If one could describe the mechanical features of these 1949 Dodge cars with only two words, those words would have to be "simplicity" and "durability". The tradition of rugged dependability was carried on. Little had changed from the 1948 models; refinement was again the outstanding characteristic.
The compression ratio was 7.0 [raised from 6.7] with a token one horsepower
increase to 103 HP at 3600 RPM. In line with the trend toward naming mechanical
features, it was christened the "get-away" engine. Perhaps that
overstated the case a little, for neck-snapping performance was not among 
its credits. In fact, a 0-60 time of 19.03 seconds was the best Motor Trend
could get in testing a 1952 model [identical power train to the 1949's]. It
found the top speed to be just below 85 MPH. However, that was a brand new car,
and many Dodge owners could attest to several more miles per hour once the
engine was fully broken in. That break-in time incidentally, was reduced by the
use of chemically treated cylinder walls.
It was a very strong engine noted for its extreme reliability, and it compared favorably with competition. For example, the 1949 Pontiac six offered only 90 horsepower from 239.2 cubic inches and a 6.5 compression ratio while its straight eight put out 104 HP from 248.9 cubic inches and 65. compression - only one more horsepower than the Dodge six. Dodge also used light aluminum pistons versus Pontaic's heavier nickel alloy pistons. Other features such as 'floating-power" type engine mountings, oil filter, full pressure lubrication, and automatic choke could not always be found on other engines. And for the first time on any make, the engine was started by just turning the key, thus eliminating the starter button.
Pontiac had offered GM's Hydromatic as an option on its 1948 models, so there was some pressure on Dodge to offer something more in the transmission also.
Gyro-matic was a real bargain at $94.60 compared to $185.00 for and $212.00 for Buick's Dynaflow. Even overdrive on Mercury was more expensive at $100.00.
On the other hand, Gyro-matic was never a fully automatic transmission, as it still required a clutch for shifting into and out of reverse and between low and normal ranges. Each range contained two gears and shifting was accomplished by fully releasing pressure on the accelerator. A slightly audible click accompanied the shift. The low range was designed to be called on only when extra pulling power was needed at low speeds; therefore, the normal range was used for most driving. In fact, Dodge engineers estimated that about 95% of all driving could be done without the clutch, which did not have to be depressed at a stop since fluid drive was a necessary adjunct of the transmission. In the normal range the car would start out in third gear and shift into forth at the will of the driver at any speed above 11-14 MPH. Downshifting occurred automatically when the car speed fell much below that speed range or when the accelerator was floored at any speed below 35.
Owners of cars with this transmission could attest to its performance drawbacks. It is somewhat sluggish,especially when cold, and absolutely will not be hurried when it comes to shifting. Like the L-head six, it simply was not designed for the racetrack. Its virtues were, by intent of the designers reliaility, simplicity and economy and in those areas it excelled. Certainly Chrysler could have built a fully automatic unit, but such things were too complicated for Keller's tastes and he would not allow it.
For those who chose not to order Gyro-matic or purchased a model on which it was not available, the alternative was a manual 3-speed transmission with fluid drive.
This page has been copied from here.