Pontiac GTO Forum banner

1 - 3 of 3 Posts

·
Registered
Joined
·
2 Posts
Discussion Starter #1
Looking for some help in identifying the engine in my newly purchased 67 GTO. The numbers on the block are 278436 with a YS right underneath them. I do believe this is a YS code engine with 335 horsepower. But how do I know if it is original to the car and if not what year would the engine be? Thanks in advance for any help given.
 

·
Super Moderator
Joined
·
5,782 Posts
Google up "Pontiac engine codes" and you should get several hits with reference information, including photos/diagrams. You'll want to start with the date code near the distributor to figure out what year the engine is, then use the casting code (low, down behind the passenger side head), and finally the YS. "YS" and the other codes like it were used in multiple years and sometimes meant different things depending on the year. That's why you always begin with the date code.

Bear
 
1 - 3 of 3 Posts
Top