Cox 1702 glow head

My QZ came with one, and thats a mid-late 60s engine.

i have several on my golden bees that i hopped up.

The knurling on the top of the head indicates a high-compression configuration as found on TD .049 and .051 engines.

So,

I guess the real proof would be if they were indeed trumpet shaped as opposed to the standard lower compression versions.

Would it be possible that Cox just changed the head design and used the same part# for the TD?

Ron:

By a purely UNSCIENTIC comparison, when "flipping" one of my BW's and TD .049's, a distinct difference in the compression felt and heard.

The BW has a standard Cox glo in place while the TD .049 has the "knurled" version.

SuperDave wrote:Ron:

By a purely UNSCIENTIC comparison, when "flipping" one of my BW's and TD .049's, a distinct difference in the compression felt and heard.

The BW has a standard Cox glo in place while the TD .049 has the "knurled" version.

I agree Dave, the TD has a little more tooth when hand flipped. Physically they are different as one is conical and one is trumpet shaped.

Bernie says they are the real deal 3 ring 1702's. I learned something new today.....

Yes, I have seen a couple of the 3-fin high compression ones over the years.

The only real way to tell for sure is to look at the chamber shape. The high compression ones are the trumpet shape. These usually had the knurled head over the years for identification purposes. Then again, our new production ones are high compression, trumpet shape, but do not have the knurl on the top.

In the same respect, I have a couple of 09 glow heads that have the knurling on the top, but are not the high compression trumpet head when looking at the chamber. The are just the regular Medallion 09 glow heads. Obviously a production error, but they exist.

Basically, the easiest was to tell is ignore the outside and look at the chamber. If it is the trumpet shape, its high compression.

Matt

I have some pics of the head compared to a regular standard head on my site. http://sites.google.com/site/coxenginecollection/quiet-zone I think you can still click on the images to see them larger.

[quote="jsesere"]Here's a 3 fin 1702 I ran accross. I'm not sure I have ever seen one. I thought all 1702's were 2 fins.


Hi Joe & Gang,

The 1702 hicomp head came out with the Tee Dee in '61 and remained pretty much the same until I believe mid sevenites ('75-'77) when one fin was removed, probably to retain more heat or cut cost?

Mark