The Stovebolt Site Forums The Shop Area Engine Shop Distributor compatibily question

My 1948 3100 Thriftmaster has a 1954 passenger car 235 engine in it (swapped by the original owner years ago). Truck was also converted to 12v.

I would like to attempt the "stock appearing" electronic ignition upgrade explained over at Deve's Technical Network's website, but I would like to do this with a spare distributor and not the original one that's in my 235 engine now. Which means I will need to find another one to alter.

Are all 216/235 distributors for this era of truck (and the later 50's era passenger car 235s) the same?

Deve's conversion requires a "tall" distributor. I KNOW '52 and earlier distributors were "short". I THINK '54 and later were "tall". I don't know about '53.

That said, I am running a Deve's HEI in my '52 GMC with a '54 Chevy tall distributor. I have hidden the HEI module inside the no longer needed (because I have a 10si alternator) stock voltage regulator box.

My "How I did it" was posted over here.

10 years later and it is still working well.

The "short VS tall" issue coincides with the switch from 6 volt to 12 volt ignition systems in mid-year 1955. The taller cap and rotor was needed to avoid "flashover" of the spark from the rotor tip to the distributor housing in case a plug wire open circuited or a wire fell off the plug. The 12 volt coil was capable of producing much higher secondary voltage than the 6V system it replaced. Electronic ignition systems produce approximately three times more open circuit secondary voltage than a 12v point system. As long as the plug wires are in good shape and they fit snugly onto the plug terminals, either style can be used. Take that "tech net" information with a big grain of salt- - - - -most of it is plaigarized from other sources, with no attribution, including the information on the electronic distributor conversion.
Jerry

My blog post about distributors lists when tall caps started. https://chev235guy.blogspot.com/search/label/Distributor%20part%20numbers%20by%20year?m=0

Hi Sinister,
If you aren't going to lose sleep over a non-stock looking distributor, you can see how I convert these on the cheap. They work very well on the 235s and you can use the coil-in-cap type or the external coil setup. The guts are copies of GM parts and you can use GM parts for replacements of any of them, too. I've been using one of these I adapted in 1997 and have not had a problem with it. You can find them on eBay with red, blue or black dist caps.

https://tinyurl.com/kkmzjdb5