« Reply #7 on: August 27, 2019, 07:59:43 PM »
I’m in the leave it alone crowd.
I would bet that manifold (untouched) will drastically outflow your heads. If this is the case, opening your manifold ports will only slow the air/fuel charge velocity.
I know this isn’t exactly apples to apples but my 557 BBF has the same mismatch with Kaase P51 heads and an Edelbrock intake manifold. Jon Kaase’s guy told me to leave the manifold alone. That motor makes 900hp and 801 torque with untouched manifold and heads.
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ERA 427SC Cobra: Iron ‘67 625hp 482” SOHC, TKX 5 speed, TrueTrac 3.31 IRS, Magnesium Halibrands, Avon CR6ZZ tires.
1969 Shelby GT350, 4 speed.
1967 Mustang Fastback: Close ratio T56 Magnum, Fab-9, Wilwood superlite brakes, Torque arm rear suspension, TCI-IFS with shock tower delete, (Coming soon, FE motor TBD)
1970 F250 4x4 Mud Truck, 557 BBF, as cast P51 heads, 900 hp @6700rpm, 801 tq, Q16, C6.
2012 Cobra Jet Mustang factory drag car, 5.4 liter 4.0 Whipple, 970 RWHP.
1964 Galaxie 500XL, 35 spline 3.70 Strange S-Trac, 6R80, (Coming soon: Pond Aluminum 525 SOHC, 800hp)