Primarily the bore size. The 305 has a bore of 3.74 and the 350 is a 4.0 bore. They share the same stroke on the crank. And no, you can't bore a 305 to a 4.0 bore.
No. That number was used for 302's, 327's, and 350's. (4" bore)
The bore and stroke is---3.740 bore and 3.480 stroke. STOCK 305
BORE is 3.740 and the stroke is 3.480
no. the bore and stroke are as follow the 305 3.736''x 3.48" and the 350 4.000"x 3.48"
3.736"
yes
No. There isn't enough material in a 305 to bore that far oversize without hitting water.
No. The bore size is different between a 305 and 350. The 350 bore size is larger.
Subtract 305 from 350 and that will give you the difference (or interval) between the two numbers:- the answer is 45. However, if you mean what is the difference between a Chevy 305 and a Chevy 350, then it is the difference between the engine bore (the cylinder) sizes. The 305 bore is 3.740 inches. And the 350 bore is 4.000 inches, giving the Chevy 350 20HP more then the Chevy 305.
4 inches like the 350
.060"