My brother was given a motor from a 1970 Jensen. The heads have 4 valve cover mounting holes. No outside lower holes. The casting # is 1851509 and is on both heads. The intake casting is right for a 70-71 383. Any input would be great. thx matt

Well just from the casting number I can tell they are from the late '50s - early '60s. But a simple Google search for "1851509 casting" got me they were a 1959 HP head with 2.08/1.60 valves and the typical closed chamber which is listed at 73.5cc but is most likely 80 or more.

R.

Does it have the finned Jensen covers?

Kevin

Someone doing a 59 or 60 may want those heads. Do they have any bolt holes in the ends?

Yes, All the pulleys and other stuff. The 383 was 1970 only I think.

No end bolt hole. 4 each head.

Somebody probably swapped in the early closed-chamber heads in an attempt to raise the compression ratio.