The current combination (setup of the engine, transmission, rear end, weight, etc.) of an Edelbrock Torker II manifold and a CSR tapered four-hole 1-inch carb spacer has resulted in consistent 60’ times in the 1.52-1.55 second range with mid-to-high 11.40s in the quarter mile in the 114-mph neighborhood. The current setup has produced an all-time best ET of an 11.358 at 117.17 mph with a 1.500 second 60’ time was clocked at Numidia Dragway (Numidia, PA).

The plan for the 2017 season is to run a full season of heads-up 11.50-second index class races at Atco, Englishtown, and Maple Grove drag strips, and during the warmer months, the ETs tend to drop off positioning the current setup dangerously close to not being able to cover the 11.50 index. The concern of not covering the index is the reason for the change from the single-plane Torker II to the divided runner dual-plane Performer RPM Air-Gap manifold. The belief is that the RPM manifold will provide additional low- and mid-range torque helping to propel the Dart down the track a few hundreds to a tenth of a second quicker in the quarter mile thus adding some cushion to compensate for the dog days of summer.

The testing of the manifolds and spacers would occur over back-to-back weekends at Beaver Springs Dragway (Beaver Springs, PA). The first weekend would establish the baseline of the 340’s current setup of the Torker II manifold, the CSR tapered 4-hole spacer, and the optimized Holley carburetor. The next weekend would be the testing of the RPM Air-Gap manifold along with the three carb spacers, and jetting adjustments of the Holley carburetor.

Engine and Car

The 340 is fed via an annular discharge 830 cfm Holley four barrel. The carburetor has been optimized for the current combination with 84 jets in the primaries and 86 jets in the secondaries. The 50-cc accelerator pump pushes fuel to the .035” primary discharge nozzle squirter. The secondary discharge nozzle is also a .035” squirter. The 340 with the Torker II manifold and the tapered 4-hole spacer proved a solid baseline elapsed time (ET) of 11.374 at 114.94 mph. The 340 pulled the Dart to a 1.503 second 60’ time.

The 340 is a .040” over ’68 block with a ’68 stock forged steel crankshaft that swings Scat H-beam rods connected to factory replacement forged Speed Pro pistons and pins. The camshaft is a 26-year-old solid-lifter Direct Connection Purple Shaft with a .557” lift and an advertised 296 degrees of duration. A pair of gasket-matched Edelbrock aluminum cylinder heads top the block and Dick Landy prepped 1.5:1 roller rockers actuate the valves while oscillating on their respective hardened rocker shafts. For the baseline testing, the beforehand mentioned gasket-matched Edelbrock Torker II manifold rests on the heads and a 1-inch CSR tapered 4-hole spacer coupled with an annular discharge Holley 830 carburetor sits atop the engine.

Edelbrock’s Torker II (part no. EDL-5076) features a low-rise, single-plane casting that is designed to maximize the top-end horsepower without disturbing the mid-range power. The intake is designed to minimize the turns of the intake runners, thus allowing the air-fuel charge a nearly straight shot from the carburetor to the intake valves. This manifold is designed to make power from 2,500 to 6,500 rpm.