calculating CFM on carbs

S2261

Well-known member
I have a 1978 200 in my 1961 Comet. Currently I am running an Autolite 1100. This spring I want to spend some time fine tuning things. How do I calculate the CFM on a carb? I have an assortment of Holley, and autolite carbs to choose from. I want to find the best match for my engine. Right now I am looking for the most reliable application. I have some performance mods in the works. This is a parts gathering year. The 1100 seems to be doing the trick. It runs well and all that. I just wonder if it could run better. I am commited to running the Load O Matic dizzy.
 
The 'Ford Falcon 6 Perf. Handbook' has a pretty handy section on carbs listing CFM ,on many carbs of many styles. My copy is 8 months old and looks like it is 10 years old from use.
I am commited to running the Load O Matic dizzy.
I am surprised at a 78 200 with a Load-o-matic. I would have thought that the hole in the block was too big and that the oil pump set-up would be mismatched.

Most of my driving (62 falcon)--up to half throttle-- is on a 78 200 with a 2100 autolite 108 2 bbl on a clifford adapter with DS2 and the response is excellant. After half throttle the 2 weber 1bbl's kick in. but even before i hooked them up the 108 would support some very good hi rpm's (5500+) also.
Good Luck Dan
 
I also have the FFPH. I see where it explains CFM recommendations for engines. Did not see anything about the Holley 1908 CFM. I'll look again. The engine was rebuilt last year. It was set up to run with the old style LOM Dizzy. I like the look, stealthy. I have pertronix ignition instead of points. It runs pretty good right now. My goal is to eventually go with the tri carb set up. I was wondering about the CFM on the holley vs the 1100 I have on now. I have a few Holley 1908's, 1909,s to choose from. I have a couple glass bowls. I like that look. If I can make the Holley 1908 with glass bowl work I'll be happy. The car is 1961 Comet. I am trying to stay with the stock appearance for now.
 
If you are set up for the load-a-matic and have some old Holleys laying around a tri-power setup should make good power.
Your right it (FFPH) doesn't show cfm on the 1908's But if you're running an 1100 that's compatible with LOM dizzy you are going to be fairly close, and compatible with the LOM. Stick one on there and see how it feels.
And if you use 3 you are going to be in good shape. Lower cfm is beneficial in low rpm situations and more cfm in hi rev which is why the whole progressive linkage tri-power works so good.
3 glass bowled holley's are a real class look.
 
Thanks for the info. Ever since I saw a pic with the 3 holley's w/glass bowl covers, I knew that's what I wanted.
 
Howdy Back S2261:

Sorry for the CFM omission on the early Holleys. It will be corrected in a future edition.

FYI the CFMs on the 1904, 1908 and 1909s were fairly close to standard at 130 in a 144 engine applicaton and 150 with the 170 engines. The exception is that the #1909 on a '62 with the 144 engine was down rated to 125 CFM according to the Pony Guide book.

The #1904 was used in a variety of Ford cars on either the 215 ci six or the later 223 engines starting in 1952. It was used on the '60 Falcons with a manual choke. The Comets got an auto choke.

The model #1908 was similar to the #1904 and used in the '61

In '62 the Comets and Meteors got the #1909 carbs. The only factory applications other then '62 144 and 170 engines was on some '63 Ramblers.

All use the SCV and are compatible with a LoM distributor. In a 3x1 application you will want to plug the SCV in the two secondary carbs and just use the center one for a vacuum signal to the distributor.

The Pony Carburetor, Inc book "Ford Carburetor Guide" would be a good investment for you in this endevoer. Also, quality rebuild kits offer good illustrations, specs and instructions.

I agree with you that a well done 3x1 with glass bowl Holley's is one of the coolest intakes possible. Good luck.

Adios, David
 
All you need now is a 60-61 dual action fuel pump with the glass sediment bowl at the bottom. :lol:
 
...and a wayward rock! I do have the dual action pump. You know what they say about vacuum wipers, they suck. Thank God for Rain-X.
 
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