273????

The 66 273 uses the same bolt angle as the later models on the intake. The Commando/Charger 273 had domed pistons to get the 10.5:1 compression ratio. These are not available in repo as far as I know. The cam specs are .425 lift, 248 degrees duration and 46 degrees overlap.

The carburetor was an AFB 3855S rated at 625 cfm. Intake manifold was a single plane cast iron unit.

All of the early 273s used mechanical lifters. The engine produced 235 hp @ 5200 rpm and 280 ft/lbs of torque at 4000 rpm.

Another consideration for cylinder heads with the flat top pistons would be casting # 4323302. This has small valves and heart shaped combustion chamber (62.6 cc chamber volume). The head would also have hardened valve seats for use with unleaded fuel.


RE: D/Dart (Factory Notice)

Dodge Offers "D" Stock Dart

DETROIT -- A new 275-h.p. Dodge Dart GT that meets D Stock specifications of the NHRA, AHRA and NASCAR is now in production. The "D/Dart" has a shipping weight of 2,946 pounds.

The "D/Dart" features a modified 273-cubic inch engine with a special four-barrel Holley carburetor. Other features include: A special Camcraft camshaft (284 degrees with .495 intake and .505 exhaust), Racer Brown valve springs, a modified, full-breathing intake manifold, a
low-restriction air cleaner, and a Weber clutch.

Other standard items are: a heavy-duty 4.86:1 Sure-Grip 8-3/4 inch rear axle, free-flow exhaust headers by Doug of California, a four-speed manual transmission, heavy-duty suspension, and 6.95x14 B.S.W. tires.

The "D/Darts" are regular production line automobiles.

Additionally certain, basic service parts will be available through the Chrysler Parts Division, so that owners of earlier Darts may convert from the 235-h.p. to the new 275-h.p. version of the 273 V-8 engine.

The "D/Dart" has been certified by the sanctioning agencies in the D Stock class. It is expected that this car, properly prepared, will be a top contender.

A high idle speed minimizes roughness, a high numerical axle ratio is used for top acceleration, the distributor is modified for quick advance, and the ignition system is designed for optimum engine output. Due to the expected use of these vehicles, no warranty coverage applies.

Those who are interested in more specific technical details on this car may contact staff engineer Dick Maxwell, Product Planning, Chrysler Corporation, 341 Massachusetts Ave., Detroit 31, Michigan. Phone 313-883-4500, ext. 3947.

In case your local Dodge dealer does not have a full list of the part numbers for these specific components you may wish to contact performance parts specialist Ray Ryder, Chrysler Parts Division, 22631 Lawrence Avenue, Centerline, Michigan. Phone 313-539-3000, ext. 7763