Is there any truth to this.....

[Murgatroyd]

http://rib.net/forum/showthread.php?t=25933

 

[pvanv]

Yes. The old 25 and 30 are based on the same block.

 

[tohatsu_guru]

Partially true. Depends on the exact serial number. In the 80's there was no difference between the 25/30 timing and gasket.