Author Topic: Pontiac 350 Block ONLY Thread  (Read 17448 times)


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Re: Pontiac 350 Block ONLY Thread
« Reply #160 on: January 25, 2020, 07:19:34 AM »
"...How can you tell if it was a 4-barrel or 2-barrel?..."

Get the date code, from back by the dist hole, and the 2-digit block code from the front of the block, right below the front of the passenger side head. The date code is cast with the block. The block code in stamped into the block. The last digit of the 4 digit date code is the last digit of the year in which the block was cast. For example: if the last digit is a 5, the block was cast in 1975. The 1st digit is for the month. A=Jan, B=Feb, C-Mar, etc. Next 2 digits are for the day of the month. For example: 03=3rd, 10=10th, 24=24th, etc. 

Using the date code, figure what year model car that block most likely came in. For example: If it was cast after say July, it was most likely used in the following year model car, since those cars would hit the showrooms in the fall of the year,  before their year model designation. For example: Some '76 model cars probably made it to most dealers by say October, of 1975.

So, if you know the block was used in a '76 model car, you can use this site to plug in the year & block code, and it will tell you whether it came with a 2 or 4-barrel carb.


Just plugging in 1976 350 2-barrel engines, it gives you 15 different possible block codes. 6 of those engines used 488986 casting number blocks. The rest used 500810 casting number blocks. The 500810 blocks were also used in '77. I have one of those.

"...If you were comparing a 400 Pontiac to a 350 chev would it be worth it in that instance?..."

The answer to that would be strictly up to the individual paying for it. Would also depend on the exact specs of both builds.

"...Would a 350 Pontiac compete or supercede a Chev 350?..."

A 350 Chevy can be built to make lots of power. Same for a 400 Pontiac. But, in low compression factory stock form, neither engine makes much power.

For whatever it's worth, the factory rating for the 4-barrel 350 sbc used in a 1978 Bird was 160 net hp.


For a 1978 Bird, the low CR 400 was rated at 180 net hp. And, because of it's more cubes & longer stroke, it would have had more low rpm torque than the 350 Chevy.


« Last Edit: January 25, 2020, 07:33:43 AM by oldskool »

Re: Pontiac 350 Block ONLY Thread
« Reply #160 on: January 25, 2020, 07:19:34 AM »
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