The adrenaline shakes take over in your left leg as you probe your subconscious for the list of things that will keep your car off the guardrail. In your right hand is the shifter connected to a reverse-manual valvebody in the automatic. With 800 pounds showing on the brake-pressure gauge, you floor the gas pedal, letting loose the dogs and bumping off the rev limiter in the water box. With a slow count to three, you release the button on the line-lock and roll to the starting line. With your foot on the floor you sidestep the brake pedal and head for the rev limiter before pulling the shifter down for the one, two, three. You pass the stripe at 145 mph and lift. The engine freewheels, muting all but the sound of the pebbles bouncing in the wheeltubs.
Our ’71 Dodge Demon project is going to make neck-snapping power courtesy of a couple of Comp Turbos plugged into our eBay Hemi. We briefly considered a modern overdrive, a stick, and even ogled a Lenco on eBay until fabricator Grant Peterson ended that conversation. He was correct. The right move for our Dodge Demon was to stick with the classics on this throwback to the ’70s and bolt in a 727 TorqueFlite Performance Automatic. The only car that came close to beating the primer ’55 in the movie Two Lane Blacktop had one, and that’s good enough for us.
The 727 first appeared in 1962 as the “early model” that had a large-spline input shaft and was sometimes operated with a push-button shifter. The transmission in our Dodge Demon was built for us by Performance Automatic (PA) in Gaithersburg, Maryland, and is based on the later ’71 to ’78 model. It has a fine-spline input shaft and, when the Performance Automatic transmission is properly prepared, is suitable for 600 to 700 hp abuse at race car weight and can handle a 10- to 11-second street door-slammer, no problem. Just don’t use the one designed for a lockup converter. The transmission continued in production in various forms until 1991, after which its design was absorbed into newer models.
The Street Smart System
PA Street Smart System kits are designed to make the transmission upgrade for muscle cars and street rods easy. The kits include the transmission, a custom converter, all performance parts, a deep chrome pan with a drain, and a dipstick with a tube.
All burnouts should be started in Second gear, then the transmission should be shifted to Third as soon as the tires start to spin. When you roll out of the water box, lift off the gas. Never blip the throttle. The idea is to avoid shifting with huge sticky tires spinning at a high speed by simply lifting off the gas as you roll out of the box in High gear. Shifting as the tires begin to grip or dragging out of the box in First will rip the overrunning clutch out of the case. Ask us how we know.
How To Shift It
This transmission uses a full-manual-reverse valvebody. That means the governor and kick-down are out of the equation. When you move the shift lever, it shifts. As a safety mechanism, the engine is allowed to freewheel during deceleration in First gear. If you should shift into First at high speed and you are not on the gas, you won’t pull the engine down or lock the wheels. The reverse pattern also pulls down and away from Neutral and Reverse so you don’t accidentally engage them.
Dodge Demon Parts List
|727 small-block Chrysler
|727 big-block Chrysler
|10-inch Pro Launch torque converter
Andrews Powder Coating; Chatsworth, CA; 818/700-1030; PowderCoater.com
BBK Performance Products; Corona, CA; 909/735-2400; BBKPerformance.com
Chris Alston’s Chassisworks; Sacramento, CA; 888/388-0297; CAChassisWorks.com
Circle City Hot Rods; Orange, CA; 714/279-0400; CircleCityHotRods.com
Coker Tire; Chattanooga, TN; 423/265-6368; CokerTire.com
Comp Cams; Memphis, TN; 800/999-0853; CompCams.com
Comp Turbo; San Dimas, CA; 909/599-5757; CompTurbo.com
DIY AutoTune/MegaSquirt; Suwanee, GA; DIYAutoTune.com
eBay Motors; Motors.eBay.com
Glasstek; Naperville, IL; 630/978-9897; Glasstek.com
Holley Performance Products; Bowling Green, KY; 800/HOLLEY-1; Holley.com
IC Engine Works; San Antonio, TX; 512/858-2232; ICEngineworks.com
Lincoln Electric; Cleveland, OH; 216/481-8100; LincolnElectric.com
Miller Electric Mfg. Co.; Appleton, WI; 920/735-4141; MillerWelds.com
Mopar Performance; Mopar.com/performance
MSD Performance; El Paso, TX; 915/855-7123; MSDIgnition.com
Performance Automatic; Gaithersburg, MD; 301/963-8078; PerformanceAutomatic.com
Speedway Motors; Lincoln, NE; SpeedwayMotors.com
Stainless Works; Chagrin Falls, OR; 800/878-3635; StainlessWorks.net
Street & Performance; Mena, AR; 479/394-5711; HotRodLane.cc
Summit Racing Equipment; Akron, OH; 800/230-3030; SummitRacing.com
Transmission Specialties Inc.; Aston, PA; 610/485-9110; Transmission-Specialties.com
Turbosmart USA; Rancho Cucamonga, CA; 909/476-2570; TurboSmartOnline.com
Wilwood Engineering; Camarillo, CA; 805/388-1188; Wilwood.com
The 727 will fit into most Mopar models without this much surgery. In this case, we moved
Before the build, PA stripped the cores down to be cleaned and inspected. Because the tran
This is the high-gear drum. It contains the clutches and steels that are upgraded for addi
This is the rear drum, that, despite its name, holds the First, Second, and Third gear clu
This is the rear drum partially assembled. Here you can see high-temperature Kolene coatin
This is the reverse-manual valvebody. It has CNC-machined fluid passages that change the p
This is the output shaft. The bearing at the end is replaced as needed.
The overrunning clutch (aka sprag) is normally splined and pressed into the case. Performa
The main pump body gets a new bushing and pump gears.
In this photo, the original band is lying flat on the bench, and the replacement Raybestos
With everything back in the case, you can see (left to right) the rear band that holds the
You want the highest-capacity trans cooler that will fit the car. The guys at Performance
This is Tyrone Bryant, putting the finishing touches on the 727 before it is shipped. PA b
To keep the new transmission alive, you need to keep it cool and shift it correctly in the
The converter is a heavy-duty 10-inch Pro Launch from Transmission Specialties. It has a b