http://www.autohobbydigest.com/ddart.htmlperfacar saidhi, the 275 hp/273 was sold for the street use. only difference was, larger cam, headers, racer brown springs, holley carb, 4.86 gears. rest of motor was same as 235 hp/273. C.P. pistons makes 235 /273 pistons. egge also.
isky makes a very good grind for the 273, E 4 grind, works very well in 273 motor. the 1966-67 heads are closed chamber style, used on 273 /318 in those years.1967 for 318 though.
The 1966 D/Dart
The 1966 D/Dart
The 1966 Dodge D/Dart was a Factory Dart package built solely for drag racing. The 273 v8 was rated at 275hp and weighing in at just over 2900 lbs. The car qualified for NHRA's D/Stock category.
Dodge's normally aspired high performance 273 was rated at 235hp. The extra 40hp the D/Dart produced was basic hotrodding. Off the speedshop shelf bolt on's included Racer Brown valve springs, a Camcraft 284-degree .500" lift cam, Doug's Headers, and a Holley 4160 bolted to the stock intake. All were equipped with the A-833 4 Speed and a Hurst shifter, Weber clutch components, and an 8 3/4 Suregrip with 4.86 gears. Unavailable for this car were air conditioning and a warranty. There were no external badging or markings to note the D/Dart package over a regular Dart GT.
The picture in the 1966 Car Craft article was of a white Dart GT with Cragar S/S mag wheels. They tested the car at 14.33 @ 92.21 mph.
This kind of package makes the identification of an original D/Dart nearly impossible without a paper trail, or some photographs. The cars were Dart GTs (I can't find any information to suggest that the D/Dart package was available in a sedan except for the fact that the lighter sedan might have put it in a different NHRA category). 1966 cars can be certified by obtaining a copy of the IBM "punch card" for the vehicle that indicates sales codes.
These cars should have a VIN that begins LO23 or LP23. The order should include the following sales codes: 699 - Special Order (Super Stock Dart); 409 - Special Order Axle; 364 - Super Stock; 624 - heavy-duty suspension; 32 - engine code; 554 - delete rear seat belts; 393 - four speed transmission; 21 - 6.95 X 14 BSW rayon 2-ply tires; 408 -Sure Grip; P4H - trim code (red); WW1 - paint code (white).