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TR3 vs TR4 Engine Differences

To: triumphs@autox.team.net
Subject: TR3 vs TR4 Engine Differences
From: Jeff Williamson <jaws@mich.com>
Date: Tue, 19 Nov 1996 22:56:09 -0500
I've been following this thread for a few days now, and I think I can
verifiably disagree that the front plate does not have to be changed to
get the 4 motor to fit in a 3A. 

My TR3A was already fitted with a TR4A motor with what appeared to be
the original 4A end plate and motor mounts when I bought the car 18
years ago. Although the bozo that installed the motor probably should
have changed the plate and mounts, he force-fitted the engine by tilting
it slightly and drilling new holes in the frame for the motor mounts.
This worked for many years, but it eventually caused problems as the
front carburetor dashpot and the thermostat housing rubbed on the hood,
the fuel pump rubbed the steering column under extreme engine torque,
and the rear transmission mount eventually broke.

I recently rebuilt the car and the engine, and not being able to find a
TR3 end plate, replaced the motor mounts with the original large
rectangular TR3 type, and drilled new holes for the mounts. Although the
engine is level now, it sits slightly higher in the front than was
original --- But it fits!!!.  Although I replaced the original SU's with
Webers, there still seems to be ample room for the tall SU dashpots
under the hood, and there is no longer a clearance problem with the fuel
pump.

It was a lot of work, but necessity is the mother of idiocy, right?

Jeff Williamson
Belleville, MI
1958 TR3A

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