Hose clamp questions, 70-72

[Mike E.]

Since my previous question about hose clamps (expansion tank to radiator) met with such overwhelming response (1), I'm trying additional hose clamp questions. All regarding Wittek:
1) on the 3/4" heater hose, the new 70-72 JG says clamps should be 1 3/16 with DMC. I know the DMC is a typo (should be DCM) but what about the size? I have searched the Internet for listings 1 3/16 clamps with DCM to no avail. I have found DCM with 1 1/4" clamps. Should the 3/4" hose be 1 1/4" or 1 3/16" clamps?

2) on a big block air cleaner to valve cover hose, 1 1/2" clamps are used. I just looked at a 72 that had never been apart. Correct tired old hose with alligator-skin texture and original markings on the inside of the curved portion of the hose. One of the correct original clamps is dated 3/69 (not surprising) but the other one has identical stamping except instead of the date, has DCM. The question,finally, is what does the DCM signify?

[Terry M.]

Re: Hose clamp questions, 70-72

DCM = DiChroMate Those clamps are dipped in dichromate to give them a yellow cast to indicate their size.

I can't say as I have ever seen a 1 1/2-inch DCM clamp on a Corvette, but Wittek made clamps for all the big three car manufacturers and manufactures other than GM may have had different specifications. Even other car lines within GM may have had different specifications. Wittek made many millions of clamps and a manufacturing error is not outside the realm of possibility. Since you have seen one, it would be possible to see others. Remember, they weren't making Corvettes or tower clamps for us to judge years later.

If I had access to my 1970 I could address your #1 question, but that won't happen until next week, and maybe not even then.

[Mike E.]

Re: Hose clamp questions, 70-72

Terry,
Thanks. That helps!

[Mark E.]

Re: Hose clamp questions, 70-72

Just to confuse, my car has a set of reproduction Witek clamps-

- The 3/4" heater hose has 1 1/16" tower clamps
- The PCV inlet hose has 1 1/8" tower clamps

I don't know if this is TFP but they fit well.

[Mike E.]

Re: Hose clamp questions, 70-72

Mark, yours are not tfp at all.