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Kewl web site!! Catchy name:D

Eventhough I have a large bore 355 currently installed in my 6t6, I do have a small journal 327 that I would love to turn into a 302. The 283 that was originally in the car had a 6" inch crack along the side of the block and was basically trashed but the crank is in good condition. One of these days, I am going to build that motor but, not right now.

Dan
 

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I hope you get to do your 302. But it still is not a small bore engine. A 305 has a 3.75 bore and a 307 has a 3,875 bore. Correct me if I'm wrong. I had a 302 years back that would run rings around a 307/305. I have a 305 in my 65 that I'm dieing to see what it'll run. Hopefully, around June or July it'll be street ready. Dave
 

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If you have a 302, 327, or 350 block, they all have the same bore. 4.000. A 302 takes a 3.00 stroke crank, a 327 takes a 3.25 stroke, and a 350 takes a 3.48 stroke. By changing the crank and pistons, you can make any, or each of these engines. Boring a 302 .030 makes it a 305-306. NOT a 307. The bore and stroke of a 305/307 is different than the above combo's. Also again, The 302 and 327 came with large and small journal main bearings. And the blocks were made accordingly. With a good cam, a 302 will turn over 9000 rpm's. I had one that ran 9600 with a stick. Dave
 

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Ok,

302 + .030 ovr(approx 5 CID) = 307

And I know that the 307 is a 3.875 bore with a 3.250 stroke. The 302, as you mentioned, has a 4.00 bore but if I put the 283 crank,(3.00 stroke), that would equal to approximately 302 CID.

But this link is not about the large bore engines we are discussing. It is about the smaller mouse motors is what this thread is all about.

Dan
 
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