Hey guys, I am on the quest for greater knowledge and would like to know the difference between the 1964 2bbl 300 and the 4bbl 300. I know that the 310/355 was torque and not displacement. Here is what I have so far: I know both engines are on the 300 block. I know that the 310 has a 2 bbl carb, intake manifold, and a 9:1 compression ratio. I know the 4bbl has a 4bbl carb, intake manifold, and 10.something:1 ratio. I read a post stating that the pistons were different from the 310 to the 355. I am not planning on doing this, but to make the above statement into a simpler question, if you had a 1964 2bbl 310, what changes would you have to make for it to be exactly like a 1964 4bbl 355? cam, carb, block, etc?
1964 vs 1965 (trying answer the future questions, too....) 1964 300 2 & 4 bbl engines have aluminum heads and intake on the cast iron block. Choke heaters on both are hot water operated. The 2bbl engine has dished pistons, the 4bbl has flat-top (increase in compression ratio). No difference in cams. Block color is silver. Great engine, but careful attention must be paid to head bolt torque to prevent blown head gaskets and to the torque for exhaust manifolds to avoid stripping the studs and/or causing the manifolds to crack due to over torquing (true for all the small 215-based engines). This is the only year for the aluminum heads and manifolds. 1965 300 2 & 4 bbl engines have cast iron heads and intakes. Carb chokes were heated by choke stove from the right manifold. Same deal with the pistons, which are interchangeable with 1964. There is some variance in engine output figures between the two years, and the '65 4 bbl engine has 0.5 less compression at 10.5. Block color is Buick engine green. This was also the only year for the cast iron 4 bbl intake. The 300/2V continued until 1967 as the base V8 engine and the blocks are interchangeable, but the 340/4V replaced the 300/4V in 1966. The intakes from '64/'65 do not interchange easily due to differences in water jackets and oil galleys, so you're looking at doing a head/intake swap, either way. The 340 four barrel will not fit either due to a higher deck height on the block resulting in a wider manifold. Otherwise, many components of the engines are interchangable up through the 350. The 300 was offered in the Special/Skylark and the LeSabre with a choice of 3/4 speed manual and the ST300. All 300 engines have the Buick/Olds/Pontiac (BOP) bell housing/transmission pattern, so there are a wealth of great repacement transmissions it will match up to. As for making it just like an original four barrel, you'll need the aluminum manifold and the carb, which was a Rochester. For my money, I'd vote for the manifold and a new 500 CFM Edlebrock/Carter AFB with electric choke. Same design, but new production quality. Cheers, John
