Pair Of Pontiacs Getting After It
This Photo is from the Early 1960's when NHRA still had its "Nitro Ban " in effect and the sport saw a proliferation of twin engine "gas " dragsters.
M/T with Jack Chrisman Driving vs. Eddie Hill.
It looks like the US nationals at Indy.
The M/T car was using a pair of the lightweight BOP aluminum 215 engines.
Not sure what they actually displaced.
The logic was the weight penalty would be negligible. 430" plus if the engines could be bored/stroked.
Eddie Hill was using two full size Pontiac iron block engines. Hill's car if running 389'swould be displacing in excess of 778 ci . Lots of torque & hp but probably tough to get the clutches of the day to last very long. Dig the shape of gusset panels on Hill's frame.
Shaped like Pontiac arrow heads. Not sure if that was intentional but it turned out looking cool.
Stroker cranks were available at the time to take a Pontiac out to 480"
Hill ran dual slicks for awhile on the car at some point. The side by side engines were probably mated at the ring gears on the flywheels with engines spinning in opposite directions. Lots of extra engineering to run the twins in either inline or side by side configuration.
Using two to get the same power as you could make with one nitro motor at that time. All kinds of schemes were tried but eventually Nitro won out because all the non NHRA affiliated tracks were running nitro shows and packing in the crowds.The A.H.R.A. embraced the nitro racers. Finally NHRA caved in because they were losing ground and revenue to the A.H.R.A. .
The twins mostly disappeared by the early 1970's except for a few diehards that even tried running twins on fuel.Twice the weight and double the parts to look after.
The later 500" maximum displacement class rules was the real nail in the coffin for the big displacement twins.
Liquid horse power won out.
Step Away From The KOOL AID !
Last edited by sprint250 : 03-10-18 at 12:51AM.