Prism Racing scored a win in one of the closest Engine Challenges we’ve had as their 406 i
When it comes to making a Mopar fast, it doesn’t matter what body style your car is, or the transmission or rear end ratio it’s equipped with, if it doesn’t have a powerful engine, you’ll likely be disappointed in the performance. Since the inception of the AMSOIL/Mopar Muscle Engine Challenge, we’ve focused the rules of our contest on real-world street engines built to make big power on pump gas. This year, we challenged the engine builders in our contest to put together a big-block Mopar engine that would run on Rockett Brand 93 octane gasoline, while remaining within a parts budget of $5,500.
Seven engine builders met the deadline for this year’s Challenge, delivering their engines to the Mopar Nationals where they were on display for the weekend, and then quarantined and taken to the dyno cell at Comp Cams’ Memphis, Tennessee, research facility. The engines were then tested on the dyno in random order. To judge the engines in this year’s contest, we chose to use one of the oldest standards, horsepower per cubic inch. Each engine had to make a minimum of three qualifying dyno pulls, and then three judged pulls. The highest peak horsepower achieved during the judged session was divided into the displacement of the engine. To ensure the contestants remained within our $5,500 parts budget, a 10 horsepower deduction was applied for every $100 the budget was exceeded.
After running on the dyno, each engine is torn down to ensure rules compliance. This year
With these rules in place, most of the competitors chose to remain well within the budget, and really sharpened their pencils to come as close as they could without exceeding $5,500 retail cost for the major parts of the engine. Of course we didn’t calculate the cost of each nut and bolt, but all major engine components were factored into the budget. For a full list of the parts used for this calculation, visit www.moparmusclemagazine.com, where you can also see the complete rules for the contest as well as videos of the engines making dyno pulls.
After making the dyno runs at Comp, we tore down each engine to inspect it for legality, and also to ensure the parts in the engine were the same as the engine builders listed on their tech sheets. With the dyno numbers and inspections complete, we then used a third party source to calculate the retail cost of the parts in each engine, and added the cost of the factory parts at fair market value. The allotted price of the factory parts was listed in the rules, and most engine builders utilized a factory block, crankshaft, and even cylinder heads to remain in budget. With our calculations complete, this month we’ll feature the engines in the order they placed.
We know you’ll join us in congratulating Prism Racing, as they carefully interpreted our rules to build an engine within budget, making nearly 1.6 horsepower per cubic inch, to capture a win in this year’s challenge. Engine builder Darren Tedder spun his 406 cubic inch low-deck big-block to nearly 8,500 rpm to achieve his goal, narrowly beating T & B’z Race Engines for the top spot. All but two of the engines remained within budget, with the Mid America Racing Engines entry being the most economically built big-block in the contest. Also worthy of note was the LaRoy Engines entry which was over budget, but impressed everyone by making 730 horsepower using factory 906 casting cylinder heads ported by Cody LaRoy.