B&G placed fifth in this year's...
B&G placed fifth in this year's Engine Challenge, showing that it doesn't take exotic parts for a Mopar 360 to make plenty of power. This month we'll go inside their small-block to see how they did it.
The AMSOIL/Mopar Muscle Engine Challenge is one of our favorite events, as we get to spend a week at Comp Cams' Memphis, Tennessee, facility flogging some of the most powerful Mopar engines around on their engine dyno. This year was no different, as six contestants met the deadline and requirements to enter the Engine Challenge, each with their own theory about the best way to gain an advantage.
The winner of the 2010 challenge was determined by measuring peak horsepower and dividing it into the displacement of the motor, for a horsepower per cubic inch rating, and all but one of the engines this year exceeded the standard of one horsepower per cubic inch. As you'll see, the fifth place B&G Speed and Machine entry was a basic, economically built 360, still making an impressive 418-plus horsepower for a 1.14 horsepower per cubic inch rating.
Due to a mechanical issue, last year's second place finisher, Chenoweth Speed and Machine, didn't make the required dyno pulls while at Comp. Claiming a total displacement of only 279 cubic inches, this would have been the smallest engine in the contest, and although we didn't get to see its potential during the 2010 contest, we'll still take a look at their combination.
Using a Mopar 273 as a basis...
Using a Mopar 273 as a basis for their entry, we were eager to see how much power the Chenoweth Speed and Machine engine would make. Unfortunately a mechanical issue kept them from making any pulls on Comp's dyno.
Every year the contestants...
Every year the contestants chosen for the AMSOIL/Mopar Muscle Engine Challenge have from mid-February until the Mopar Nationals to build their engines, and then they're all taken to Comp to be tested on the engine dynamometer.
The event draws a crowd as...
The event draws a crowd as these engines push the limits of pump-gas Mopar power.
Each engine is torn down after...
Each engine is torn down after its dyno pulls and inspected to ensure compliance with our published rules. Displacement was especially important this year, as the engines were judged on peak horsepower per cubic inch.
B&G Speed and Machine Bargersville, Indiana
Each competitor in this year's contest had their own theory about the best displacement given our rules, but B&G Speed and Machine simply relied on one of the best ways to make small-block power, a solid 360. Knowing that the RHS heads were a great match right out of the box for a Mopar 360, engine builder Bill Hess planned his combination around that match. On the dyno, the crew made a solid showing after sorting out an electrical misfire, making a best judged pull of 418.7 horsepower from their 367.2 cubic inch small-block.
Starting off with a used 360 block, B&G bored the casting .040 over, using a stock crankshaft with a stroke of 3.58 inches. Eagle forged steel connecting rods combined with economical Speed Pro hypereutectic cast pistons rounded out the bottom end, which was balanced as well. A Chet Herbert solid flat tappet camshaft was used arriving at .528 inch intake and .550 inch exhaust lift, and 255 degrees of duration at .050 inch lift.
The B&G Speed and Machine...
The B&G Speed and Machine crew were newcomers to our annual event, placing Fifth by efficiently tuning their 360 to 1.14 horsepower per cubic inch.
The B&G entry performed well...
The B&G entry performed well on the dyno, making all its required pulls and netting well over one horsepower per cubic inch while running on Rockett Brand 93 octane specially blended gasoline.
Starting with a factory 360...
Starting with a factory 360 block, B&G bored the block .040 over and filled it with a factory 360 crank, Eagle connecting rods, and Speed Pro pistons.
To top their solid short-block, B&G used the required RHS/Indy X heads, with shaft mounted rockers and LA intake pattern. These heads are a direct replacement for older Mopar small-blocks, offering improved flow, bigger valves, and a far better combustion chamber design than factory heads. To achieve better flow, these heads were fitted with large 2.05 intake and 1.60 exhaust valves, actuated by factory 273 adjustable rocker gear. For induction, an Edelbrock Victor 340 intake manifold was combined with an 800-cfm Holley double-pumper. Good for over 418 horsepower on pump gas, this 360 would make any Mopar a fun ride.
Engine parts for Mopar small-blocks...
Engine parts for Mopar small-blocks are more reasonably priced than ever, so it makes sense to replace connecting rods and pistons when rebuilding. These Eagle rods are way tougher than the originals and come with high-strength fasteners, and the Speed Pro hypereutectic cast pistons offer good strength for the price.
Chenoweth Speed and Machine Morton, Illinois and LaRoy Engines Challis, Idaho
Last year Chenoweth Speed and Machine and LaRoy Engines were competing against each other in our dyno contest, placing second and third respectively. No doubt noticing each other's strong points, Jim LaRoy and his sons teamed up with Dale and Mike Chenoweth this year, performing much of the cylinder head porting and valve work required to achieve maximum flow numbers. Using a 273 as the foundation for their build, the Chenoweth/LaRoy 279 cubic inch small-block would have required the least amount of horsepower to win the contest, since it was the smallest engine entered.
During the bench racing and idle chatter around our trailer at the Mopar Nationals, we learned that the Chenoweth/LaRoy entry had encountered a cooling system problem during dyno testing, but that the team had pulled the heads and replaced suspect head gaskets to repair the issue. Unfortunately, it reared its ugly head again once the engine was started and brought to temperature at Comp. Noticing water blowing from the dyno exhaust connection, the crew shut down the engine to investigate. Pulling the spark plugs, the problem became apparent as coolant was found in the number seven cylinder. Deciding not to risk further damage, the team chose not to make their dyno pulls, disqualifying themselves from the competition. We certainly would have liked to see this little engine run, as it could very well have been a contender in the 2010 AMSOIL/Mopar Muscle Engine Challenge had it not been for the problem.
Knowing that you don't have...
Knowing that you don't have to run a roller cam to make respectable power, B&G chose a solid flat tappet camshaft, proving that flat-tappet cams work very well in a Mopar 360.
The RHS/Indy cylinder head...
The RHS/Indy cylinder head is a great design, derived from research performed by Indy during a previous contest.
Available in both LA and Magnum...
Available in both LA and Magnum versions, B&G chose the LA versions to utilize a set of factory shaft-mounted adjustable rocker arms.
Keeping with the budget theme,...
Keeping with the budget theme, this 360 utilized a second-hand Edelbrock Victor 340 intake manifold, and a refurbished Holley 800 carburetor. This B and G team hit a good combination, without costing a fortune. Had cost been factored in this year's contest, these guys surely would have turned in a better finish.
We congratulate B&G Speed...
We congratulate B&G Speed and Machine on their performance in this year's Engine Challenge and look forward to seeing them in future dyno contests. See video of these engines running on Comp's dyno at
www.moparmusclemagazine.com.
Chenoweth Speed and Machine...
Chenoweth Speed and Machine and LaRoy Engines, last year's second and third place finishers, teamed up this year, building the smallest displacement engine of the contest and hoping for a win.
The Chenoweth/LaRoy entry...
The Chenoweth/LaRoy entry appeared to be well-prepped, so the team filled the engine with AMSOIL 10W40 and confidently rolled the little small-block into the dyno cell.
On the dyno, this 279 cubic...
On the dyno, this 279 cubic inch small-block sounded crisp as it came up to temperature, but as the coolant pressure began to rise the engine developed a noticeable miss, and coolant began leaking from the left side dyno exhaust.
A check of the spark plugs...
A check of the spark plugs revealed coolant in the number seven cylinder. Since the contest we've learned that the extensive porting performed accidently interfered with a water jacket near the number seven exhaust port.