I am aware of an Edelbrock Performer intake manifold for the 351M & 400. I'm not enthusiastic about using a Performer intake in a Pantera, its OK in a truck, RV or tow rig, but not a sports car.
A good combo would be the iron 4V closed chamber heads (out of your current motor?), the Blue Thunder intake with adapter plates & the Comp Cam XE284H flat tappet hydraulic cam.
Better yet, contact Mark McKeown of MME Racing, he'll have some good ideas to make a great Pantera motor out of the 400, and can grind you a custom cam that fits your needs ideally.
I hang out on another forum for the 351C engine, and you read nothing but praise for Mark's work.
George
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