I owned a 1971 Duster 340 ! it had a 3 speed Manual Transmission.
By adding a Moroso Valley Baffle, under an Edelbrock TM5 " Tarantula " Manifold
with a Holey 700 cfm " Double Pumper " Carburetor,
When you " Floored It ", the " Blue " Primary Pump Cam ( # 2 hole, 30 cc ) & the " Brown "
Secondary Pump Cam ( # 1 hole, 50 cc ). THE CAR WOULD ABSOLUTELY FLY !
Stock Exhaust Manifolds, connected to a pair of 2 1/2 Exhaust Tubing, X-Pipe & Corvair Turbo
Finally an Accel Dual Point Distributor, 12 deg in the Distributor Plus 10 Deg Lead @ Idle.
My best guess was it had a 3.23 " Open " Rear End. 275 HP, at the Rear Wheels, MAYBE !
ALL OF THIS MADE THE CAR SUPER STRONG & in a Race on Sunset with a Ford Boss 302,
I was leading them, until the light changed to Red. I STOPPED, they Didn’t, they passed me,
running the red. I LAUGHED MY HEAD OFF, when I pulled away from the light & saw a
Motorcycle Cop Ticketing the Mustang. I NEVER SAW EITHER OF THEM AGAIN !