95 N N Code big block swap question

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fast 99

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Have a friend who wants to install a big block in a 78 K10. Wondering if a N code 1995 big block swap will work? Wants to use the older brackets, pulleys and manifolds from an 80's truck making it appear stock for the era. Am thinking it will work but need an aftermarket carb intake to fit the heads.
 

nvrenuf

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Have him do some research first. The 1995 block is a good motor but from a parts standpoint it’s odd. There are 3 designs of big blocks, “Mark IV” from beginning to 1990, “Gen V” from 1991-1995 and “Gen VI” from 1996+.

The Gen V motors had some undesirable design changes which makes them odd and limits interchangeability.

If he really wants / needs it to look like it came in the 78 truck, this isn’t the motor. There is no mechanical fuel pump boss on these so that will be a dead giveaway.
 

fast 99

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Have him do some research first. The 1995 block is a good motor but from a parts standpoint it’s odd. There are 3 designs of big blocks, “Mark IV” from beginning to 1990, “Gen V” from 1991-1995 and “Gen VI” from 1996+.

The Gen V motors had some undesirable design changes which makes them odd and limits interchangeability.

If he really wants / needs it to look like it came in the 78 truck, this isn’t the motor. There is no mechanical fuel pump boss on these so that will be a dead giveaway.
Kind of what I thought. Lack of fuel pump boss isn't a killer but will require changes to the truck. The core motor is cheap. That's why the question. It has a good running small block now think I will recommend it stays. Would be easier/cheaper to build a 383 or 372 SB. Thanks
 

nvrenuf

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Also know that the heads are the smaller peanut port type. Most folks prefer the earlier Mark IV oval port heads, they will fit the Gen V but it requires special gaskets. Just lots of little weird quirks.
 

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