I see lots of different subtypes of Holley 94 carbs out there. The one on Elvis is maybe not original because the air horn doesn't fit the oil bath air cleaner well - I have to shim it about 1/16".

Can't read any type on my carb except "Ford". Should this have a 7RT or 8BA or what's the difference or best one for a 239 or 255 flattie?

-Scott

Elvis '53 F100 with Mercury 8CM heads on I don't know what block, but it runs...

 

There are all different types, and the later model 2110's are phsically similar. There should be a cast-in number on the side near the venturi with the throttle diameter (a true 94 is 13/16"). There were variations for different air cleaners, as you've seen.

Here's a good summary (but only of car applications)

 

Why so many different subtypes and what are the differences? What would have shipped on a '53 F100

 

I don't know if this helps but I just picked up 2 NOS 94's in the original boxes
They are labelled as "FORD TRUCK 1948-52, F1 Through F6" and are part No. 8RT-9510-F

Stephen

 

I have seen 8RT's mentioned as truck carbs, but didn't know what years. Thanks.

-Scott

 

8RT-xxxx is the generic part number for anything V8 truck in 48-52. The engine is an 8RT in a truck, an 8BA in a car.

The differences can include a governor, a hand throttle provision, different jetting, different throttle linkage, etc. Different power valve calibrations. If you look closely some of them have the air horn (where the air cleaner attaches) in slightly different places relative to the throttle plates. The later 2110's use a different choke intermediate lever because their air horn is almost 3/4" further forward. The 2110's also have 1-1/16" throttle bores and are therefore almost 15% larger capacity -- a quick hop up bolt-on. (That's what I'm running).

If your engine is truly a Merc, it wouldn't have come with a 94 at all (as far as I know anyway, I'm not a Merc guy). It should have had a "teapot" style carb, a huge affair with the bowls mounted above the throttle plates in a separate assembly. I forget the model designation but there's no mistaking it, and it's a 4-bolt carb. You for sure have a Ford intake if you've got a 94 carb on it without an adapter.

 

Then I surely have a Ford 3 bolt intake manifold which makes dropping the pan to check the stroke even more important as compression is only about 75 lbs. per cylinder. Maybe the previous owner thought he would hop it up by putting on the Mercury heads...

-Scott