confused about my block

[86gmc23]

Just bought a old motor from a guy, he said it was a 350. I ran the numbers GM 14010207 and CFD 207. 14010207 States its an 1980-85 350 from a truck, however the CFD comes up as 1982 305. Do I have a 350 or a 305?

[winky]

I believe all the 350 say 5.7 on the back right behind where the heads sit

[Irish_Alley]

i hate to say it, cant take someones word on anything nowdays

[305chevy c-10]

if it dont have it there check top of bellhousing where tran bolt on should be stamped there gm 5.7 .all chevy blocks dont have 5.7 or 350 stamped on them i forgot what year they started so on them type blocks u just gotta run the # .or just pull off the head and see if u have a 4'" bore or better if its been bored .3.74 +/- it is a 305

[78chevyshortbed]

i have the same exact thing and im quite confused.

[chengny]

GM block casting number 14010207 =

Manufactured 1980-85 

350 CID

2 or 4 bolt main

Primarily for truck applications

[pholliday1]

For what it's worth I have seen people put 305 heads on a 350 to "try" to increase compression.

[Captkaos]

Casting number is a 350.

[Irish_Alley]

For what it's worth I have seen people put 305 heads on a 350 to "try" to increase compression.

arnt the valves different tho?

[Captkaos]

305 heads have smaller combustion chambers (more compression) and smaller valves (less flow at higher rpm)  They don't help a larger motor at all.