I swear that somewhere in a galaxy far far away and long ago I was told that the 391 manual flywheel was balanced the same as a 428. I'm looking at one of my assortment of flywheels and the 391 does have a balance pad in the same position and of the same dimensions as the one on my 428 flywheel.
Does anyone know about this?
It could solve a couple of problems for me...
TIA!

 

<table width="899" height="1697" id="table1" border="0" cellspacing="0" cellpadding="0"><tbody><tr><td width="660" height="12" colspan="11"></td></tr><tr><td width="4" height="2"></td><td width="60" height="2" colspan="3"></td><td height="306" nowrap="" valign="top" rowspan="4" colspan="8"> Crankshaft
332/352/360/361/390
These “FE” series engines all employ a cast iron crankshaft. The only real different is stroke.
The 332 crankshaft has a 3.30-inch stroke. Three castings were made during the life of the
332. All are interchangeable. The 352 is more involved, but just as interchangeable. Fourteen
variations of the 352 crank were produced. The 360ci engine, available only in pickup trucks,
used two crankshaft types during its 1968-76 service life. The Edsel 361 was produced with
two crankshaft types during its two-year run. The 390, which arrived on the scene in 1961,
employed 16 different crankshafts through 1976.

If you are seeking a forged steel crank for your 352/360/390/406/427 engine, you may opt for
an “FT” crank from the 330HD, 361 or 391. These engines, like the 410 and 428, are
externally balanced. This means proper balancing procedures must apply in your build. Where
the steel crank suffers to a certain degree is weight because there is considerable weight gain
both in the crank and flywheel. The weight increase in the crank is due to larger
counterweights. The “FT” crank also has a larger 1.750-inch front shaft versus 1.375-inches
for the “FE” shaft. The trick here is to turn down the “FT” shaft or opt for the “FT” timing cover,
harmonic balancer and pulley.


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The FE 332 was only installed in 1958/59 Ford & 1959 Edsel Passenger Cars.

1964/67 330 2V Medium Duty FT uses the FE 352 crank / 1968/78 330 2V Medium Duty uses the FE 360 crank.

1964/78 330 2V Heavy Duty & 361 use a specific FT crank.

391 4V FT crank is 391 4V only.
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330 2V Medium Duty FT use specific flywheels.

330 2V Heavy Duty, 361 & 391 FT's use a different flywheel.

NONE are the same as any FE flywheel.

Left: 6303 crankshafts / Right: 6375 flywheels.