f70s on a BB (even an LS6 [img]<<GRAEMLIN_URL>>/shocked.gif[/img] ) '70 Chevelle was laughable (way undersized series-wise and wheel size-wise) particularly when u consider what the competition at the time was shodding their cars with. Hemi cars got the G60-15s, even Olds had the G70s on their 455 cars. I suppose Chev. figured their customers would replace tires/wheels anyway for their Chevelle SSs so they saved money on tires to keep their prices more competitive.
The answer to your question depends. Are you going for correctness, better performance, personal likes, looks, driveability, etc. If you are not going for correctness....do what floats-your-boat!! There is nothing to say that an owner back in the day would not have upgraded his tire series to improve performance. It probably happened once or twice. [img]<<GRAEMLIN_URL>>/whistle.gif[/img]
P.S. I like Don's BLUE BEAST too!!! [img]<<GRAEMLIN_URL>>/
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