[bigblockv6]

The 1960 351C put out 155hp while the 1966-70 351M & E engines put out 190hp, these are net figures so there's a 35hp difference. You can closely get get the power up to the Magnum level just by replacing the small ww carb with the Holley 500 carb. Realisically if you want a real power increase a 401M engine will be a better choice. 351C engines were one of the longest produced GMC V6's from 1960-72 as far as that designation and applications are concerned. Why nobody talks about them is due to interest in Magnum head engines. The 351C is still a decent upgrade over a 305 V6 and good chance more plentifull over all the other larger displacement V6 engines.