Hello all
quick question , I have a 425 from a 66 Olds D block,the head ID is located on the left side head at the back near the distributor, I thought the head ID was on the right side head at the front ?? any help would be awesome
thanks in advance

 

The heads were off at one time and put back on that way. Heads will work on either side. There may be exceptions but for the most part they'll work either side.

 

That's interesting, I always thought that both heads had identical stampings?

 

If the ID stamp in question is like the one in the picture, "VXXXXXX", it was on only one head. This only applies to 64-67 engines. Course both heads had the casting numbers and the letter or number codes.

 

Listed below are the identification numbers for '60's Olds heads. Mine are stamped with 394548 indicating that they are C heads.

ID/ Use Casting Code Year(s) CID CCs Number Notes A '65 400 80 383821 Unique 3/8" stud and nut rocker 425 mounting, using a 3-piece rocker pivot assembly; all except irrigation B '65 400 80 383821 Later '65 heads. Some use 3-piece B '65 425 rocker pivot asssembly. B '66 400 80 389395 Toro's and 442's got the big [2.072"] B '66 425 valves. Some use 3-piece rocker pivot asssembly. "-1" after the casting number on all B heads after April 21, 1966. C '67 - '69 425 80 394548 A/C '68 H/O's. Toro's and 442's got big. 455 valves. Rumored to flow the best of all BB heads. Can still be found. CA Very small ~3/8" ID lettering. D* '68 - '69 400 69.75 400370 All W-30. Non A/C '68 H/O's. All '69 H/O's. All big-valve. 455 69.75 400370 DA E '68 - '70 455 77,80 403686 455's in general, with 442/Toro's having big valves. F* '70 455 80 404438 W-30's. All big-valve units. G '71 455 80 409100 Generic 455 use, big valves in the usual applications. Ga '72 455 80 409100 W-30's, manual 442's used big valves. H* '71 455 80 409160 W-30's. Big Valve units. J '73 - '76 455 80,82 411783 All 445's. 'Smog heads', restrictive exhaust valve pockets. No big valve units. K** 455 80 413191 Ka** '73 - '76 455 80 413191 Marine, irrigation, industrial, W-30/Toro, 442 4-speed replacement head. Most were big valve units.

 

Below is the link. This should be a little more legible....

http://oldsjunction.classicoldsmobil...sfaq/ofhed.htm