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305 bored to 350?

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Old 07-21-2004, 12:18 AM   #1
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305 bored to 350?

its this possible, i got into an argument with a fellow ta owner

he only said bored (he said the cranks were the same) and it was possible but ive heard that the water jacket widths are much less makin biggest bore 327.

its prob possible to make a 305 a 350 with stroke and bore, but he only said bore


is it possible to be bored that big?

is it possible to be bored and stroked that big?

how big can a 305 be bored?

how big can a 305 be stroked and bored?
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Old 07-21-2004, 12:21 AM   #2
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A 305 has a bore of 3.735" or so with a max over bore of .060" so the make CID that you can get is a couple more then 305. Not even close to 327 or 350.
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Old 07-21-2004, 12:46 AM   #3
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As for the stroke, a 3.75" (stock 400 stroke) can be put in with the same block preperations as a 350. Then you get a 328 cid (334 with .030" over).

But, that is not exactly the most cost efficient in terms of price versus output.
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Old 07-21-2004, 05:13 AM   #4
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only way to take a 305 bore to 350 bore size would be with sleeves and that wouldn't be very cost effective.
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Old 07-24-2004, 02:35 PM   #5
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If (and I really mean IF) you had a very good 305 casting with zero core shift, you might be able to bore it for fitment of Gen III SBC LR4 or LM7 repair pistons. The stock bore of those engines is 96mm (3.779"). The 0.5mm oversized pistons would net you a 96.5mm (3.799") bore. IF you were able to fit a 3.80" stroke crank from a 383HT into the case without having to cut it in half for clearance, you would net just under 344 cubes - somewhat of a "poor-man's" LS1. They're only 346 cubes, but many people refer to them as "5.7 liter" or "350".

With the right combination of parts, it seems possible. However, that begs the question "Why?" With a 4" bore block, you'd have a lot more cubes for the same efforts.
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