to analyze and measure complex vibration issues. Sensors and vibration analyzing equipment only started to become generally available in the late 60's or early 70's as electronics and computers came into general use.
The MGB has a torsional vibration damper, as does the 6-cylinder Austin Healy engine, while the 1500 MGA engine has only a very crude riveted front pulley on a cast hub. But no crankshaft problems like the XPAG engine as far as I know. Presumably the heavier, stronger crank had enough fatigue strength that the MGA's torsional vibrations were not a problem.
I'm a metallurgical engineer (not mechanical)so my historical assessment of this issue may be incorrect: if anyone has
in depth engine design knowledge I'd be interested in their viewpoint.
T W Moore

"Both Frederick Henry Royce and Frederick W. Lanchester have strong claims to the invention of the vibration damper, with the latest research showing Rolls-Royce using a crankshaft slipper (friction) vibration damper on their 1906 30HP models; however, Royce had not submitted it for patent. Lanchester had developed a theoretical multi-plate viscous design in 1910 (patent 21,139, 12 September 1910). The brilliance of Fred Lanchester and his many developments was widely hailed. Royce developed a viscous damper in 1912 that was then further developed and carried through to the B60 engine of the 1950s.[1]

[1] Royce and the Vibration Damper. Tom C Clarke, 2003, ISBN 1-872922-18-X"

Tim
TD12524
Tim Burchfield

Click Archives, search Harmonic balancer, scroll down to Harmonic Balancer for the XPAG and read linked article. George
George Butz

Thanks George: the BHJ Dynamics article explains the subject well. The difficulty in coming up with an aftermarket solution or
adapting a damper from some other design is made evident.
My previous searches used the term "Torsional vibration damper" & didn't come across this reference. I've made a hard copy.
T W Moore

This thread was discussed between 23/05/2017 and 25/05/2017

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