1972 K-5 Blazer 350

[Ian Villeza]

I just bought a 72 blazer with a 350, I found a site listing the horsepower at 175. Does this seem low for a 350?

 

[Blazer1970]

175 HP is correct. GM went to net HP ratings for '72 instead of gross HP which had been used earlier. The same engine was rated at 255 gross hp in 1971. The first truck 350 that made over 200 net hp was the TBI motor in 1987.

 

[Ian Villeza]

Does that mean my engine is rated around 255 Horsepower in todays rating?

 

[PsychoticDeadGuy]

hold up...so what is the gross hp rating for the '87 350?

 

[Hannibal]

Check the casting numbers, if it's a "0010" block it might still be a 2 bolt main not guarrenteed 4 bolt but they are a high nickle block and can take a .060 overbore. The early camshafts are usally kinda week, but overall a very nice block to build on.

 

[Blazer1970]

Does that mean my engine is rated around 255 Horsepower in todays rating?

No, the ratings that manufacturers still use are net hp. These engines were not that powerful in comparison to a new fuel injected motor. A lot of the ratings that people throw around in the aftermarket are a lot closer to the old gross hp ratings than net hp though.

 

[Blazer1970]

hold up...so what is the gross hp rating for the '87 350?

No idea. They don't rate them that way any more.