what are differences between a 67 300 and 65 300

[buzz61]

what are the differences in a 67 300 and 65 300?

[pontiac1953]

buick completely redesign all their engines for 1967, i don't know if the 1965 300 was a buick design or an oldsmobile design, using other division engines had already started before 1965. charles coker, 1953 pontiac tech advisor.

[Wildcat65]

what are the differences in a 67 300 and 65 300?

Should be the same engines. The 350 came along in 68 with a significant design change.

[Jim65Riv]

According to the Master Parts Book, the following part number differences are noted for the 300 engine:

Cylinder Head - 65 - Part #1374720 66-67 - Part #1396788

Crankcase, cylinder including pistons, rings, pins and main bearings - 64-65 w/4bbl - part #1396702 67 w/4bbl - Part #1394142

[buzz61]

what are the differences in the heads?

[wildcat1562]

the 64 is an aluminum head and block, nothing like the 5, 6 ,7
i have worked on them all
and find no changes
from 65 to 67
Greg

[ol' yeller]

I believe they are essentially the same when comparing base engines. In '65 the 300 was available in 2 barrel and 4 barrel configurations. Besides a different intake and carburetor (obviously), the High Performance (HP) ' 65 300 4 barrel version also had higher compression pistons. The heads were the same. In '67 if one desired a 4 barrel on a small V8, I'm pretty sure the only option was the 340. The 340 was a 2 year only option '66-'67. While similar, the 300 and the 340's are different engines. I don't think a 4 barrel version of the 300 was offered in '67. The other difference between '65 and '67 300's is the location of the exhaust flapper valve for the choke. In '65 it was located on the right (passenger) side exhaust manifold. In '67 (technically in '66) it was moved to the left side exhaust manifold. The exhaust manifolds were different '65 to '67. If swapping in a motor between these years a small change in the exhaust would need to be made. Or one could swap manifolds as any year manifold will bolt onto any year 300 V8.

The 300 engine was a Buick design only beginning in 1964 and ending in '67 with the introduction of the 350 for the 1968 line. It was a replacement for the all aluminum 215 V8. In '64 Buick 300's came with aluminum intake manifold and aluminum heads but a cast iron block. There is virtually no difference in the blocks '64-67. Both 2 barrel and 4 barrel versions were offered '64-65 with the HP version having the higher compression pistons. Any year 300 block '64-67 was interchangable (allowing for the HP difference) In '64 they had a funky hot water choke setup. In '65 the 300 went to the more conventional cast iron heads and intakes. This elimated corrosion problems created by dissimilar metals and helped with cooling issues as well. I have owned several '64-65's and also restored a couple. Just trying to straighten out some misinformation. Hope this helps.