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ramos291
09-05-2015, 07:49 PM
Hello fellow Tbird lovers.
I am in the process of installing a new Edelbrock 600 CFM carb with electric choke on my 61 390. The fit seems to be good and so far it runs will. My question is for those that have swapped out their carb for a similar carb. Does the Dash pot and mecanisum get removed and not used any more. If so, what is done with the two HOT wires that were connected to it? Also, what have to done with the vacuum line that was also connected to it?

jopizz
09-05-2015, 08:21 PM
What dash pot are you referring to. The original Ford carburetor had a manual dash pot that had no wires or vacuum connected to it. Is it something that was added afterward. Do you have a picture of it.

John

ramos291
09-06-2015, 11:02 AM
I called this the dash pot but I do not think that is the correct name for it. Anyway, I dont know if it should be removed and so forth.
11715What dash pot are you referring to. The original Ford carburetor had a manual dash pot that had no wires or vacuum connected to it. Is it something that was added afterward. Do you have a picture of it.

John

jopizz
09-06-2015, 11:08 AM
That's something that was added on later. It's not factory. Just trace the wires back and remove them and plug wherever the vacuum line was connected to at the motor.

John

Alan H. Tast, AIA
09-06-2015, 08:39 PM
WRONG, jopizz! What's pictured is very much factory - it's used '61-only on T-birds with air conditioning. It cut power to the A/C compressor clutch when there's a drop in vacuum, such as when accelerating or dropping into passing gear. In '62-later models this switch was moved inside the car. As for adapting the switch to a car with an Edelbrock carb, all I can suggest at this point is to get a copy of the '61 T-bird shop manual and the '61 T-bird Electrical Assembly Manual, study the air conditioning system diagrams/schematics to see how it works, and wire/fabricate/assemble accordingly.

jopizz
09-06-2015, 09:02 PM
Alan,

Thanks for correcting me. I had never seen that before and I don't remember seeing it in the shop manual or the parts manual. I'll have to look again.

John

ramos291
09-06-2015, 09:09 PM
WRONG, jopizz! What's pictured is very much factory - it's used '61-only on T-birds with air conditioning. It cut power to the A/C compressor clutch when there's a drop in vacuum, such as when accelerating or dropping into passing gear. In '62-later models this switch was moved inside the car. As for adapting the switch to a car with an Edelbrock carb, all I can suggest at this point is to get a copy of the '61 T-bird shop manual and the '61 T-bird Electrical Assembly Manual, study the air conditioning system diagrams/schematics to see how it works, and wire/fabricate/assemble accordingly.

Thank you Alan for the information and tip.

ramos291
09-06-2015, 09:11 PM
Alan,

Thanks for correcting me. I had never seen that before and I don't remember seeing it in the shop manual or the parts manual. I'll have to look again.

John
Thank you jopizz for your input Sir.

jopizz
09-07-2015, 12:42 PM
I finally found a picture in the electrical manual of the fast idle control. I'm sure it can be made to work on the Edelbrock carburetor but I would try it without it first. Seems it was done away with after 1961. Alan mentioned that it cut power to the clutch on acceleration or change in vacuum. Since it was only used for one year I imagine it didn't work that well.

John

Alan H. Tast, AIA
09-07-2015, 12:59 PM
I finally found a picture in the electrical manual of the fast idle control. I'm sure it can be made to work on the Edelbrock carburetor but I would try it without it first. Seems it was done away with after 1961. Alan mentioned that it cut power to the clutch on acceleration or change in vacuum. Since it was only used for one year I imagine it didn't work that well.

John

It wasn't done away with - please re-read my previous post. The switch was revised to get rid of the mechanical kick-down linkage component. It was relocated and designed so that it was placed inside the car. On '62-'63s it was placed on top of the evaporator case and still had a vacuum port as well as the two electrical connections. When vacuum dropped, it allowed the contacts in the switch to open, cutting power to the A/C clutch to allow more power for acceleration.

If someone doesn't care whether their engine bogs down with the air on when they hit the go-pedal, then this switch can probably be abandoned, but I am not sure what the "feel" of doing that is like. I do know that when going up steep hills with the AC on, having the AC cut out as the engine labors is noticeable in terms of the AC not pushing cold air into the cabin.

simplyconnected
09-07-2015, 01:28 PM
Today, we use a WOT (wide open throttle) Switch, mounted right on the throttle. It energizes a small relay which in turn shuts off a few things like:
The AC compressor,
The alternator (or generator field),
Anything else electric that is pulling power.

