One of the best things about building a truck with 2 1/2-ton Rockwell axles is being able to throw obnoxious amounts of power at them. That's not to say they'll never break, but they're certainly not a weak link either.
With the factory powertrain plucked from our '99 Dodge Durango (aka Monster Mudder, aka Heavy Metal Mudder), we went searching for new horses from a completely different stable. We wanted to use Mopar muscle, but desired to do something different than a Hemi swap. So we went after the ground-shaking power from Dodge's flagship car, the Viper. Hemi engines make good power, but there is just something about a 505ci V-10 that makes us feel giddy as a fat kid at Chuck E. Cheese on his birthday.
1. After we did the initial...
1. After we did the initial drop in of the new 8.3L into the Durango we pulled out the tape measure and decided that the firewall had to be pushed back. Though we looked at relocating the radiator and other engine components forward, we found that cutting the firewall out was the right way to do it. Chris Polanski marked the original firewall and, using a cutoff wheel, began the removal.
Our first challenge was figuring out if this swap was even possible. Sure, anything's possible, but sometime's the benefit doesn't outweigh the cost. After spending some long hours on the phone with expert Viper tech Tom Sessions, we were able to determine that the 8.3L Gen III engine would be the easiest to swap in.
What makes the 8.3L the best is that it was available in the SRT-10 Dodge Ram with the automatic 48RE transmission. This meant we could easily bolt everything together, make it 4WD, and that there is a factory engine and transmission controller. We'll spend more time on the electronics in another issue, but for now we'll focus on actually getting the engine fitted inside the Durango.
At National Speed in Wilmington, North Carolina, the crew at Momentum Performance lent us a hand with some of the fabrication. Momentum specializes in twin turbo kits and high-performance mods for a slew of go-fast autos. While National Speed is a complete service shop, when it came time to recreate a firewall and build a custom set of headers, we decided to bring in Momentum to help us meet our deadline.
Be sure to check back with us next month as we continue the shoehorn process and begin making way for the remainder of the drivetrain pieces.
Engine Specs
Type: Gen III, 90-degree V-10
Displacement: 8.3L (505 ci)
Weight (lb): 625 (approx.)
Horsepower (hp): 540 @ 5,700 rpm
Torque (lb-ft): 580 @ 4,500 rpm
2. We knew that the 2 1/2-ton...
2. We knew that the 2 1/2-ton Rockwell's front third member was going to be a bit of an issue for how tall the new engine block is. Pushing the engine a little over a foot past the firewall allowed us to keep our custom multilink suspension. This keeps the Durango lower, helps balance the weight to the center of the rig, and places less mass over the front of the axle.
3. Though the Viper block...
3. Though the Viper block isn't any wider than the factory 5.9, the extra two cylinders and massive rear sump oil pan from the SRT-10 truck make the overall larger. To make the install easier we removed the front coils and the wheels from the Durango to get it as low as possible.
4. The initial fit of the...
4. The initial fit of the engine allowed us to learn a lot about what needs to be cut and how tight things will be for the headers, driveshafts, intake, and such. We borrowed an empty 48RE transmission housing from Big D's Tri County Transmission Service to mock everything up and learn how much more firewall modifications would be necessary.
5. One thing that make the...
5. One thing that make the 8.3L Gen III engines more desirable for engine swaps is the adapter plate that bolts to the back of the block. This allows the same 48RE automatic transmission that comes in the 3/4- and 1-ton Dodge Rams to bolt up with no modifications. The only catch is that you will need the flexplate from an SRT-10 truck since the camshaft bolt diameter is different from the standard diesel trucks.
6. With the engine position...
6. With the engine position determined, Momentum Performance fabricated us engine mounts that used bushing inserts from Mountain Off-Road Enterprises. Smaller engine bushings will likely equal more vibration that you can feel, but we don't see ourselves cruising the countryside in our Monster Mudder anytime soon.
7. Engine mounts were fabricated...
7. Engine mounts were fabricated that use welded nuts on the backside of 1/4-inch plate to secure the block mounts. By using an additional plate that bolts to the engine mounts, we can easily slide the engine back to the mounts and bolt it in. This is crucial since there is no way to lower the engine straight down from the top.
8. Since we no longer have...
8. Since we no longer have a firewall, a new one needed to be fabricated by Paul Murray from Momentum. He molded a new firewall out of TIG wire, tacking pieces of it together to form the new shape. Since the engine now protrudes inside the cab, Murray needed to create a doghouse-style firewall.
9. Transforming a TIG-wire...
9. Transforming a TIG-wire skeleton into a sheetmetal structure as finely tuned as this is nothing short of art. Without giving Murray's trade secrets away, we'll say that being handy with a brake and comfortable with sheetmetal are extremely important to creating a doghouse as complex as ours.
10. The doghouse is far from...
10. The doghouse is far from finished. We will need to make access holes for the engine and determine how to secure and seal it in the Durango. Another challenge ahead is relocating the accelerator and brake pedal since one of them no longer has a place.
The Viper Stork
When it comes to the Dodge Viper, few companies know more about it than Arrow Racing Engines. Arrow started more than 30 years ago to support all aspects of Chrysler Motorsports, performance parts, and production. The company was on the ground floor when the first Viper project was conceived in 1989. Now owned by Power-Tec Engineering, Arrow is the official Viper engine warranty center and has a customer engine service program that allows you to have your Gen I to Gen IV engine built and serviced. Arrow can also provide you with a complete replacement engine. In addition to a friendly and knowledgeable staff, Arrow has a huge selection of past and current Viper parts. It was our number-one source for getting everything from the correct SRT-10 throttle body to the rear sump oil pan.