I wouldn't pay more than 300.00 for any BBB engine core, and that is what they are unless you can hear them run. The best cores to build are the 75-6 engines. It really depends on how much power you are looking to make as well. Core shift can disqualify an engine block if it is severe enough. If you want to make north of 500 HP, you are looking at well ported iron heads, or aluminum heads. The LS engines will be the cheaper way to go, make no mistake about that. Some good information in these threads,
If you are questioning what year motor to start with for your big block Buick (BBB) build-up, this thread is for you. (If you are looking for a ’70 SF...
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Understanding Core Shift in the 455 block- why sonic checking is so important Compliments of Jim Weise @ www.v8buick.com 2-14-2009 Hi Folks Let's talk about the 455 factory block, and dis-spell some myths about the various 455
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