Ok real quick bottom line,,it seems the 97's and 48 are more a less the same carb,LZ and 81 a bit different,but what about parts from column A & B. A 48, EE1 base with an 81 97 LZ mid ,97 top ?? You kinda get the idea.I would guess the jets make the difference and maybe with the best of each carb you could make a hybred??lol What fits what and how much can you get away with?
All bolt patterns same. Venturi sizes .81 .97 1 1/32 small throttle bores on 81, same sizes 97 and 48 small pump on 81 jets 036...045...048 standard base lever on 81-97 has two balls for pump, 48 has one--frequently found interchanged upper casting 81-97 has little sprinloaded bullet that holds choke open fulley, lever has extra surface to meet this, wrong lever will jam on bullet... Jets differ due to lower sensitivity of bigger venturis... in 1936, all three carbs were offered on 85 HP Fords, and note the huge jet difference! 81 was designed for 60, and used on the earliest V8 60's sold by Ford GB in Europe only 1935-36. The carb got her before the engine did--Ford offered it as a service part for commercial vehicles used only at low speeds in cities, as the 48 with its big venturis was a pig running all the time on its idle circuit at low speeds. The 48 was the standard carb early on, then the 97 was offered as a service part also for economy--it worked well at all speeds, and early on became the standard carb for later '36 Fords.
LZ is I think 1". There were two versions, all of mine are the same, and I have not researched the difference...I would guess there is a later one with 97 type levers. Both I have are like 48's.
Hello..Just some more info..B.L. is right on..The 81 has a EE 7/8 on the base, the 97 and 48 have EE 1.. Now..Bodies..Some 97 bodies have notches in the venturies to fit over the dump tubes of the Bat Wing "V" bases..( Some of the Bat Wing bases, the tubes where cut off so non notched bodies would fit)..I believe that the Bat Wing with the dump tubes are the best bases......The two balls on the throttle shaft for the pump rod are for Summer and Winter....S..W.. Interchangable..everything EXCEPT.. 81 throttle plates and pump plunger.. I think that does it.. Duane.. ps..some made in South Bend and Elmira..
I just learned that some Strombergs made in '49-50 & after as replacements had an extra idle circuit or something. When using these in multiple carb setups, you will likely run over rich & require much more tuning to get right...
I just got my first one of these...short, slanted brass pipe sticking out of vertical idle/off idle passage right above normaloff-idle, looks like idle air bleed is smaller than normal. Haven't gotten idle jets out yet. Ford bulletin says idle and off idle run the car til "18-22 MPH" before main takes over, main til 76 MPH and power apertures come in...in other words, lots of day to day driving doesn't even involve the main jets. Probably more than that on multi-carb setups... I assume purpose of this mod was to make the mixture more sensitive to airflow and less arbitrary, using pressure drop from air passing over tube end in a way analgous to the venturi. This over-dependence on the idle circuit is why Ford offered first the 97 and then the 81 as carbs for 85's run just at low speed, I believe.
Hello...My understanding is the new 97s have this type of manegment system in the bases.. I want to know why Vintage Speed sells secondary bases without the idle holes..I know that I've gotten several that have been plugged, in the base and the body where the idle jets go. I guess I should put one together and bench test it with a primary.. Duane..
Duane, I believe we've talked many times about why it's not a good idea to plug up the idle circuits. LOL Matt
I think if I were to experiment with plugging, I would start by just turning in the screws and keep the intermediate feed operational!
Hello...I'm not going to ruin a base or body to try this..I have a few with the Idle system plugged, in the base and body. Duane..
The Jalopy Journal
