I had a set of ported 6X-4 heads done by SD Performance over 20 years ago. I asked Dave when he surfaced them to only remove the minimum amount required for surface cleanup.
The chambers ended up at 94ccs.
So another data point.
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1964 Tempest Coupe LS3/4L70E/3.42
1964 Le Mans Convertible 421 HO/TH350/2.56
2002 WS6 Convertible LS1/4L60E/3.23
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