305 to 350 swap

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BUCKLEYT

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Hello, new to the forum and gmt400 platform. just recently swapped a 350 into my 98 that originally had a 5.0, but spun a main bearing. Will my pcm from the 305 be just fine running the 5.7, or should i swap pcms as well? The doner vehicle is a 99 suburban, and I was told that it would run just fine but wanted to confirm from someone who has done it before. Thank you!
 

b454rat

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IMO, not enough of a difference. I had a 96 that had a 305 in originally, after pulling motor found out it was a 350. No clue if ECM was changed or not.
 
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