1966 C4/6 transmission swap to AOD

[edventure]

Hey Guys,

Just bought a 66 T-Bird 390 Hard Top in real nice condition and almost fully loaded in one of my fav color combos Medium Blue over Wimbledon White top. . Factory a/c car with power windows and full safety convenience panel. Wish it had power seats and power antenna but I can live with all the other options which to me are the most important. Besides I guess I can always hunt for those 2 items and add them on but its probably now worth the headache.

The engine has been replaced with another 390 so it is not original matching #'s so with that being said, I am definitely going to mod it to make it more of a daily driver/streetable.

I have a long list of things I'd like to do but one of the first is to swap out the C4 3 speed for an AOD transmission. I want to be able to cruise on the hwy going 80 with low rpm's and for better mileage, performance etc. I know a few owners that have gone this direction and even spoke with a guy out in Cali who did this to his 66. He said it was a ton of work and nota direct swap, but well worth it. Any thoughts on this or of a shop that is reputable, and can tackle this? All feedback is welcome. Thanks!

Ed

66 T-Bird

This page contains affiliate links for which I may be compensated. As an eBay Partner, and Amazon Associate I may be compensated if you make a purchase at no cost to you.

 

[biddle]

You can omit the make and/or model of your car from future subjects to shorten it since we are an all Ford Thunderbird site. I edited it for you.

 

[jack-in-sac]

Hey Guys,

Just bought a 66 T-Bird 390 Hard Top in real nice condition and almost fully loaded in one of my fav color combos Medium Blue over Wimbledon White top. . Factory a/c car with power windows and full safety convenience panel. Wish it had power seats and power antenna but I can live with all the other options which to me are the most important. Besides I guess I can always hunt for those 2 items and add them on but its probably now worth the headache.

The engine has been replaced with another 390 so it is not original matching #'s so with that being said, I am definitely going to mod it to make it more of a daily driver/streetable.

I have a long list of things I'd like to do but one of the first is to swap out the C4 3 speed for an AOD transmission. I want to be able to cruise on the hwy going 80 with low rpm's and for better mileage, performance etc. I know a few owners that have gone this direction and even spoke with a guy out in Cali who did this to his 66. He said it was a ton of work and nota direct swap, but well worth it. Any thoughts on this or of a shop that is reputable, and can tackle this? All feedback is welcome. Thanks!

Ed

66 T-Bird

Actually your transmission is not a C4. C4s are not found behind FE engines. At that point in time it Believe the transmission would be a cruise-o-matic. An AOD is not necessarily a strong transmission. An overdrive automatic transmission source could be a later model but not anywhere during the 60s or 70s. The AOD is from 1980 and forward until the AODe. An AOD can adapted to an FE. If using behind an FE an aftermarket performance transmission builder would be a decent source.

 

[edventure]

Actually your transmission is not a C4. C4s are not found behind FE engines. At that point in time it Believe the transmission would be a cruise-o-matic. An AOD is not necessarily a strong transmission. An overdrive automatic transmission source could be a later model but not anywhere during the 60s or 70s. The AOD is from 1980 and forward until the AODe. An AOD can adapted to an FE. If using behind an FE an aftermarket performance transmission builder would be a decent source.

I thought the cruise-o-matic and the c4 were one in the same? Either way, Monster Transmissions makes an upgraded heavy duty AOD ( and AODE) transmission with an FE adapter kit. Problem is its almost $5k for the entire kit and not to mention it's not an easy bolt on swap. I spoke with a guy out in California that did this swap into his 66 and he had to change reverse the motor mounts, change the driveshaft although I know that's not a big of a deal, and also trim some a part of the tranny itself to make it fit in the tunnel. He did mention it " fits" , but barely. Overall, he said it was well worth it. I may go in the same direction.

 

[jack-in-sac]

I thought the cruise-o-matic and the c4 were one in the same? Either way, Monster Transmissions makes an upgraded heavy duty AOD ( and AODE) transmission with an FE adapter kit. Problem is its almost $5k for the entire kit and not to mention it's not an easy bolt on swap. I spoke with a guy out in California that did this swap into his 66 and he had to change reverse the motor mounts, change the driveshaft although I know that's not a big of a deal, and also trim some a part of the tranny itself to make it fit in the tunnel. He did mention it " fits" , but barely. Overall, he said it was well worth it. I may go in the same direction.

At that price for a changeover to an AOD or AODe it may be cheaper to go with a Gear Vendors overdrive since you have to alter the driveshaft with the AOD swap. good luck, J.

 

[edventure]

At that price for a changeover to an AOD or AODe it may be cheaper to go with a Gear Vendors overdrive since you have to alter the driveshaft with the AOD swap. good luck, J.

It is cheaper but an AOD is lowers the rpm's significantly compared to a Gear vendor's unit. Besides I want it to behave like an automatic more so than having to shift it myself.

