After building a 65 Falcon with my dad and my son I decided on many details I wanted in my own build project. We invested most of our time and effort in the motor, it was great! : The only thing I was never happy with was the transmission: The car only had 58K miles on it when we got it. It had been in a barn in Lakeland, Florida for 8 years. We pulled the little C4 and cleaned it and took it to a trans builder recommended by a relative to go through it and make it right. The shop did a good job. They made upgrades to the oiling system and changed some servos and installed a shift kit. It was $600 for a complete rebuild with a warranty. I was happy with the quality of the build and the way the trans shifted. But they did not add any extra gears...that little Falcon should have been much better to drive in several ways. It would have been awesome fun with a T5. The Falcon was light and we think our rebuild increased gross HP from a factory 105 to about 125-130 HP. But even with a 2.79:1 (highway) rear gear, that C4 made the 170 scream at 4500 rpm's at 70 mph. That's not danger level for the Thriftpower Six, they can regularly spin up to 6500-7000 without coming apart, but you just don't want to drive it very far at that noise level. The biggest failing of most custom and hot rod cars is their fuel consumption. You don't want to drive far or often because of how much it eats. I am building a Grand Touring car and it needs good range on a tank of gas. I have a 1970 Maverick, you know, the one with the stupid little 16 gallon gas tank you can't upgrade. I am putting in a V8...not a good combination for range. I have to have an overdrive transmission. After lots of reading on this forum, Ford Muscle forum, and many other sources, and talking to a trans builder with over 40 years experience I have developed a plan. I am going to have an AOD/4R70W hybrid built. Here's my logic: 1. To match my 99 5.0 motor I need a SBF bell housing. This means AOD case. 2.The AOD and the 4R70W have interchangeable gear sets. The 4R70W has stouter gears, and lower first and second gears for heavier vehicles like F150-250, Expeditions and Explorers and also high performance use behind the 32V motors in Cobras and Lincolns. I will use the 4R70W gear set. This will be good for durability behind my slightly better than stock 5.0 motor, and give better acceleration than the AOD. 3. I want no electronics other than the stereo, back up camera, and sat-nav. I'm not paying big dollars for a transmission controller and still face the challenge of wiring. It has to be a "dumb" transmission. So we use the Lokar AOD TV cable and AOD mechanical/vacuum controls. 4. When I talked to the trans builder, he said I should also use the stamped steel drum from the 4R instead of the cast iron drum used in the AOD for less rotating inertial mass, better throttle response, less parasitic power loss and maybe a little bump in gas mileage. 5. I got an unopened Trans-Go AOD HP shift kit for it on craigslist for $20 and Poppa Randy got the AOD cross member from Frank months ago. ( Thanks Frank!) We also have a new AOD-5.0 flexplate. My transmission guy told me he would build the custom trans and give me his normal warranty for $500 if I brought him 2 working transmissions. I got my AOD from a wrecked 91 Mustang GT 5.0 with 94K miles for $250 Here it is next to the C4 we pulled out of the Mav. I got a working 4R70W from a 93 Mark VIII with 88K for $175 miles. It was a parts car a guy was stripping to build a mustang. What I would still like to know: 1. Can I use the .67 O.D. from the AOD? or do I have to use the 4R's .73 O.D.? ( are the overdrives interchangeable?) I Think my Maverick could get low 20's mpg cruising at 70 with a .67 OD X 3.00:1 rear gears = final drive ratio of 2.01:1 It's probably even way off that because of the huge 17" wheels will turn much slower than the 14's that were on the 75 I got the rear end from. 2. I have the early body car with the smaller trans tunnel. Will we have to cut the floor and trans tunnel, or just "massage" it some with a big hammer and torch?
Something is wrong if you have a 2:79 rear gear and your engine is truly turning at 4,500 RPM at 70 MPH. Depending on tire diameter it should be operating at about 2,300 - 2,500 RPM maximum.
