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Old 12-20-2016, 10:04 PM   #7
38Chevy454
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Join Date: Mar 2015
Location: Cincinnati
Posts: 146
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So I read up and learned there are some unique features of the 8.1. It is based on the old big block, but with a lot of differences. The block is a tall deck version, has the same std Chevy bellhousing pattern, but a unique flexplate. The cylinder heads have cathedral ports, kind of like the LS engines have. That is significantly different then the old 7.4 which had the small "peanut port" heads which were smaller than the regular oval port bog block heads. The 8.1 also does not use the std distributor, like most newer engines it has the distributorless ignition.

Most of the general comments I found said they make good power and torque, and especially like to burn gas while doing it.

So as stated by hot rod above, scratch my idea to use the 7.4 intake and TBI as an easy swap. It won't work. I was not aware of the tall deck and the unique cathedral intake ports. Now I know why nobody really uses the 8.1 for high perf builds. I'll stick with the old style big blocks that I am familiar with! Sorry for the confusion.
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