 

[edventure]

It's been a while since I've updated my status on this project. As of now, after 2 +years I finally have it back. It's safe to say that its under the "trials" part of the build.

I'll go over what went right, and what didn't.

The head swap decision proved to be very costly and time consuming as there are many variables when swapping the heads.

All I wanted to do was have the bird have more pep in her step but I don't think its worth the time and money as the gains are not very noticeable but that's also on me since the parts I chose were for a mild upgrade. I went ahead and ordered Edelbrock aluminum heads (Edelbrock Performer RPM Cylinder Heads 60069). I was told by edelbrock that it was a direct swap from stock heads. Couldn't be further from the truth. I had to get adjustable rocker arms Harland Sharp Heavy-Duty Roller Rockers S4006NBK, bigger custom valve covers, oh and the brake system, had to yank the whole thing out bc the valve covers were not clearing due to the spacing of the brake booster. I ended up installing a universal electric brake system kit from ABS Power Brake inc. I also upgraded the cam to an Edelbrock Performer Plus Cam #2106. Lastly, it has an Edelbrock aluminum intake manifold as well along with the Concept One front driveline with new power steering pump and ac compressor. AC is not operable and that is the next major undertaking. I'm in florida and its 90+ for 6 months of the year.

All in all, it was a total nightmare because a lot of the components not being compatible with one another. These birds don't like to be touched it seems.

As far as the tranny swap for the AOD, although it was a big project, it was done right and went smoothly besides the linkage adjustments needed. As of now she cruises at 70mph with 2150rpms. We pulled the rear end from an open 3.00 to a posi 3.70 and it has made a considerable difference in acceleration.

Speaking of cruising, the faster I'm going the more unpredictable the steering is, especially after 65+mph. They rebuilt the steering box, and pittman arm, and I have coilvers in the front but the play in the steering makes it unstable at higher speeds. Need to sort this out bc its really hampering the highway drivability.

The Holley Terminator EFI setup has been mostly great. I'm averaging 9.8 gallons on the highway which is exactly where I thought it would be. It used to get me about 5. The venting of the gas fumes has been the only major issue with it and we're trying to sort that out now.

One last thing to add, Do not buy from Monster Transmissions! They suck!. I spent 6k on the heavy duty AOD and FE adapter and their torque converter was leaking when installed. My mechanic plugged it with a weld and I called them to inform them and they immediately voided my warranty. Do not buy from them as there are much better options out there.

 

[PAT: OLD MAN/VETERAN]

It's been a while since I've updated my status on this project. As of now, after 2 +years I finally have it back. It's safe to say that its under the "trials" part of the build.

I'll go over what went right, and what didn't.

The head swap decision proved to be very costly and time consuming as there are many variables when swapping the heads.

All I wanted to do was have the bird have more pep in her step but I don't think its worth the time and money as the gains are not very noticeable but that's also on me since the parts I chose were for a mild upgrade. I went ahead and ordered Edelbrock aluminum heads (Edelbrock Performer RPM Cylinder Heads 60069). I was told by edelbrock that it was a direct swap from stock heads. Couldn't be further from the truth. I had to get adjustable rocker arms Harland Sharp Heavy-Duty Roller Rockers S4006NBK, bigger custom valve covers, oh and the brake system, had to yank the whole thing out bc the valve covers were not clearing due to the spacing of the brake booster. I ended up installing a universal electric brake system kit from ABS Power Brake inc. I also upgraded the cam to an Edelbrock Performer Plus Cam #2106. Lastly, it has an Edelbrock aluminum intake manifold as well along with the Concept One front driveline with new power steering pump and ac compressor. AC is not operable and that is the next major undertaking. I'm in florida and its 90+ for 6 months of the year.

All in all, it was a total nightmare because a lot of the components not being compatible with one another. These birds don't like to be touched it seems.

As far as the tranny swap for the AOD, although it was a big project, it was done right and went smoothly besides the linkage adjustments needed. As of now she cruises at 70mph with 2150rpms. We pulled the rear end from an open 3.00 to a posi 3.70 and it has made a considerable difference in acceleration.

Speaking of cruising, the faster I'm going the more unpredictable the steering is, especially after 65+mph. They rebuilt the steering box, and pittman arm, and I have coilvers in the front but the play in the steering makes it unstable at higher speeds. Need to sort this out bc its really hampering the highway drivability.

The Holley Terminator EFI setup has been mostly great. I'm averaging 9.8 gallons on the highway which is exactly where I thought it would be. It used to get me about 5. The venting of the gas fumes has been the only major issue with it and we're trying to sort that out now.

One last thing to add, Do not buy from Monster Transmissions! They suck!. I spent 6k on the heavy duty AOD and FE adapter and their torque converter was leaking when installed. My mechanic plugged it with a weld and I called them to inform them and they immediately voided my warranty. Do not buy from them as there are much better options out there.

