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Now I think the 289 nad 302 are the same block. so can you stroke a 289 and come out with the same results as stroking a 302?
 

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Now I think the 289 nad 302 are the same block. so can you stroke a 289 and come out with the same results as stroking a 302?
The 302 is indeed Ford's idea of a stroker... as is the 289 to the 260.

All three blocks are identical, minor differences aside, and have a 4.00 inch bore. The differences in displacement are strroke - 2.65 (I think) for the 260, 2.85 for the 289, 3.00 for the 302. Interesting how the mechanics are arranged so that the stroke and displacement are so similar. :)

You can put any of the three crankshafts in any of the blocks, although you have to watch for some variations in the balancing.
 

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The 289 block has shorter cylinders than a 302 block. I know a 302 crank can be used in a 289 block without a problem, but stroker cranks for a 331 or 347 may pull the piston skirt below the cylinder bore. I don't know of anyone who has actually tried putting a stroker crank in a 289 so I can't say for sure, but I do know for a fact that the 302 cylinder bores go deeper than in a 289 block.
 

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The differences in displacement are strroke - 2.65 (I think) for the 260, 2.85 for the 289
260 and 289 shared the same stroke. 2.870" Bore was different. 260 had a 3.8" bore, 289 had a 4" bore.

The 289 block has shorter cylinders than a 302 block.
Another myth... Aside for minor casting differences, the length of a 289 cylinder and the length of a 302 cylinder is identical... I've measured both!
 

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The 302 is indeed Ford's idea of a stroker... as is the 289 to the 260.

All three blocks are identical, minor differences aside, and have a 4.00 inch bore. The differences in displacement are strroke - 2.65 (I think) for the 260, 2.85 for the 289, 3.00 for the 302. Interesting how the mechanics are arranged so that the stroke and displacement are so similar. :)

You can put any of the three crankshafts in any of the blocks, although you have to watch for some variations in the balancing.
Actually, the 260 and 289 have the same 2.87" stroke (as did the 221 that began this engine family), the 260 had a 3.8" bore and Ford opened it up to 4" to make the 289, then increased the stroke to 3" to make a 302. The 302 was the 1st time the stroke was increased, up to then all the displacement increases in this engine family were made by enlarging the bore.
 

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I just *knew* I should have reached around to the reference manual before shooting my fingers off. :p
 

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The 302 is indeed Ford's idea of a stroker... as is the 289 to the 260.

All three blocks are identical, minor differences aside, and have a 4.00 inch bore. The differences in displacement are strroke - 2.65 (I think) for the 260, 2.85 for the 289, 3.00 for the 302. Interesting how the mechanics are arranged so that the stroke and displacement are so similar. :)

You can put any of the three crankshafts in any of the blocks, although you have to watch for some variations in the balancing.
Actually, the 260 and 289 have the same 2.87" stroke (as did the 221 that began this engine family), the 260 had a 3.8" bore and Ford opened it up to 4" to make the 289, then increased the stroke to 3" to make a 302. The 302 was the 1st time the stroke was increased, up to then all the displacement increases in this engine family were made by enlarging the bore.
OK...maybe you guys can answer a question for me. If the 221/260/289 engines have different bores, then I presume the dimensions of the blocks are also different. Is this true? If not, then the inter-cylinder distance for the 221 block must have quite a bit more distance than the 289 block.
 

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Another myth... Aside for minor casting differences, the length of a 289 cylinder and the length of a 302 cylinder is identical... I've measured both!
Was the 289 block you measured a later model casting, maybe after the 302 was already in the works? I've talked to someone who swore that the 289 bore was shorter after he put a 302 crank in his 289 block. I'm not disputing your measurements, just trying to see if maybe there is a difference in the 289 block castings ::
 

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If not, then the inter-cylinder distance for the 221 block must have quite a bit more distance than the 289 block.
??
Bore spacing is the same for all Ford small blocks.. 4.38"
 

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OK, since the bore spacing is the same, then the thickness of the metal between cylinders must increase as the engine size decreases...correct? In other words, the 221 cid engine has the most metal between cylinders, and the 289 has the least?
 

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OK, since the bore spacing is the same, then the thickness of the metal between cylinders must increase as the engine size decreases...correct? In other words, the 221 cid engine has the most metal between cylinders, and the 289 has the least?
All of the variations in this family had thin wall castings, if you cross sectioned a 221 and 289 block you'd see more space in the water jacket between the cylinders of the 221 (roughly 1/2"), not more metal around the cylinders.
 

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OK, since the bore spacing is the same, then the thickness of the metal between cylinders must increase as the engine size decreases...correct? In other words, the 221 cid engine has the most metal between cylinders, and the 289 has the least?
All of the variations in this family had thin wall castings, if you cross sectioned a 221 and 289 block you'd see more space in the water jacket between the cylinders of the 221 (roughly 1/2"), not more metal around the cylinders.
Eureka! So the diameter of the water jackets decreased with increasing block size (221 to 289). Well now, that wasn't so hard to explain, was it?
 

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The only thing to look out for when stroking a 289 is that some of the kits require a 1 piece rear main seal, which you would have to use a later 302 block for i believe.


Dave
 

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Quote:
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Quote:
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OK, since the bore spacing is the same, then the thickness of the metal between cylinders must increase as the engine size decreases...correct? In other words, the 221 cid engine has the most metal between cylinders, and the 289 has the least?


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All of the variations in this family had thin wall castings, if you cross sectioned a 221 and 289 block you'd see more space in the water jacket between the cylinders of the 221 (roughly 1/2"), not more metal around the cylinders.


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Eureka! So the diameter of the water jackets decreased with increasing block size (221 to 289). Well now, that wasn't so hard to explain, was it?

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Correct me if I'm wrong...But aren't all small blocks "Siamesed Thinwall Castings?" Meaning the cylinders are connected, no coolant between them?
 

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The differences in displacement are strroke - 2.65 (I think) for the 260, 2.85 for the 289
260 and 289 shared the same stroke. 2.870" Bore was different. 260 had a 3.8" bore, 289 had a 4" bore.

The 289 block has shorter cylinders than a 302 block.
Another myth... Aside for minor casting differences, the length of a 289 cylinder and the length of a 302 cylinder is identical... I've measured both!
The "302 bores are deeper" myth has been traced (many say) to some mid-60s Ford promotional literature that had an exploded diagram of the "new" Ford 302 with notations pointing out differences between it and the 289. Among these was a note that said "deeper boreds than 289," or words to that effect. It was an error - apparently the diagram was published before the block dimensions were finalized.

I have a copy of that pic, Id postit if I had a real website ::
 

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Another myth... Aside for minor casting differences, the length of a 289 cylinder and the length of a 302 cylinder is identical... I've measured both!
Was the 289 block you measured a later model casting, maybe after the 302 was already in the works? I've talked to someone who swore that the 289 bore was shorter after he put a 302 crank in his 289 block. I'm not disputing your measurements, just trying to see if maybe there is a difference in the 289 block castings ::
they are all 5 1/8"
 
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