This allows full HP to go to the rear wheels. As soon as your foot lifts off the floor, all electrical functions resume as normal. - Dave

jopizz
09-07-2015, 01:37 PM
You didn't read my post either. I said I would try it without it first. I didn't say to do away with it. If it bogs down with the air on then reconnect it. If not then don't use it. It looks like the way it's designed he can keep the vacuum connected to it and it will still shut off the compressor when going up a hill without having it connected to the carburetor. I imagine it was connected to the carburetor to boost the idle with the A/C on. Similar to what today's cars do by computer. That's probably why it's referred to as a "fast idle device".

John

Alan H. Tast, AIA
09-07-2015, 06:44 PM
Touche', John :-)

ramos291
09-07-2015, 07:49 PM
I finally found a picture in the electrical manual of the fast idle control. I'm sure it can be made to work on the Edelbrock carburetor but I would try it without it first. Seems it was done away with after 1961. Alan mentioned that it cut power to the clutch on acceleration or change in vacuum. Since it was only used for one year I imagine it didn't work that well.

John
Ah, very good picture John THANK YOU. So far I have basically plugged the vacuum from the fast idle control and covered up the electrical connectors and am just running the Edelbrock carb with out them. My A/C is not currently on the car but some day I plan to get it going.

ramos291
09-07-2015, 08:05 PM
Today, we use a WOT (wide open throttle) Switch, mounted right on the throttle. It energizes a small relay which in turn shuts off a few things like:
The AC compressor,
The alternator (or generator field),
Anything else electric that is pulling power.

This allows full HP to go to the rear wheels. As soon as your foot lifts off the floor, all electrical functions resume as normal. - Dave
Interesting information Dave. Thank you for sharing. You say "today", is this something you have come up with?

ramos291
09-07-2015, 08:11 PM
You didn't read my post either. I said I would try it without it first. I didn't say to do away with it. If it bogs down with the air on then reconnect it. If not then don't use it. It looks like the way it's designed he can keep the vacuum connected to it and it will still shut off the compressor when going up a hill without having it connected to the carburetor. I imagine it was connected to the carburetor to boost the idle with the A/C on. Similar to what today's cars do by computer. That's probably why it's referred to as a "fast idle device".

John
That is a good point about trying it first and see the response. I will keep the device around incase i need to put it back on the car once I get the AC going again.
Thanks for the information Sir.

jopizz
09-07-2015, 08:36 PM
I would definitely keep it. Even if you don't use it I'm sure there's someone out there that's looking for one for a concours correct car. I imagine they are pretty rare since they were only used for about a year and a half. Probably a lot of them were taken off and thrown away. I've had lots of Thunderbirds with A/C and I've never even seen one.

John

simplyconnected
09-08-2015, 08:22 AM
...You say "today", is this something you have come up with?I'm not that smart. WOT switches are mounted on just about every Electronic Fuel Injected throttle body out there. They indicate, your pedal is on the floor, you need as much HP as possible right now and 'get me off the tracks!'

Back in the early '60s, 'conservation' was never high on the list. If you added a device that used HP, you simply got a bigger engine. Pretty soon, family cars had engines that hovered around 390-400 cubic inches. I NEVER thought I'd see a Cadillac with a six cylinder engine but my uncle has one.

Engineers started to re-evaluate power needed for each 'thing' to do its job. For instance, your mechanical fan. Mechanical engineers HATE the electrical guys. For this reason, de-clutching fans were introduced. After further investigation, nobody could substantiate the need to run a fan at all when the engine is cold. Electric fans only turn on when the radiator is hot. Sometimes months pass before my daily driver's fan turns on during Detroit winters. I still see trucks with a radiator cover all zipped-up because he can't stop his fan.

Just about all functions are controlled by electricity now, including the transmission shifting. The result is HUGE efficiency gains with much better allocation of power from a small engine. Grand Marquis and Crown Vic, before they were dropped, had a Romeo engine that was shy of 300 cubes. Yep, Police Interceptors, too. Back in the day they were 427s. - Dave