Measuring in at over seven feet wide, the Hummer H1 is an extremely looming figure to see in your rearview mirror on your morning commute. Originally designed for the armed services as the HMMWV, the civilian version carries over a vast amount of the design perks that make this a seemingly unstoppable vehicle. Although the size may seem overwhelming, Bob Edmunds of Hot Springs, Arkansas, has no problem wheeling this behemoth around for his daily tasks.

“The tuning was dialed in perfectly to maximize spool up and minimize smoke.”

Creature Comforts

In stock form, the H1 Alpha comes equipped with a 6.6L Duramax backed by the venerable Allison 1000 transmission. The H1 is built for business, with even the civilian models lacking in the creature comforts area. Edmunds addressed this issue head on, dropping it off with Adam Chumley to have the interior gone through. The seats were all reupholstered in gorgeous black and peanut butter leather, really bringing a level of class to the interior. To drown out any road noise and keep the passengers entertained, an Alpine entertainment center was installed with extra screens so the passengers can watch movies on the way to their destination. The sound system was wrapped up by Jason Vickers of Electronic Service in Texarkana with a full set of JL Audio six and a half inch speakers being fed by a pair of JL amplifiers to make sure the tunes are loud and clear.

The Duramax is shoehorned into the engine bay, leaving very little room for flashy accessories. What you can’t see is the Danville 3794 and the Exergy 30-percent over injectors.


As much as an H1 Alpha stands out in factory form, that wasn’t going to be adequate for Edmonds. More attitude was gained with a call to Predator Inc. for a replacement hood, grille insert, front and rear bumper, headlights, as well as the roof rack. Once all of the upgrades arrived, they were painted the same deep, wet black as the rest of the truck. To wrap up the visual upgrades, as well as upgrade the off-roading capabilities, a set of twenty-two inch S.O.T.A. wheels were wrapped in thirty-seven inch Toyo mud terrain tires.

Duramax Power

All of this makes for a truck more than worthy of the most rugged assaults on the daily commute, but with all of the added weight, more power was an inevitable addition. The crew at Pressurized Performance were given the nod for the task of juicing up the Duramax under the hood. The first addition was EFI Live programming from LJC Performance, but more was desired. Danville Performance supplied a new lung for the heavy H1 in the form of one of their modified Garret 3794 turbochargers. The turbo was upgraded with a billet batmowheel before it was sent out for installation. This turbo setup provides plenty of cool air, as well as putting out a shrill whistle not to be mistaken for stock. With extra air on tap, a set of Exergy 30-percent over injectors were added to fuel the fire! With the new modifications made, Lee Algood at LJC was given the truck to get the tuning dialed in perfectly to maximize spoolup and minimize smoke. When looking for a lift pump to supply low pressure fuel, the crew had to do some fabrication for the FASS pump mounting; after all, very few things are designed for this application. Horsepower numbers are purely speculation, as Edmunds insists that the truck be strapped to an all-wheel drive dyno, that way the numbers are accurate as to what it’s at on the street. The crew at Pressurized is hoping for some high five, low six hundred horsepower numbers though.

The factory CTIS was retained with the new wheel/tire package. All four wheels are able to be aired up and down via switches in the cab from the on board air system.
Rolling stock consists of 22×10.5 SOTA (formerly BMF) wheels in death metal finish.
The peanut butter and black color scheme was carried over to the rear cargo area which has enough storage for most any excursion.
A custom center console was fabricated between the backseats to hold small items secured.

With all of that extra go under the hood, the transmission would surely need some help getting all that power to the ground and getting the twelve thousand pound beast moving. The Allison 1000 was pulled and rebuilt by Terry Brown using all Suncoast Converter’s internal upgrades. The list includes upgraded clutches as well as the full list of billet internals (input, intermediate, output shaft, p2 planetary, c2 clutch hub). Once the rebuild was wrapped up, the transmission was installed with a fresh mag hytec deep pan to up the fluid capacity.

Ground clearance is as good as one could ask, and for the rest, upgraded skid plates were added to make sure everything was kept safe from debris and obstacles.

Head Turner

With the modifications wrapped up, Edmunds has put several thousand miles on his personal urban assault vehicle. The truck has been relatively trouble free, aside from the ever present gawkers rolling down the road, and the conversations it sparks up whenever it parks. Future plans are fairly simple as of now, as it’s ready to be enjoyed as is. Edmunds did mention the desire to possibly mount a decommissioned fifty caliber machine gun on the roof for the wow factor. It’s safe to say that whatever he comes up with, this will not be one vehicle you want to stay in your rear view. With the upgrades this ride is packing, you won’t have to worry; it will be passing you! DW

A Fass Titanium pump was added to keep the motor supplied with plenty of fuel. Pressurized Performance fabricated the custom mount in one of the few available spaces.
The blend of form and function is apparent from the cockpit. The dash is covered in gauges and switches that display vital engine data and control vital accessories.

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