Very true, with 2200 stall converter, 3:00 gear & 255/60/15 tires my Comet turns approx 2800 RPM at 70... I'd like to get that down, and have more gear(IE 3:50 out back), still have the Supercoupe AOD that I used in Bird... I think the O/D depends on the gear set, I'm guessing you'll have the 4R70W ratios... But it's of no concern, running 25.5" tall 225/60/16, I've gotten 26 mpg in the AOD T-Bird with Trick Flow headed & cammed 5.0 & 3.73 gears(admittedly that was running around 60 mph)... RPM are in the 2500-2600 range at 70 mph...
That engine really needed a T-5 manual transmission and some 3.80 gears, it doesn't matter because that car is gone. The point is this: I want engine rpm's in my Maverick to be like my 96 Ram 5.2 this is what I mean: This is a steady cruise on a very flat stretch of interstate. It looked like that most of the way to Illinois and back to Florida to get my doors. In my truck with a 5.2 Magnum (similar in size and power to my Maverick's 5.0) Automatic and 3.50 rear gears this kind of cruise is good for about 14 mpg average over a 2200 mile trip. My truck with me in it and out of gas weighs 4760 on the county garbage scales after its empty. I'm 225 lbs. Automobile catalog lists my 70 Maverick base model 200 Auto at 2533 lbs. http://www.automobile-catalog.com/c...rick_2-door_sedan_200_six_cruise-o-matic.html I am adding an estimated 250 lbs of stuff to the car with sound deadening, power disc brakes, and other stuff. That's nearly a ton of weight difference for a similar sized engine with similar transmission gearing. My Maverick's 3.00:1 rear will slow down the rpm's even more than the trucks 3.50 rear. The highway fuel mileage should be excellent for a hot rod. It may hit 25 mpg in long flat stretches. I think it will average high teens in town...depending on my foot and mood!
I had the same thoughts. The Falcon probably had some smalltires but 4500 stills seems way high for that ratio. A higher stall convertor could be an issue but not a 2000, at 4500 you're way past it's "lock up" point.
Alan's 65 Falcon had a Cruise-O-Matic C4 Green dot. It did not have a lock up converter. You got 3 speeds, that's all, no overdrive, no TC lock-up. It was a major upgrade from the Cruise-O-Matic 2 speeds available in the 64 and earlier models. The lock up converter did not see widespread use till the late 70's. My 70 Maverick did not have a lock-up converter either. Here are some pics of my 70 Maverick C4 non lock-up next to a 91 AOD lock-up converter. the C4 converter is the smaller gray one. We searched unsuccessfully for a lock-up converter for his Falcon when we had it out for the rebuild just to get the rpm's down and the mileage up. A 125 hp 6 cylinder automatic in something as light as a Falcon (2562 lbs.) should have gotten mid to upper 20's gas mileage, but his Falcon averaged around 16-17 mpg in mixed driving for about a year.
Still no Cruse-O-Matic, C4, Two Speed auto, etc I ever saw spun the engine to 4500 RPM @ 70 unless maybe it was in 2nd gear... Unless it was setup for race only, the converter will play a small part but gear ratios were all same reguardless of engine... Either you had a transmission issue or you tach was set to 4cyl position... A AOD converter doesn't really lock up, transmission has a inner shaft that is splined into the front hub of converter... When clutch in trans engages the converter is basically bypassed and is in direct drive, O/D occurs in the trans not converter...
I'm with the rest, 4500 at 70 tells me that sumbitch was slipping like crazy or the tach was off. Could be the tach was set for a 4 cylinder.
my dyno sheet for the 306 I had came in at 93 MPH at 11,800 RPM. when I questioned the numbers as maybe set to a 4 or 6 cyl, the Guy told me " the dyno humbles a lot of people" .I told him I wasn't humbled, I was impressed that it would turn almost 12K. I paid the $100 and left... 3:55 - 255x60x15s
