1968 Trim Rings

[Gregory M.]

I have been told that 1968 trim rings are different then other years due to clip placement and that this difference can be detected when installed on a rim. If so, will the incorrect trim ring result in a point deduction during flight judging?

How rare are they and how much should I expect to pay for a nice set when I find them? Thanks

GM

[Joe L.]

Re: 1968 Trim Rings

Greg-----

The 1968 trim rings were the same as those used for 1969-82, even though the wheels were different. I've heard this story about the clip placement being different and I don't understand it, at all. The trim rings available today are the same part number as those originally supplied with the cars. The placement of the clips (as well as other aspects of configuration of the rings) might have changed over the years of manufacture of the trim rings, but I doubt very seriously that those supplied in SERVICE "once-upon-a-time" were any different than those supplied with the cars at about the same period of time.

[Gregory M.]

Re: 1968 Trim Rings

I checked my technical manual in the interim and it does make reference to 1968 having the clip placement in line with the valve stem hole while 1969-1982 are not in line with the hole...why I do not know...I remember an article in the driveline not to long ago and have to go check my back issues...

If the rim was 7 inches in 1968 rather than 8 inches isn't the ring shallow-er?

Does anyone know if it is detectable while mounted and therefore a point deduction during judging?

If there is a 1968 only trim ring what should I expect to pay for them?

GM

[Gregory M.]

Re: 1968 Trim Rings

My memory served me right...for those interested there is a comprehensive examination of trim rings in the Summer 2007 Restorer at page 38.

So the questions remains...how much do they go for?

GM

[Wayne W.]

Re: 1968 Trim Rings

The 68 is not as deep in the front, but the 69 up trim ring fits. There is just more gap between the wheel and the ring on the later models.

[Joe L.]

Re: 1968 Trim Rings

Greg-----

The trim ring was the same. There is just "less wheel showing" on 1968 wheels than on 69-82 since the trim ring covers more of the wheel rim.

The clip position is easily detectable; no doubt about that. Assuming that the clip position was uniformly located throughout the 1968 model run, I suppose that would make the 1968 rings unique. However, since the part number of the rings did not change, that would mean that a change in the clip position would had to have been specified on the specifications for the ring after 1968. In other words, if the original specifications for the ring called for the placement of one of the clips at the valve stem hole, for that to change after 1968 would have required a specification change.

The thing I do not understand is why the position of the clips would have made any difference for 1968 or, even, any other model year. I could understand why it might be important that the clips be spaced roughly 90 degrees apart, but I don't understand why it would ever been necessary to specify that one of the clips had to be at the valve stem hole position. Or, if it was thought necessary for 1968 for whatever reason, why would that have become unimportant after 1968?

[Terry M.]

Re: 1968 Trim Rings

Actually 1968 to 1972, and some time beyond, trim rings are for the most part the same. The placement of the clips (near the valve stem hole, and every 90* thereafter) is the same for all five years, and somewhat beyond. At some point in the mid to later 1970s the clip placement changed -- probably due to manufacturing techniques changing. The location of the clips is judged in 1968-1972 NCRS judging. The point deduction is not more than a couple of points out of 4500, however. One can lose as many judging points for scratched and dented trim rings, and will certainly lose more points for trim rings with the full-circumference grippers.

There are other more subtle differences in the manufacture of trim rings over the years, and I am not up on all of them. The size of the valve stem hole is one of them I do know about, but I don't know the details of that variance. I don't believe there is anything that makes 1968 trim rings any different than 1969 or 1970 trim rings, unless it is in the mind of the seller. Of course if someone has a set of old trim rings to sell it is to their advantage to convince a prospective buyer that what is for sale is a unique item, not to be passed buy.

[Gregory M.]

Re: 1968 Trim Rings

According to the article (Summer 2007 NCRS Restorer at page 38) There is no difference between 1968-74 rings which are called 1st design. The 1974-82 are called second design. The difference between the two designs are subtle changes in the clips and construction, none of which are detectable with the trim ring installed. All of the 1968-82 have the four clips at 90 degrees with one lining up with the valve stem hole. The over the parts counter replacements from the 1980s are the 3rd design and have the four clips with one that does not line up with the hole.

The significance of this is that the 1968-82 will ALL look identical when installed, 4 clips with one lining up with the valve stem hole, and should NOT result in any point deduction during NCRS flight judging.

FYI, the valve stem holes from 1968-82 are all the same as well...an oval that is flattened at both ends. Only the 1967 valve stem hole is a true oval.

Anal retenetive, the lot of us

GM

[Terry M.]

Re: 1968 Trim Rings

Sounds to me like you have answered your own question 12-hours after you posted it. Good work.