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The 454 TBI flows about 640 CFM it is just a little smaller than the 670 CFM Holley. However fuel is computer managed. As a result what can be done to hop up this engine is very limited before you're into reprogramming the computer.

Transmission if an automatic will be the 4L80E it needs a computer to operate so changes to the engine say like TBI to carb and ignition to HEI require the computer be fed tach, throttle position and Manifold Absolute Pressure (MAP) data is it does now in order to modulate shift pressure.

So changes are possible but must be planned out.

Cam can be increased to an intake timing closely around 200 degrees at .050 lift and the LSA is kept not less than 110 degrees, here bigger is better. TheTBI computer will most often adjust to this if your factory O2 sensor is working.

Big tube long primary headers are very effective as is a 3 inch dual exhaust system.

Compression ratio on this engine is miserably low but nothing much can be done without deep surgery. Here the bore diameter of these engines really works against you where detonation is concerned. Aside from aluminum heads compression creases must be carefully orchestrated with regard to piston selection and deck clearances.

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