“What’s really unique about this engine, is that it’s probably the first Gen II Hemi we’ve ever seen that’s running a drive-by-wire throttle body setup,” boasts Eric Hruza, president and CEO of Arrington Performance. “We’re using the Holley Dominator engine management system that was originally built for the Gen III Hemi, but with some very minor modifications it works on the Gen II – and we made well over 1,100 horsepower with it running low ProCharger boost from an F-2 supercharger. It was a win for sure.”

The 528ci elephant was built for a custom car that will be showcased at SEMA. Using the drive-by-wire system was a unique challenge for the Arrington team, but Hruza recounts that it was very much plug-and-play with the Holley setup. The two companies have been collaborating on projects like this for about a year-and-a-half, and Hruza and his team are very satisfied with the level of powertrain control the Dominator offers. In fact, a company objective is the flexibility to use Holley’s EFI systems with all of the stock Chrysler technology; thanks to the built-in options in the Holley system they’re well on the way to achieving that. It’s not a plug-and-play with stock vehicles, though. The next step in the process is controlling the Mopar electronic transmissions, and Hruza says that’s on the horizon as well.

Plenty of dyno time

The amount of time spent on the dyno learning various Hemi combinations, what the engines like and dislike, and how they respond to various changes is a hallmark of Arrington’s development process. Although the owner of this engine can’t be disclosed at this time, Hruza says it’ll be a jaw-dropper once it debuts at SEMA and that Arrington is proud to be associated with the project. They are also very appreciative of the patience shown to them by the customer as they went through the build process.

Molnar Technologies supplied the forged steel 4.150-inch stroke crankshaft and the forged connecting rods for this project.

It’s not just any standard 528 cubic-inch Hemi engine – it’s based around an Indy Cylinder Head block that uses a 4.150-inch stroke crankshaft and forged connecting rods from Molnar Technologies, a set of Diamond pistons, Comp Cams valvetrain, along with a set of Gen II Hemi heads from Edelbrock to process the ProCharger F-2’s boost.

Getting drive-by-wire to work

“The bottom end build was pretty standard, but once we got up to the intake manifold, we had to add a place to install the injectors, do some fabrication to make the throttle body work, and once we got to that point it was up to the calibrator to get the drive-by-wire throttle body to work,” says Arrington’s Chris Martin.

Edelbrock’s Gen II cylinder heads were used along with the custom-fabbed Edelbrock/Arrington dual-plane intake manifold. The F-2 ProCharger provides the extra motivation.

Setting the engine clearances were specific to this boosted engine, and with that in mind the piston material was selected from 2618 forged aluminum; the rings are tool steel to hold up to the extra pressure the engine sees.

The intake manifold is a dual-plane carburetor design that has a custom bonnet welded on top to mount the throttle body. The use of the dual-plane design is different, specially for a seriously-boosted engine such as this.

Martin says that the manifold was already under construction so the team decided to try it out and see what kind of results it would offer in practice – and it worked out quite well as proven by the results on the dyno. Since all that’s moving through the intake manifold is air, he doesn’t feel that it is hurting as much as it might on a carburetor-equipped engine.

Finishing touches

“There was some fine-tuning required, but the tune was very close right from the start. There are other things we could have done for different items like the camshaft to tailor the engine for different applications – this engine has a solid roller camshaft in it – but you could do a hydraulic roller camshaft in this engine with no problem,” says Martin.

“All of the beautiful fabrication and design work to make everything fit together was performed here at Arrington by Joe Helms. The very cool ProCharger custom dome that’s on top of the engine was hand-fabricated and welded by Joe. He also had to notch out the valve cover to make everything fit. As this engine is going into an E-body car, we had to keep the supercharger as close to the engine as possible so as to not have any interference with the body. We used a drive system from The Supercharger Store that we further modified to work for our needs in this particular application. A lot of work and a lot of time to make it happen. It’s all just a work of art,” says Hruza.

Arrington does it again – check out the sights and sounds of a boosted Gen II monster!