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Engine torque reaction arm?

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My guess is that it went with the change in motor mounts. The TR4 mounts were more compliant, I believe, likely to reduce engine vibration transmitted to the car. The snubber was likely added to help avoid tearing up the softer mounts, by people who like trying to spin the rear wheels.
 
In addition, mine seems to buffer the TR4 engine's tendency to rock a bit right after being switched off. The TR3 doesn't seem to do this -- possibly the difference in engine mounts Randall mentions.
 
Was this only used on the TR4 and not the TR4A? I don't remember it on my TR4A but that one had lived a long hard life before I rebuilt it. I did a quick search and Moss's catalog only lists TR4 for application.

I'll have to go check my other TR4A since that car is in very original condition but it's in storage right now.

Scott
 
Back in '65 I bought my first Triumph, an early '62 TR4. It did not have the torque reaction arm from the factory. The lack of it reared it's ugly head when the driver's side motor mount perished and the engine canted enough to bind on the big rubber lower steering joint. It momentarily locked up the steering until I got off the gas.

Needless to say, I replaced both motor mounts and fabricated my own torque reaction arm. It was mounted it at the back of the head linked to another rubber mount attached to the under hood bodywork. I didn't want a repeat of the locked up steering.
 
HerronScott said:
Was this only used on the TR4 and not the TR4A?
Click to expand...
Does not seem to be listed in my TR4A factory SPC. It also lists the same mounts as the TR4, so I guess that kind of kills my theory.

BTW, Joe Alexander is offering a reproduction of the arm, if anyone wants one.
https://www.the-vintage-racer.com/webroot/Engine_Plates/

Joe claims it ensures "a more efficient transfer of energy to the driveline", for what that's worth.

Looks like a quality piece, but I've not tried it yet. It's in the bin for my eventual "hot rod" TR3 motor.
 
Karl,

I just checked my 67 TR4A which is in very original condition and no sign of one. Randall also doesn't see it in the TR4A parts catalog. Have you seen this installed on TR4A's?

From the TR4 parts catalog that I have, I would guess this consists of the following parts under Front Engine Mounting:

133471 Bracket, engine restrictor 1
650325 Buffer, assembly, engine restrictor 1
612067 Buffer, rubber 1

I couldn't tell if there was a place to mount it on the TR4A frame.

Scott
 
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