6.2 and 6.5 head interchangeable?

[kevmcgill]

Hello all- I realize the the head gaskets are interchangeable on the two engines but, are the cylinder heads also? I have a 91 K3500 6.2 with a cracked head and a guy on Craigslist (with heads off a 93 6.5) says they are interchangeable. The parts dept at the local chevy dealer says nope. Any experience/advice/thought is greatly appriceated. BTW my engine code is J.
Kevin

[john8662]

They will interchange. The later 6.2's pretty much have later designed heads anyways (injector angle change).

The main difference is that the '93 6.5 heads will have large precups, which could hurt fuel economy slightly.

If you decided to go this route, you would need to do both heads.

Verify the cast number on your old head verses the new head, you'll likely find that they are the same, except one has the turbo precups in it.

Swap Precups? Maybe, and I do mean maybe, depending on machine work performed on any of the heads, the cups might not seat properly. I can go more into this later...

J

[kevmcgill]

They will interchange. The later 6.2's pretty much have later designed heads anyways (injector angle change).

The main difference is that the '93 6.5 heads will have large precups, which could hurt fuel economy slightly.

If you decided to go this route, you would need to do both heads.

Verify the cast number on your old head verses the new head, you'll likely find that they are the same, except one has the turbo precups in it.

Swap Precups? Maybe, and I do mean maybe, depending on machine work performed on any of the heads, the cups might not seat properly. I can go more into this later...

J

Picked up the heads today and I'm half way into the pulling of the old ones. Those exhaust bolts are a you-know-what to get off! Is there a baseline I should consider now that I'm "in there". I was planning on rebuilding or cleaning the injectors. What else should I consider? Keep in mind I work in the trades and times are tough money wise.
Thanks a bunch for the feedback.
Kevin

[john8662]

Just your parts list...

I'd suggest getting a tap to clean all the threads in the block for the new head bolts. Besides that all new gaskets, etc.

J