Wow Thanks, I am on the same road but a few months (or years) behind. Trying to figure out how to adapt a 4R70W or E to my 63 with 390FE. I am ready to take my engine to a local rebuilder, to have a "mild" full roller Comp cam with all the goodies and install Edelbrock Performer RPM heads and intake manifold. I am going to install the Sniper2 EFI using their master kit and figure out how to run the return line. Thanks for the heads up on Monster Transmissions as I was considering them. I also have the Ford 9 inch open rear end with 3.00 gears and was wondering what I need to do to convert i to a 3.50 "posi." Does anyone think it would be worth it to get one from a wrecking yard and rebuild it or opt for a "performance" one from one of the providers such as speedway, JEGS or one of the others. As I am 80+ and have had some pretty serious health issues since I got the 'Bird about 8 years ago and haven't been able to work on as I would like. i am now trying to complete it and give it to my son who has expressed an interest in having but is not even close to being a "big car nut or have any mechanical skills.) I have been building and racing cars and motorcycles since I was a kid but the military and life got in the way to a whole lot on the newer cars. Retired and can only work when I have help and "feel up to it" so now I am using the computer to assist me in finding what I need and checking out what does and does not work. So thanks any help would be appreciated on doing the upgrade from Cruise-o-matic to 4R70W/E

 

[edventure]

Wow Thanks, I am on the same road but a few months (or years) behind. Trying to figure out how to adapt a 4R70W or E to my 63 with 390FE. I am ready to take my engine to a local rebuilder, to have a "mild" full roller Comp cam with all the goodies and install Edelbrock Performer RPM heads and intake manifold. I am going to install the Sniper2 EFI using their master kit and figure out how to run the return line. Thanks for the heads up on Monster Transmissions as I was considering them. I also have the Ford 9 inch open rear end with 3.00 gears and was wondering what I need to do to convert i to a 3.50 "posi." Does anyone think it would be worth it to get one from a wrecking yard and rebuild it or opt for a "performance" one from one of the providers such as speedway, JEGS or one of the others. As I am 80+ and have had some pretty serious health issues since I got the 'Bird about 8 years ago and haven't been able to work on as I would like. i am now trying to complete it and give it to my son who has expressed an interest in having but is not even close to being a "big car nut or have any mechanical skills.) I have been building and racing cars and motorcycles since I was a kid but the military and life got in the way to a whole lot on the newer cars. Retired and can only work when I have help and "feel up to it" so now I am using the computer to assist me in finding what I need and checking out what does and does not work. So thanks any help would be appreciated on doing the upgrade from Cruise-o-matic to 4R70W/E

Hey there oldman/ Veteran,

First off, thank you for your service! I'll point out some things you must be aware of before embarking on modernizing or resto-modding your T-bird.

The head swap, make sure you get adjustable rocker arms and dont get the edelbrock one's because I was told they are prone to failure. Get the harland sharps. I don't know if you're getting the same edelbrock aluminum heads I got. Also, i would highly recommend you upgrade your stock oil pump to a high volume oil pump ( melling). This should be available in most auto parts stores, also get the oil filter adapter from Tbird Parts as it will come in handy. Also remember that you will need bigger valve covers when swapping heads, and those new valve covers will interfere with your brake booster, so you will have to either yank the entire brake system and replace it with a universal electric kit, or get very creative with your shock towers and current brake booster, which I dont recommend. If you're doing the head swap you might as well upgrade the cam too.

One more thing lol, do not get a sniper. The sniper has the ECU in the engine bay, and you will more than likely have issues with interference from the distributor. It's recommended you get the terminator with its standalone CPU that you can place inside the cabin ( mine is by the passenger footwell).

Now, on to the tranny swap. Sit down for this, lol. You're going to have to get a custom transmission mount done and obviously a new drive shaft. Get new u-joints while you're at it, and the linkage is going to be a pain in the ass but its doable, it might be easier in a bullet bird but I am not sure. The shop ran into problems with the linkage. I think you are choosing the right tranny 4R70W vs the AOD that I got. I have not had any issues with it and in hindshight I should have gotten the 4R70W bc it can hold a lot more power.

You absolutely have to change the rear end, and do a high quality change don't cheap out on it. With the new tranny and gearing, it will bog down with the original gearing especially in stop and go traffic. I did a posi 3.70 rear and my gearing is perfect now. It has good low end acceleration and on highway cruising at 70 mph I'm at barely 2100 rpms. 75 mph and its right under 2300 rpms. You should be able to get an FE adapter plate with your tranny when you order it. Make sure the torque converter is setup properly before you buy.

If you have any other questions or anything else just let me know. Good luck!

Ed Gil

66 390 Hardtop