Engine Of The Week: 1968 426 HEMI Engine

Engine Of The Week: 1968 426 HEMI Engine

The engine was a 1968 426 HEMI a customer wanted rebuilt to be put in a 1969 Roadrunner.

“Everything was just a disaster,” says Ray Banyas about a particular engine he recently rebuilt. “The whole thing was a big, rusted-up, corroded mess. The manifold was gunked up. The valve covers were all rusty. When it came in we had to take apart 30 years of wear and buildup.”

The engine Banyas so eloquently described was a 1968 426 HEMI a customer wanted rebuilt to be put in a 1969 Roadrunner.

engine1500
“The customer is a dentist, and she and her husband also own a Dodge Viper,” says Banyas, who is the owner of Victory Racing Engines in Cleveland. “She is the one with the lead foot, and she wants to race the Roadrunner against the Viper to see which is faster, the old school or new school.”

In order for the old school to have any chance, Banyas had to do a number on the 426 HEMI, but only after he cleaned all the crud and rust off.

engine2500
“We do everything when we rebuild an engine here,” he says. “Basically we line hone the engine, we bore it, deck it and make sure the gasket surfaces are flat. We also check the main bearing clearance and rod bearing clearance. We also pin fit the pistons and pin fit the rods. We balance the engine as well. We had to do a valve job on the cylinder heads and change the springs and retainers for the hydraulic roller cam. We checked the push rod length so that those would work with the hydraulic lifters. We checked the valve clearance and the compression ratio. I had to cc a head and cc’d the dome of the pistons. We had to do some machining on the heads to get the longer push rods to clear. The list goes on.”

engine3500
Banyas kept the engine at a 10-to-1 compression ratio for pump gas. He was able to use the original block and put a stroker crank in it. When the block came in it was already 60 over, so Banyas made it into a 4.320″ bore (70 over).

“We had pistons made for it, and put a hydraulic roller in it,” he says. “We ran the engine on the dyno and it made 636 hp at 6,000 rpm. It has a standard valve train on it as far as the rocker shafts and assemblies go. It has about 600 lift in it. It’s got a crossram manifold with dual quads, and we have the original carburetors for it, which were done by Chris’s Carb Shop.”

engine4500
Despite the rough condition the engine arrived in at Victory Racing Engines, Banyas was able to clean everything up and even painted the covers. The 426 HEMI is now running with K1 rods, a K1 crank, Hastings rings, COMP Cams valve springs and camshaft, Clevite bearings, Cloyes timing chain sets, and push rods from Smith Brothers. It’s a completely rebuilt engine.

“Back in 1968, my research showed that these engines put out about 425 hp,” Banyas says. “Usually one hp per inch was good back then. We had it doing 636 hp.”

engine5500
If you ask us, this customer is going to have an exhilarating race on her hands!

Article courtesy Engine Builder.

You May Also Like

Updating Your TPMS Tools Regularly Matters

You can ensure your read is accurate by updating your tool regularly.

Courtesy of Tire Review by Yanick Leduc

Picture this: Mark, an experienced tire service technician, is on the phone with a technical support representative from his TPMS supplier, inquiring why his new sensors don’t seem to work properly with the 2019 Silverado he’s servicing.

Mark: “The truck doesn’t seem to pick up the signal from the new sensor!”

Cabin Air Filters

Cabin air filters will protect the health and well-being of the driver and passengers.

Diagnostic Procedures For Stop/Start Systems

Stop/start technology is more than just a switch wired to the brake pedal and starter.

Brake Pad Wear Sensors

Brake pad wear sensors have been around for years and continue to evolve.

Topology and Your Scan Tool

Topology influences how you access the modules with your scan tool.

Other Posts

Ride Control Diagnostics From Tire Wear Clues

Learning how to read the tire and communicate your findings is the key to ride control service.

Understanding Engine Timing- Chains, Gears and Belts

Engine timing is critical for overall performance.

Air Filters and Fuel Trims

Modern engines rely on precise airflow and oxygen sensor data for optimal performance.

Mercedes Ignition Coil Pack Diagnostics

Replacing a single coil might not be the best approach to curing an engine of a chronic misfire.