Opel GT Forum banner

1 - 4 of 4 Posts

·
Pathologic Opeler
Joined
·
1,960 Posts
Discussion Starter · #1 ·
I get my 69 gt next week,but the current 1.9 engine is not the original,How do I determine if the engine is the higher compression or lower compression version.I asssume the 9/1 compression engine has more horsepower..and would be more
desireable.
 

·
OPEL-LESS!!!
Joined
·
2,116 Posts
1968-1970 have the 9:1 flat top motors and 71 and newer have dished pistons (7.6:1) if its not the origional you can check the head if it has not been replaced. remove the valve cover and on the drivers side of the car there is a 2 diget number near the gasket surface of the valve cover. these 2 digits are the year the head were made. OR remove the starter and there is a serial number behind the starter. the last 2 digits tell the year of the motor. another i have heard but not tried is to take out #1 plug and bring the motor to TDC and shine a pen light into the cylinder and check for flat tops or dished pistons. IDK if the higher compression motor has more horse but like you i would assume it does. good luck with you new ride!!!!!!!
 

·
Pathologic Opeler
Joined
·
1,960 Posts
Discussion Starter · #3 ·
compression

If the car requires premium gas..doesn't that mean it is the high
compression version?Does the high compression engine Knock
or run porely on low octane?
 

·
crazy opeler
Joined
·
558 Posts
no it doesnt require high grade, you only need to use that if you have over say 10:1 compression.
 
1 - 4 of 4 Posts
Top