1968 '340' Barracuda vs 1968 '383' Road Runner
Rico,
Here is what I found.
Colony Chrysler-Plymouth
Plymouth, Michigan
1968 Plymouth 383 Road Runner Test
November 1967
A 1968 Plymouth Road Runner 'Pillared Coupe' 383 4-Speed was tested at
Motor City Dragway @ New Baltimore, Michigan in November 1967.
According to the Dealer Report, the Road Runner came from the Factory with a 3.23 Gears w/Sure-Grip.
Which the Colony Plymouth Dealership replaced with a 3.91 Sure-Grip Gear set-up.
The Distributor received a 'Performance Curve' and the Carter AVS was 'tweaked' for optimal performance.
The 383 Road Runner ran a best of 14.44 @ 98.46 MPH, on stock F70 X 14" Tires.
According to the Dealer Test, the F70 X 14" Tires were replaced with a set of 'M & H' 8.50 x 14" Cheater Slicks.
The Road Runner was re-tested, and ran a best of 14.04 @ 100.26 MPH
* Shift Points were at 5200 RPM's
* Valve Float @ 5400 RPM's