Just love to come back for a relality check!

[Mac]

Was just on a Mustang site and really, really learned something. Discussion was on differences between the 289/302 blocks. This came up and was just amazed.
" Also, if it is a later model (1981-1982 or newer) it will use a 50oz harmonic balancer instead of the earlier 28oz. Because of this, the 50oz balancer is nearly twice as thick as the 28oz, and in turn, will space your crank pulley about an inch farther out.
Didn't know it was that easy to tell the difference! Haven't figured out how to tell him how wrong he is. Happened to have a selection of flexplates and one flywheel. The flywheel has the big counterweight showing it to be a 50 oz balance. The two below flexplates show very little difference in balance weights, one is a 28 oz and the other is a 50 oz. Balance has nothing to do with weight or size. Which is the 50 oz flexplate? The flywheel is made to take either balance weight.
Dave of the Nord

 

[v-8power]

WOW
it's a wonder they were not "flaming" him as soon as he hit submit post. LOL

 

[bobbywalter]

dont tell em bout my 0 and 50oz balance 351's with tiny weights.

 

[baddad457]

I can see the difference between those two flexplate weights. The top one is wider than the bottom. As for the balancer remark, the 50 oz balancers have a much larger counterweight than a 28. In addition to that, the casting numbers are a dead giveaway to picking one from another, you don't have to rely on the size or thickness of he balancer itself, there are 28 oz balancers that are thicker than the 50's too, like the 289 Hi-po unit.

 

[Mac]

Well, the flexplate at the bottom is a 164T off an Explorer so it has the 50 oz. The one on top of it is for a '70' C-4 and has the 28 oz balance. The bottom one has the weight further away from center of rotation that accounts for the balance difference - make sense?
Dave of the Nord

 

[85_Ranger4x4]

Well, the flexplate at the bottom is a 164T off an Explorer so it has the 50 oz. The one on top of it is for a '70' C-4 and has the 28 oz balance. The bottom one has the weight further away from center of rotation that accounts for the balance difference - make sense?
Dave of the Nord

They also have a bunch of holes drilled in the meaty part of the top one between the weight and the ring gear.