170" or 200" or both?

[Anonymous]

Hello. I recently purcgased a '63 Comet, S-22, which advertised a 170" motor. On inspection I find that the block is a '66 200 (with 5 freeze plugs) but the head is a '63. The motor runs hot and I am wondering if I have a 170" head on a 200" block. Head gasket is shot as well. How can I tell the difference between a 200 and 170 head? Bore size? Are the pushrods the same? I have a few numbers and I was wondering if I could get some help in deciphering them and see if the parrts are compatible. Block: C6DE-6015 B, build code: 6H5D. Head: C3DE-6090-D then a casting mark like the top of a flat head screw then X8. Carb: C4GFB. VIN: 3J19U500000. Any help would be appreciated. Thanks, Curtis.

 

[CZLN6]

Howdy Back Curtis:

This puzzle is not unusual, in 40+ year old vehicles. The bad short block was likely replaced with a good running engine from a wrecked. Bolt out> botl in.

The C3 head and carb are likely holding you back. The head is a Small chamber, small valves, and small intake passages and carb hole. Since the head is not original, the big question is what head gasket was used. Hopefully they kept the adjustible rocker arms form the '63 head.

The carb is likely an Autolite 1100 for a 170. The closest tag I could find is a C4OF. That is a 1.1" venturi rated at 150 CFM.

The C6 block is a hydraulic lifter, seven main bearing. It is a good one.

All is interchangeable between this head and short block.

Adios, David

The

 

[Anonymous]

Thanks for responding so quickly. I looked on another web site which lists casting numbers and such like and it indicated that the head is from a '63 200". Does this casting still have the same small valves and intake bore as the 170"? Thanks again for writing back.

 

[CZLN6]

Howdy Back:

To the best of my knowledge, there were no production 200s in '63 model year vehicles. The earliest production 200s began to appear in the Fairlaine/Meteor lines in 1963 and becoame an option in '64. Some of these very rare early 200 were still four main bearing and solid lifter engines.

The C3 head casting was used on both 170s and 200s. The difference in compression was the flat-top pistons in the 170s and dished pistons in the 200s. An original C3 casting would have 1.52" intake valves and 1.26" exhaust. When these are rebuilt valves are almost always upgraded to newer, bigger sizes- although this is not the best head to bother with for a rebuild.

Your heating problem is likely not related to the mismatch of head and block.

Adios, David