66 Tire Valve Stem Length

[Dave K.]

66 JM specifies valve stem length to be 2 -2 1/8 in. which will result in the valve cap just protruding through the hubcap and may require removal of the hub cap to remove the valve cap and add air to the tire. I was docked at the Charlotte Regional last year for valve stems of 2 1/2 in. that had the valve cap completely out of the hubcap.

Before I cut the old valve stems and install a shorter stem, I'd like opinions on the correct length for a 66.

Regards,
Dave K.
33108

[Page C.]

Re: 66 Tire Valve Stem Length

Hi Dave,
Checked an original 1966 7-75/15 BFG 660 Silvertown spare tire that has never been mounted on a car. Still has some of the nubs on the thread. The valve stem measures 2 inches from the rim to the end of the threads where a dome type cap screws on.
Regards,
Page Campbell

[Dave K.]

Re: 66 Tire Valve Stem Length

Hi Dave,
Checked an original 1966 7-75/15 BFG 660 Silvertown spare tire that has never been mounted on a car. Still has some of the nubs on the thread. The valve stem measures 2 inches from the rim to the end of the threads where a dome type cap screws on.
Regards,
Page Campbell

Thanks Page.

Dave K.

[Wayne M.]

Re: 66 Tire Valve Stem Length

Dave -- I agree with Page's measure. Just checked 2 rims (a '65 and '66) and, using a dial depth micrometer, they measure 2.06 - 2.08" from the surface of the rim at the base of the stem, to the top of the brass threaded part. When a 1965 hubcap is installed, just the brass protrudes, plus about 1/16" of the rubber. If the tire is off, you will see TR-418 moulded into the inner seat of the stem base.

Much the same issue with '65s. The judging manual says stems should be 1_3/8" long, "and protrude from a hole in the hubcap". Trouble is, the brass is way down in the hole. You'd need tweezers to get the cap.

[Rob M.]

Re: 66 Tire Valve Stem Length

Is the 1 3/8 length for KO wheels? That is what I used and it seems about right for airing up the tires.

[Wayne M.]

Re: 66 Tire Valve Stem Length

Is the 1 3/8 length for KO wheels? That is what I used and it seems about right for airing up the tires.

-----------------
Rob -- 1_3/8 is what the '65 TIM&JG calls for on KO's, and this may be correct. Just measured stems on a set of '66s I have (original wheels but not the stems) @ 1.14" (to top of brass), and 1.25" on a set of repro KO's. Both LOOK reasonable, with no problem accessing the cap.

It's just the 1_3/8" for '65 steel wheels and wheel covers that I question.

[Noel K.]

Re: 66 Tire Valve Stem Length

i bought replacement (new) hubcaps for my '65 to be judged with original K-H wheels. I read the JG and it called for 1 3/8" valve stems. They DON'T protrude out of my "repro" hubcaps.

I was docked points for the incorrect valve stem length. I believe the valve stems for the steel wheeled cars w/hubcaps have to be longer but I still don't know what the correct length is.

Hope there's an expert out there to help us all.

Noel

[Michael M.]

Re: 66 Tire Valve Stem Length

The correct valve stem for mid-years with steel wheels is the TR-418 Schrader. On the under side of the valve stem the original said TR-418 Schrader USA as per Nolan Adams page 265. I have a bunch of these and 2" is the length that is on the outside of the rim.

[Michael H.]

Re: 66 Tire Valve Stem Length

Dave -- I agree with Page's measure. Just checked 2 rims (a '65 and '66) and, using a dial depth micrometer, they measure 2.06 - 2.08" from the surface of the rim at the base of the stem, to the top of the brass threaded part. When a 1965 hubcap is installed, just the brass protrudes, plus about 1/16" of the rubber. If the tire is off, you will see TR-418 moulded into the inner seat of the stem base.

Much the same issue with '65s. The judging manual says stems should be 1_3/8" long, "and protrude from a hole in the hubcap". Trouble is, the brass is way down in the hole. You'd need tweezers to get the cap.

Wayne, if you scroll down on this DB page to a post called "Chevrolet Corvette Advertising 1965", you get to see a shot of the wheel and hub cap on the red 65 when Parnel Roberts points out the new side louvers. I stopped action and looked at the valve stem. It appears to be flush with the face of the hub cap, or slightly above.
I also have an original wheel and stem and it's the same 2.ox dim you posted.

Or, better yet, here's the link.

http://www.youtube.com/watch?v=L3HvkrYIIwo