I have just created a forum dedicated to small bore chevys 305/307, stop by, its new so bare with me im learning as i go, but get some posts up and get some people interested and im welcome to all ideas.../http://littlebore.16.forumer.com/
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.
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
thanks for that information. I got the BORE and STROKE backwards!!!
You are absolutely correct, the 302 has a large 4" bore but the stroke of the motor is smaller. Well, if I was to de-stroke the 327 to the 302 and then punch it out .030 ovr, that would make a 307.....correct?
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