Match Race 1972 ~ 'Duster 340 vs 'GTO 400'

O-M-R

1972 Pontiac 400/250 HP ~ #7K3 ~ Cylinder Heads
Intake Flow @ .450" Lift......... 201 CFM
Exhaust Flow @ .450" Lift....... 155 CFM

1972 Pontiac GTO 455/250 HP ~ #7M5 ~ Cylinder Heads
Intake Flow @ .450" Lift........ 165 CFM
Exhaust Flow @ .450" Lift...... 108 CFM

Same Valve Size 2.11" Intake and 1.77" Exhaust

The 'Pontiac Book' states that in 1972, the 400/250 HP with a TH-400 Automatic was non-performing
in the Torque Department, so Pontiac put in a few 455/250 HP {Code L-75} engines in a limited amount
of {Automatic 'only'} GTO's, which provided for massive amounts of low-end Torque.

455/250 HP {L-75}........ 475 Ft/Lbs. @ 3400 RPM's
versus
400/250 HP {L-78}....... 325 Ft/Lbs. @ 3200 RPM's

* Standard Gears.... 3.07 {Squealing Tire Smokers}
* Optional Gears..... 3.31