I thank you for the feedback. I don't know the "specifics" much on all this stuff, I just find it and then do some quick research & realize it's Discontinued rare stuff and I'm like *I need it* lol... I just like to collect the Vtg performance stuff, air cleaners, valve covers you know. but I also love to restore stock stuff & resell it also.If this is your current intake I will bet that it perform better than the Holley you posted
It is a true dual plane since the divider is not cut down like the Holley and it is a square bore carb bolt pattern like your 390 instead of a spreadbore design with dual bolt pattern.
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