holly 4 barrel carb linkage

T

tjaybo

Member
I am putting a Mummert intake and holly carb on my 1955 club sedan with a fordo trans. I would like to know what others have done with carb and trans shifter and kickdown linkage.
Thanks :confused:
 
You might want to consider going AOD. The Ford-O-Matic is a Borg Warner design that uses a throttle linkage control system to operate the throttle valve in the transmission it appears to be a kick down but it's a lot more than that. There was no vacuum modulation until the 60s so it was all done mechanically to get the ATF pressure levels needed to properly control the transmission throughout the range of operation. The AOD being a distant relation to the early Ford-O-Matic, uses a TV cable off the throttle linkage to essentially do the same thing as the earlier TV rod like your car has and it's easier to adjust.

There may be a way to make a TV cable work on the early transmissions but I've never seen it happen yet on this forum. If the original linkage will work on the new manifold & carb then a person could go that route. A C4 trans change would also put control back to the vacuum modulator but kick down is another situation. It's all been done before I'm sure.

You may also have to ditch the load-o-matic distributor and find a 57 or later distributor. The load-o-matic depends on the venturi vacuum set up from the original carb. Later carbs won't have that feature.
 
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Why can't you just use the original throttle bell crank and put it on the Mummert intake ? That intake has a provision for the original bell crank to mount. Then see if the bell crank is higher or lower than the original intake manifold, and adjust the kick down rod length accordingly.


Sal
 
What I said above only applies if your original bell crank is for a 4 barrel engine.
Two barrel engines had the linkage on the back of the intake. Mummert's intake won't have anything to mount it on.


Sal
 
originally the car was a 2 barrel.
I had the fordo rebuilt at a cost of about $1300 so I would rather not have to do a conversion to an AOD.
I have replaced the distributor with a 57 compatible electronic.
My hope was to find someone who has gone down this route and can tell me how to solve some of the isssues.
Does an original 4 barrel set up work if I could find one?
Thanks
 
If you get a bell crank from a '55 or '56 four barrel Y-Block V8, it will bolt on and you will have to figure out the correct length for the kick down rod. I've seen bell cranks on EBAY before. An EBAY vendor (natolibird) Felix Natoli sells bell cranks for '57 engines. He may have something that works for you. I'm pretty sure he makes them (reproductions).


Sal
 
A 57 assembly will bolt on as well, but you will have to change your hardware that mates the kickdown rod to the assembly. 55 and 56 had an L shaped piece that you could use to adjust the height/length of the rod. 57's look more like a clevis but it too has a threaded boss that can increase/decrease your length on the kick down rod.
 
I know I had a heck of a time converting my linkages when I went from a 2 bbbl to a Offy tri-power with Holley 94s. It was a ton of work, trial and error, etc. Works great now.

If you are looking for a kit, forget it. Everyone's answer is change the transmission. I say forget that. Just remember, that linkage rod that goes down to the trans is nothing more than what we woild equate to a throttle position switch on later cars. Oh say 84 Cadillace, that era. If the car shift HARD, late, or you have to let off the throttle to let it shift, then adjust the rod shorter. It can be done, you just need patience. Also a Holley 4 bbl carb that has the ford side shaft is desirable
 
I might add one other thing. Don't think you will take this to a hotrod shop, or a restoration shop and get this done. If they take the work in it will not be right. This is soooo time consuming that they will not make any money on the project. And well you know....
 
There is a procedure that is required to properly set up the linkage. It may be in your shop manual, but i doubt it. It is not there for a 56. You would have to get the Fordo manual or a Motor's book - that is where I found it.
 
paul2748 said:
There is a procedure that is required to properly set up the linkage. It may be in your shop manual, ...
Click to expand...
The 4bbl V8 throttle linkage bellcrank and transmission throttle valve 'kickdown' rod adjustment procedure is on page 2-89 in the '57 Shop Manual. Just did this last week.

I'm using a '57 intake, carb and throttle bellcrank on a '55 block in a '55 Bird with Fordomatic. The '55 TV / kickdown rod is a bit short. The adjustment piece at the top is very close to the end. If I need more adjustment length I've been told(?) the '57 rod is longer.
.
 
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Check with Lokar shift systems "did I spell that correct?) all the magic is done down
on the transmission not a bellcrank on the manifold by a rod. We did this on a 1956 and
it doesn't care the engine or what carburetor and its adjustable too by a cable like later
vehicles.....
 
The setup procedure is in my manual, but for me it did not help. I was going to a setup where I had to modify the bellcrank just to allow me enough leverage to push the throttle open.

paul2748 said:
There is a procedure that is required to properly set up the linkage. It may be in your shop manual, but i doubt it. It is not there for a 56. You would have to get the Fordo manual or a Motor's book - that is where I found it.
Click to expand...
 
big job said:
Check with Lokar shift systems "did I spell that correct?) all the magic is done down
on the transmission not a bellcrank on the manifold by a rod. We did this on a 1956 and
it doesn't care the engine or what carburetor and its adjustable too by a cable like later
vehicles.....
Click to expand...

Are you referring to the throttle valve aka TV cable? The old Ford-O & Merc-O-Matic transmissions of the 50s will not function without the connection to the throttle since there is no vacuum control like the 62 & later transmissions have. The much later Ford AOD transmission of the 80s to early 90s uses a cable connected to the throttle and it has to be properly adjusted for basic function as well unless it's one of the later electric models. The AOD conversions have been done but I haven't found a cable conversion for the Ford-O-Matic to take the place of the TV rod system. It might be doable but I can't find any info from Locar.

A lot of what I've found out there is for conversion to the C4 transmission. This requires a kick down cable as well as a throttle cable but it does away with the bellcrank set up on the Y-block and gives a person a real 3-speed auto but it has no low gear selection. Since it starts out in low anyway, it's not a real big hurdle to get over.
 
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A LOKAR cable conversion would be ideal as it will take the guessing and slop of old linkages out of the equation.

The throttle rod would be retained but the TV rod and hardware would be eliminated. The TV pressure would not vary as acceleration increase and/or decreases as the engine moves with torque.

Now on a dedicated restoration, I would prefer the OEM setup.

LOKAR has enough universal parts to design your own application as there would be little demand for LOKAR to merit design/production costs.
 
The AOD was designed for a cable pull but the Ford-O-Matic wasn't. My concern is that the amount of movement may not be equal on a Ford-O versus an AOD.

When setting up an AOD, all a person has to do is set the pressure at 35 psi with the cable set up in tension and the throttle at idle and that's it. The amount of cable pull through the range will be set. With the the Ford-O-Matic, will it have the same amount of pull through the range, will it be less, or will it not have enough. A person needs to be sure that it has the correct amount of pressure throughout the range of operation. It might take a custom lever with the proper length to get it right. They have custom levers for the AODs but not the Ford-O-Matics.
 
The F/M is set the same manner as the later AOD, with a pressure gauge.

The first issue AOD's had hard linkage and then went into cable.
 
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