Will a 260 Flywheel work on a 302?

ramseyt

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My Tiger has a 1980 302 #EOAE with the original 260 flywheel #C3OE-638OB. I just replaced the clutch and now have a vibration coming in at 1,500 rpm. The only thing changed about the engine was the new clutch. This causes me to suspect that the 260 flywheel "external balance" is less than that of a 302. Looking at the old clutch I see that it has 4 beads of weld stacked together near the perimeter. Also, there are 5 extra holes drilled in a mounting flange opposite the weld beads. It's as if the clutch cover is intentionally out of balance. I am pretty sure the old clutch came off the flywheel with the weld beads oriented toward the balance weight cast into the flywheel. Can anyone shed some light on this issue? Any help would be greatly appreciated.
 

0neoffive

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Round & Round

My Tiger has a 1980 302 #EOAE with the original 260 flywheel #C3OE-638OB. I just replaced the clutch and now have a vibration coming in at 1,500 rpm. The only thing changed about the engine was the new clutch. This causes me to suspect that the 260 flywheel "external balance" is less than that of a 302. Looking at the old clutch I see that it has 4 beads of weld stacked together near the perimeter. Also, there are 5 extra holes drilled in a mounting flange opposite the weld beads. It's as if the clutch cover is intentionally out of balance. I am pretty sure the old clutch came off the flywheel with the weld beads oriented toward the balance weight cast into the flywheel. Can anyone shed some light on this issue? Any help would be greatly appreciated.

The earlier 302 crank came as a 28 oz. external critter while the later ones were 50 oz. As for balancing by manipulating the pressure plate; sounds too scary to be true . . . .but then, we have seen some strange things happen over the decades.
 

66TigerMK1A

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; sounds too scary to be true . . . .but then, we have seen some strange things happen over the decades.

That's what I was thinking too :eek: but can't think of any other reason for the offset 'welds'
From what I've found, 302's had the 28 oz. right up to Dec. '82 so it's odd that the crank in a '80 would be a 50 oz. :O
 

michael-king

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From what I've found, 302's had the 28 oz. right up to Dec. '82 so it's odd that the crank in a '80 would be a 50 oz. :O

What we are all forgetting is that we dont know the history of the motor, its 37 years old itself, it could have a completely different rotating assembly in it to when manufactured. ... Thats why with old cars its always good to audit what you have... Who knows what a previous owner or workshop has done, modified or bogded previously to make it work at the time.
 

ramseyt

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Problem Solved!!

Based on the member suggestions I decided to reinstall my old clutch cover with its imbalance oriented toward the crank imbalance and the vibration is gone! I really appreciate the knowledgeable input to my issue.
 

theo_s

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Based on the member suggestions I decided to reinstall my old clutch cover with its imbalance oriented toward the crank imbalance and the vibration is gone! I really appreciate the knowledgeable input to my issue.

If you happen to have the oil pan off at some point, take the time to read the casting numbers off the crank... and also consider that the harmonic balancer might be either tweaked to match the rest of the assembly, or it might be a 50 oz-in. part.

Also, there is substantial availability of aftermarket (Ford Racing and others) billet steel or aluminum flywheels, with 50 oz-in, 28.2 oz-in, or zero balance, for $200 to $300: See Summit Racing for example (no affiliation here). When you figure out what your engine really should have, a billet steel or aluminum flywheel will give you substantially increased safety and possibly better performance than your current setup.
 
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