What is your compression ratio? If your tune is good, the right converter and cam will do wonders with 3.54's.
What do you have the timing set at, initial and total? What do your plugs look like? You can easily change the cam and lifters with the motor in the car without removing the intake. You can always contact Dave over at Hughes Engines and talk to him about your set-up and see what he recommends.
1970 Plymouth 'Cuda #'s 440-6(block in storage)currently 493" 6 pack, Shaker, 5 speed Passon, 4.10's
1968 Plymouth Barracuda Convertible 408 Magnum EFI with 4 speed automatic overdrive, 3800 stall lock-up converter and 4.30's (closest thing to an automatic 5 speed going)
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