Mopar #'s Matching
Commando 273 engines were 4 barrel engines and had a number of special HP parts. I'd first find out what you have. Casting numbers from the heads and block. Is your 273 solid lifter? Do you have exhaust manifolds and motor mount brackets? A friend of mine has a 67 4 speed Formula S Fastback and had his 273 dyno'd. With all the Commando good stuff and 2 barrel pistons, a small Isky E-4 cam, and a 600 Edelbrock carb the little 273 made 260+ hp at 5,500. In general If you are building any wedge engine, you should be able to get 1 hp per cubic inch and torque as well. A good 273 will move a 65 Cuda very well and get 20+ mpg. You are also limited by wheel well width. A High Performance 273 likes rpm and will easily run to 6,000 to 7,000 rpm with stock heads. I had a 64, 4 speed Cuda as a daily driver for decades. Loved that car. Any small block will really move that car. Here are some stock hp numbers from one of the Chrysler Racing manual. Notice that a 318 2 barrel does not make any where near 230 hp. Depending on what you have, all engines are similar in cost to build. What do you have available? What do you really want the car to do? Start there.
Commando 273 engines were 4 barrel engines and had a number of special HP parts. I'd first find out what you have. Casting numbers from the heads and block. Is your 273 solid lifter? Do you have exhaust manifolds and motor mount brackets? A friend of mine has a 67 4 speed Formula S Fastback and had his 273 dyno'd. With all the Commando good stuff and 2 barrel pistons, a small Isky E-4 cam, and a 600 Edelbrock carb the little 273 made 260+ hp at 5,500. In general If you are building any wedge engine, you should be able to get 1 hp per cubic inch and torque as well. A good 273 will move a 65 Cuda very well and get 20+ mpg. You are also limited by wheel well width. A High Performance 273 likes rpm and will easily run to 6,000 to 7,000 rpm with stock heads. I had a 64, 4 speed Cuda as a daily driver for decades. Loved that car. Any small block will really move that car. Here are some stock hp numbers from one of the Chrysler Racing manual. Notice that a 318 2 barrel does not make any where near 230 hp. Depending on what you have, all engines are similar in cost to build. What do you have available? What do you really want the car to do? Start there.
