• Also known as the "W-series", Chevrolet's 348 and 409 V8 engines were legends in their own time. Although the 409's relatively brief production run from 1961 to 1965 should have relegated it to relative obscurity, this engine proved nothing if not a precursor to the most prolific horsepower wars in the history of internal combustion engines. While more modern aftermarket parts abound (particularly if you use one of the new aluminum aftermarket blocks that utilize a big-block Chevy camshaft), many owners prefer to restore their fine 409s to factory spec.
  
  

Cams 3796077 and 3796076

• This cam was used on 360 horsepower engines produced in 1961 and all 409s produced until the middle of April of 1962. This cam used 345 degrees of total duration on the intake side, which opened 59 degrees before top dead center and closed 106 degrees after bottom dead center. The exhaust side opened 97 degrees before bottom dead center and closed 26 degrees after top dead center for a total duration of 304 degrees. Intake and exhaust lift were both 0.4396-inch. Note: bear in mind that these total duration specs are absolute to the cam, which rotates twice per engine revolution. Divide total duration by two to get the cam-relative lift used today. For instance, this cam's duration would be 172/152 degrees on the intake/exhaust by today's measuring system.
  
  

Cam 3830690

• This cam was used on 380 and 409 horsepower engines produced in 1962. The intake opens and closes at 86 BTC and 132 ABC (respectively) for a total duration of 398 degrees, and a valve lift of 0.4396-inch. The exhaust valve opens 93 degrees BBC and closes 79 degrees ATC for a total duration of 353 degrees and a lift of 0.4396-inch.
  
  

Cam 3837735

• This cam was used on 400 and 425 horsepower engines produced in 1963. The intake opens at 110 degrees BTC and closes 154 degrees ABC for a total duration of 444 degrees and a total lift of 0.5069-inch. The exhaust opens 193 degrees BBC and closes 143 ATC for a total duration of 416 degrees and a total lift of 0.5185-inch.
  
  

Cams 3822930 and 3837446

• The former cam number was used in 435 horsepower engines produced in 1963, 400 and 425 horsepower engines produced in 1964 and 1965. Their intakes open 49 degrees BTC and close 93 degrees ABC for a total duration of 322 degrees at 0.5069 lift. The exhaust opens at 95 degrees BBC and closes at 45 degrees ATC for a total duration of 320 degrees and a 0.5185 valve lift.
  
  

Cam 3838416

• This cam was used in base-model 340 horsepower engines produced from 1963 to 1965. Its intake opens at 38 degrees BTC and closes at 93 degrees ABC for a total duration of 312 degrees and a valve lift of 0.4005-inch. The exhaust valve opens 88 degrees BBC and closes 51 ATC for a total duration of 320 degrees and a valve lift of 0.4119-inch.