For a while now, I've been researching data and spec details for this carburetor model Ford/Holley 1904, also known for featuring "glass fuel bowl". The carburetor appears to have been used in multitude of mostly(?) 6-cylinder Ford passenger and truck applications between about 1952 to 1959, maybe later. I've discovered there are several sub-models with variety of detail and technical differences ranging from different throttle bore sizes to chokes and linkage designs, etc. Are there any members here with in-depth knowledge and willingness to offer me advise and guidance in these variations ? I'm tasked to build or recreate a (historic ?) engine (+ running gear) that originally (supposedly) featured multi-carb set-up with these atop of custom, hand fabricated intake manifold. The original engine was built by a rather famous SoCal Hot Rod engine builder/tuner over 60 years ago, but went missing along with the vehicle fairly soon after. The subject vehicle or what's left of it was discovered (without running gear) several years ago and information known today is quite scarce, but enough for the owner to pursue restoration of it. I've actually already sourced and built the basic (replacement) engine and planning to start, run & test it on the dyno some time later this fall or winter, but initially with readily available intake and carburation. Also, I'm not at liberty to share more details about the engine or the vehicle at this time. Thank you for understanding.
You could try a search.....something like this. https://www.jalopyjournal.com/forum/search/118386404/?q=Holley+1904&o=relevance&c[node]=5 Roger
OK, a bit of information to help your research: I have listed 155 different versions of the Holley model 1904 carburetor. These were used on both 4 and 6 cylinder engines from 144 to 305 CID in the year span of 1952 through 1974. Companies using these carbs were: AMC, Chrysler, Ford passenger, Ford truck, Edsel, GMC, IHC, Mercury, Towmotor, and White. You have already found that there are different throttle bores; there are also different internal venturii sizes to accommodate the various different engine sizes. If a chart of throttle bore sizes and venturi sizes exist, I am unaware of it. This information may be obtained, one carburetor at a time, from the Holley Master Parts Manuals. Somewhere about 1959, someone in the government decided the glass bowls were unsafe, and Holley started using diecast bowls. Additionally, the commercial rebuilders would replace the glass bowl on any carb they rebuilt with the diecast bowl. As so often happens when the government becomes involved, the "Law of Unintended Consequences" comes into play. The Holley diecast castings warp (in this case the body). Since the edge of the bowl is vertical, they leak. The glass bowls didn't warp (glass doesn't warp), but the new diecast bowls also warp; so the carbs with the diecast bowls warp twice as fast and leak more than the ones with the glass bowls. Unintended consequences!!! Glass bowls today do bring a premium because so many of them were thrown away. The warped castings CAN be straightened; using a series of forms with heat and pressure. The normal selection guideline of starting with ALL carbs being identical by identification number applies. If you are unaware of how to identify the type 1904: Position the carburetor such that you can read the word "Holley" on the bowl. The fuel inlet screws into a raised boss on your left. Clean the side of the boss you can see, and you will find TINY STAMPED letters and numbers to identify the carburetor. More understanding of the circuitry of the 1904 may be found in the Holley Service books. Not my choice for a multi-carb set-up, so I will wish you good luck! Jon.
Just an fyi, the glass bowls also fit other models of Holley carbs. I have some that I plan to put on a Holley 1920 dual carb setup that I have on a slant six. The 1920's were used on a host of different cars, mostly six cylinders. So if you find the 1904's not suitable you might be able to use 1920's or if you are just going on the fact that photos show the glass bowls, they might not be 1904's.
While the bowl will fit the type 1920; the type 1920 first appeared in 1960. As the OP is attempting to replicate an engine built at least before 1958 (at least 60 years ago), the type 1920 may not be applicable because of the replication requirement. Jon.
TTR - will be happy to speak with you if you call 573-392-7378 (9-4 Mon-Tues central time). However, I am NOT going to make any recommendations as to which ones to use, for several very good reasons. Will be happy to try to answer general questions on these, but not specific ones. I will make a comment for you to consider: GUESSING that this was some form of race car, and the family wants it recreated, which is great. The issue becomes "what is the intended use of the engine"? These carbs are probably going to give problems. Actually, the owner is probably going to give problems. SPECULATING that the application is going to be car shows, maybe parades, and at least one trip down the race track or one dyno pull (got to prove what it will do!). The design of these carbs makes them DIFFICULT to be used in an all-around multi-carb environment. It can be done, if either cost is no object (and I mean NO OBJECT) or you own an automobile machine shop, are a carburetor guru, and don't count your time. So, if I guessed right on the application, you have TWO UNIQUE choices without selling the farm. (1) You plug the economizer circuit completely, and jet the carbs for wide open throttle (racing). Under these conditions, carbs will be pig-rich at anything except WOT to the extend of fouling plugs, blowing black smoke, even stalling. (2) You plug the economizer circuit completely, and jet the carbs for normal driving. The very first WOT detonates sufficiently to damage the engine!!! THE TWO CHOICES ARE MUTUALLY EXCLUSIVE! Of course, you can do BOTH 1 and 2 above, and have the owner switch out the carb set prior to that WOT blast. As before, I wish you good luck. Jon
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