looking at an engine for my 69.block casting is 3932386 which is used in both engines.heads are 3927186,which according to my chev casting book is also used in both motors.there is another head number for the 300 only.how do i tell which motor this is?

looking at an engine for my 69.block casting is 3932386 which is used in both engines.heads are 3927186,which according to my chev casting book is also used in both motors.there is another head number for the 300 only.how do i tell which motor this is?
camshafts are different and intake manifolds are too there was also a 370 hp motor ,solid lifters, high rise alum.dual plane intake holley carb

.how do i tell which motor this is?

If block has not been machined there is a 2 or 3 letter code stamped on the front block pad that identifies year/chassis / engine / Hp /trans the engine was originally had

Exp;
HW,HX; '69 Vette 350 /350Hp man
HY, HZ; '69 Vette 350 / 300Hp auto
CGZ '71 Vette 350/330Hp man

looking at an engine for my 69.block casting is 3932386 which is used in both engines.heads are 3927186,which according to my chev casting book is also used in both motors.there is another head number for the 300 only.how do i tell which motor this is?


I think the 300 hp used 2 bolt main caps instead of the 4 bolt main caps the 350 hp used. And if I recall, the 300 hp used an iron intake manifold and a Carter AFB carburator.