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Discussion Starter · #1 ·
I've been perusing Ford's website in an effort to narrow down the choice for a crate motor. I noticed some of them have or require a 28 ounce flywheel, and some require a 50 ounce. I can't seem to find any difference in specs that would give me a clue as to what the differences are that would require a different flywheel bobweight. All the engines I'm looking at are 302 or 347, and most have the "sportsman" block. Does Ford use different crankshafts in these engines?
 

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Discussion Starter · #3 ·
That part I knew. What I'm trying to understand is why Ford would use two different varieties of crankshaft in 2 otherwise identical engines...
 

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Joe

It takes less material (balance) if it is placed at a large radius, thus Ford placed the balance at the outside of the flywheel and also the harmonic balancer to reduce crankshaft mass. That's why when you 'zero' balance a stock-'ish' Windsor Ford you need slugs of Mallory metal to balance the crank.

If you are using new rods and pistons and they are lightweight pieces you may find that it is possible to zero balance the rotating assembly without adding Mallory metal. SCAT now sells a zero balance rotating assembly as a part of their standard catalog.

But to get back to your question, I don't know why Ford has 28 and 50 set ups.
 

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FFCobra Fanatic
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Generally speaking 302's are 50oz except for older ones and 347 or 331 strokers are 28oz like the 351 windsor. You would probably be getting a new flywheel and balancer anyways so its not that big of a deal. HTH

Mike
 

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Hi Joe,
Let's see, all small blocks except the HO 302 have a 28 oz imbalance. Ford 392 & 347 also use a 28 oz imbalance. Many race engines are now neutral balanced. Most flywheels I sell have a bolt on weight so the same flywheel will fit all applications with the change or removal of a weight.
Mike Forte
 
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