Back to ‘stock’ 340s, I’m putting together a 70 Duster for stock with the 340. I’ve talked to a few running these cars, picking their brain thing. One gent who has raced his 71 since new turns his 7500 when heads up 6500 in bracket mode. Mid to low 10 sec ETs, he said it’s all about the valve springs since all componites have to be same weight and NHRA approved replacement. Makes you do a double take when hood is up and there’s a stock looking engine with cast iron heads and intake with an AVS, running that fast.