In 1999 Burnsville Off Road owner Dan McKeag competed in Top Truck Challenge with a bright red Wrangler TJ powered by an 8.0L Viper V-10 engine. It was 488 cubic inches of g-force goodness that was so wrong it was right. Even now, 10 years later, we still get an adrenalin surge when we think of the incredible ride we took in that rig on the winding roads in the Hollister Hills.
Fast forward to 2009. McKeag is still stuffing big engines into little Wranglers. Nowadays his shop in Burnsville, Minnesota, specializes in fitting the versatile Hemi V-8 into Wrangler JKs. Here's a riddle: What does the United States, China, Australia, Canada, Germany, Oman, Saudi Arabia, Indonesia, Mexico, Chile, Brazil, England, Italy, Russia, France and the United Arab Emirates have in common? Answer: They all have customers that have taken delivery of Hemi-converted Wranglers from Burnsville Off Road. As a matter of fact, at the time this story was written the team at Burnsville had built 158 Hemi JKs and that number increases by the week.
We recently had the opportunity to spend a day at Burnsville Off Road to see how the process of converting from V-6 to Hemi works. Burnsville offers a variety of Hemi conversions featuring a choice of 5.7-, 6.1-, 6.4-, 7.0- and 7.2-liter Hemi engines with either an automatic or manual transmission. Huh? Did we say manual? Yep, it's a beefy six-speed and the installation is a Burnsville exclusive. As you can imagine, the Hemi doesn't just saunter over to the JK, open the hood, and jump right in. Installation is a time-consuming process and most folks don't have the time or patience for a swap like this. McKeag says that 90 percent of his customers choose to have Burnsville complete the install.
To facilitate illustrating how they complete the conversion, the team at Burnsville developed a few "stations" for us to visit so we could see the highlights of a typical conversion in just a few hours. Here's how it works.
On the day of our visit the team at Burnsville was prepping this 7.0L Hemi for installation into a customers rig. It's a NASCAR-grade SRT 6.1L block that has been bored and stroked by an outside vendor that Burnsville uses regularly. Its standard features include a Callies Performance Products crankshaft, JE pistons, Eagle connecting rods, and ARP hardware. If even more power is desired, options include stuff like CNC ported and matched heads, upgraded camshafts, headers, nitrous systems, and ported and matched intakes.
Technician Brian Ament went...
Technician Brian Ament went to work assembling the engine. He has assembled more engines than most people have seen in their lifetime. He began by installing the camshaft and then the timing assembly and heads. Here you can see him installing one of the pushrods. The Hemi engine uses 16 valves and a dual-plug design. The cam is mounted high in the engine so the pushrods are short.
The intake and exhaust rocker...
The intake and exhaust rocker shafts went in next and were torqued to spec. Once again, these are new OEM parts. As you can see, this engine was assembled using the stock exhaust manifolds, but headers are an option.
Here are all the parts that...
Here are all the parts that are bolted onto the engine. Burnsville installs only brand-new components.
The valve covers went on next....
The valve covers went on next. Another neat Hemi factoid is that the covers utilize an integrated rubber gasket that can be reused.
Next up was the intake. It...
Next up was the intake. It too uses a reusable gasket. Burnsville says the bolts that hold the intake are pretty small, so torque specs need to be adhered to and there is a tightening pattern for their installation.
Here's the 7.0L close to being...
Here's the 7.0L close to being completely assembled. In its standard form this specific engine produces a dyno-proven 600 hp and 610 lb-ft of torque at the flywheel.
We moved to another station where a 7.0L was already married to a 545RFE automatic transmission and the assembly was ready to set in the engine bay. Burnsville uses the 545RFE for those who wish to have an automatic transmission, but they'll soon offer the Mercedes-designed WA580 automatic transmission as well. The Burnsville-exclusive six-speed manual transmission we mentioned earlier fits as the result of a significant amount of R&D. It has undergone a variety of parts changes to enable it to mate and work with the Hemi, but all of the parts are available over-the-counter for ease of ownership. One of the biggest challenges in getting the six-speed to work was on the electronic side of things. We'll get to that a little later on.