I would go with the C4. They are very lightweight and are strong enough for applications up to about 400 hp. Very good for quick accelerations around town...
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'69 Coupe with 351W
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Edelbrock Performer-RPM highrise dual plane intake manifold, Edelbrock Performer-RPM hydraulic cam (224 int duration, 234 exh; .496 int lift, .520 exh, and it idles just fine), Edelbrock Performer 750 cfm 4-barrel carb, Accel coil, Moroso Blue-Max plug wires, Hedman headers, 2.5" pipe, dual Thrush glasspacks, Edelbrock Performer-Link timing chain, C4 with B&M Street/Strip Shift Kit, Lakewood traction bars, 3.55's, 3200 lbs...
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