TD Glow heads

There is a single fin glow head for the GTP nissan, stocker, and Indy cars.

FYI,
About 10 years ago, I bought 5 each Texaco 5 fin heads from Dan Sitter (California Dan) on eBay at a decent ( Now) price.
When I received the 5 fin heads, they all had the knurled ring on top and all 5 had the 1702 high compression combustion chamber!!
Dan had about 50 to start with but sold all in about one day.
Since he had access to all things Cox, I have wondered if they were factory experimental and he accidentally sold them without noticing the difference.
Have also wondered if they were especially for Texaco events at higher elevation events ?
If anyone knows please advise..
Steve....

Interesting thread.

I did not know about those car plugs! Sure hope I can recall all that in the future.

So if I got this right there was both a 5 fin and single fin high compression plug.

I'll have to look for the ones I ordered from Bernie, as that was some time ago.

Bill

Just looked in my stash and found the only plugs I have from Bernie are knurled! My befuddled brain lied to me again!

smooth_bill wrote:Cox International in Canada had plugs with no Knurling for a while. Apparently they didn't go over too well, so later batches resumed the knurling,

All hi-compression plugs have the Trumpet shaped combustion chamber. Photos of both examples are on the Internet, and in some model forums.

CLARIFICATION

We have been manufacturing the TD glow heads without a knurl for about a decade; omitting the knurl for cost reasons (would have added a buck to the retail price). Not only did they go over very well but they were actually amongst our very top sellers.

It is just that we sold out of them and new production was delayed due to the China manufacturing shutdown. Our competitor Matt had previously gotten some made with the knurl and we borrowed a few hundred to tie us over.

Now that China is back at work again, we have ordered 1,000 units and should have them here early May (again, without the knurl).