The Ford Barn

mgm60 · 05-20-2023, 09:56 PM

Installing a Columbia 2 Speed in my 36 which has dual Stromberg 97s. Have the carb adapter plate with vacuum port but what do I do with the second carb to keep them at the same height? Use a spacer or use a second adapter plate? If I use a second adapter plate should I just block the vacuum port or plumb it inline with the first? Not a lot of room between the two carbs on my Sharp intake to be able to connect the second vacuum port if its needed.

Brian · 05-20-2023, 10:57 PM

any of your proposed above situations would work.

Cool Kat with Hot Car · 05-21-2023, 12:49 AM

I didn't want to poke a hole in my Eddie Meyer intake so I just drilled through the center of one of the studs holding the carb. to the intake. I was afraid it would be too restrictive a source for vacuum but it has been working for 30 + years now.

Terry,OH · 05-21-2023, 06:08 AM

Do both of the Carbs, have to be at the same height? Check your vacuum gauge and I believe you will find about 15 which should work to shift the Columbia but is getting low. So make sure the Columbia is in gear when you shift.

Bored&Stroked · 05-21-2023, 07:55 AM

Vacuum Tanks and one-way valves: Do any of you guys add an extra vacuum reservoir/tank with a one-way "flapper" valve to store more vacuum?

Brian · 05-21-2023, 01:26 PM

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On my 35, equipped with twin carbs like original poster, I have included a non return valve in the vacuum line to columbia control. Dunno if it's needed, but figured it can't hurt.

blucar · 05-21-2023, 02:42 PM

A little bit of trying to re-invent the wheel..
The engine in my '36 is a 59AB that is highly modified, with dual 97's on a Offy Super manifold. The rear axle under my car is a 47-48 Columbia with '47-48 electric over vacuum controls.
The vacuum source for my Columbia is via a port in the manifold below the rear carb. I installed a tee fitting into the the manifold, attached the vacuum line to the wipers on one side of the tee and the vacuum line to the electric solenoid OD valve on the other side of the tee.
This system has been working since 1955 with no difficulties.
I have no idea how many inches of vacuum the engine has, I figure, if it ain't broken, don't fix it.

petehoovie · 05-21-2023, 03:35 PM

Quote:

Originally Posted by blucar

A little bit of trying to re-invent the wheel..
The engine in my '36 is a 59AB that is highly modified, with dual 97's on a Offy Super manifold. The rear axle under my car is a 47-48 Columbia with '47-48 electric over vacuum controls.
The vacuum source for my Columbia is via a port in the manifold below the rear carb. I installed a tee fitting into the the manifold, attached the vacuum line to the wipers on one side of the tee and the vacuum line to the electric solenoid OD valve on the other side of the tee.
This system has been working since 1955 with no difficulties.
I have no idea how many inches of vacuum the engine has, I figure, if it ain't broken, don't fix it.

Terry,OH · 05-22-2023, 06:43 AM

When you shift the Columbia the dash control vents to atmosphere one side of the shift canister and applies vacuum to the other side. The dash valve reverses this action to shift to the opposite ratio so be careful where you install a one way valve. I don't think any are necessary. As mentioned previous the reduced vacuum when using dual carburetors is usually substantial enough to shift.

Bored&Stroked · 05-22-2023, 06:45 AM

Quote:

Originally Posted by Terry,OH

When you shift the Columbia the dash control vents to atmosphere one side of the shift canister and applies vacuum to the other side. The dash valve reverses this action to shift to the opposite ratio so be careful where you install a one way valve. I don't think any are necessary. As mentioned previous the reduced vacuum when using dual carburetors is usually substantial enough to shift.

Good point! One would have to ensure that any sort of vacuum storage would be between the engine and the controller valve - such that all the control sees is more/better vacuum.

solidaxle · 05-22-2023, 12:09 PM

Hell, Even with a blower, mine pulls in and out without hesitation. The outlet is between the carburetor bases and the rotors. You have to let off the gas like all Columbia's to have the vacuum rise.

05-20-2023, 09:56 PM	#1
mgm60 Member Join Date: Oct 2020 Location: Parker, Colorado Posts: 63	Columbia 2 Speed - Vacuum Installing a Columbia 2 Speed in my 36 which has dual Stromberg 97s. Have the carb adapter plate with vacuum port but what do I do with the second carb to keep them at the same height? Use a spacer or use a second adapter plate? If I use a second adapter plate should I just block the vacuum port or plumb it inline with the first? Not a lot of room between the two carbs on my Sharp intake to be able to connect the second vacuum port if its needed.

05-20-2023, 10:57 PM	#2
Brian Senior Member Join Date: May 2010 Location: Masterton, New Zealand Posts: 3,838	Re: Columbia 2 Speed - Vacuum any of your proposed above situations would work. __________________ Unfortunately, two half wits don't make a whole wit!

05-21-2023, 12:49 AM	#3
Cool Kat with Hot Car Senior Member Join Date: Jul 2010 Location: NorCal Posts: 256	Re: Columbia 2 Speed - Vacuum I didn't want to poke a hole in my Eddie Meyer intake so I just drilled through the center of one of the studs holding the carb. to the intake. I was afraid it would be too restrictive a source for vacuum but it has been working for 30 + years now.

05-21-2023, 06:08 AM	#4
Terry,OH Senior Member Join Date: May 2010 Posts: 4,765	Re: Columbia 2 Speed - Vacuum Do both of the Carbs, have to be at the same height? Check your vacuum gauge and I believe you will find about 15 which should work to shift the Columbia but is getting low. So make sure the Columbia is in gear when you shift.

05-21-2023, 07:55 AM	#5
Bored&Stroked Senior Member Join Date: Jan 2011 Location: Central Ohio Posts: 5,079	Re: Columbia 2 Speed - Vacuum Vacuum Tanks and one-way valves: Do any of you guys add an extra vacuum reservoir/tank with a one-way "flapper" valve to store more vacuum?

05-21-2023, 01:26 PM	#6
Brian Senior Member Join Date: May 2010 Location: Masterton, New Zealand Posts: 3,838	Re: Columbia 2 Speed - Vacuum Sponsored Links (Register now to hide all advertisements) On my 35, equipped with twin carbs like original poster, I have included a non return valve in the vacuum line to columbia control. Dunno if it's needed, but figured it can't hurt. __________________ Unfortunately, two half wits don't make a whole wit!

05-22-2023, 06:43 AM	#9
Terry,OH Senior Member Join Date: May 2010 Posts: 4,765	Re: Columbia 2 Speed - Vacuum When you shift the Columbia the dash control vents to atmosphere one side of the shift canister and applies vacuum to the other side. The dash valve reverses this action to shift to the opposite ratio so be careful where you install a one way valve. I don't think any are necessary. As mentioned previous the reduced vacuum when using dual carburetors is usually substantial enough to shift.

05-22-2023, 12:09 PM	#11
solidaxle Senior Member Join Date: Mar 2011 Location: upstate NY Posts: 478	Re: Columbia 2 Speed - Vacuum Hell, Even with a blower, mine pulls in and out without hesitation. The outlet is between the carburetor bases and the rotors. You have to let off the gas like all Columbia's to have the vacuum rise.