We'd all love to be able to build and test multiple engine combinations on the dyno before deciding which engine is right for our Mopar, but most of us just don't have the resources (i.e. the cash) to perform this type of testing. Fortunately, the AMSOIL/Mopar Muscle Engine Challenge offers our readers the opportunity to compare eight different engine combinations without spending a dime more than the subscription rate. Even better, the engines competing in our contest are dyno'd at Comp Cams' research facility and we provide all the numbers for comparison.
Each year of our annual competition we highlight a different Mopar engine, and vary the rules of the contest just to keep things interesting. We also test the engines using Rockett Brand 93 octane gasoline, which forces the competitors to build engines that will run on fuel with a similar octane rating to what they can get at the local station right out of the pump. For the 2011 contest we decided to judge the motors in a similar manner as last year, horsepower per cubic inch, but added an additional twist to keep the price of these engines within the reach of the average enthusiast. In addition to factoring the peak horsepower of each engine into the engine's displacement, the engine builders were allowed a maximum budget of $5,500 for the parts in their big-block.
For some of us $5,500 is a lot of money, but in today's world it is actually a reasonable parts budget for an engine build, especially considering the amount of power this year's contestants made. And while our rules did allow the engine builders to exceed the budget limit if they felt they needed to, they would be docked ten horsepower for every hundred dollars they went over, which encouraged them to remain within the budget. While we did want the engine builders to show what kind of power could be made for a reasonable price, we didn't necessarily want junk yard motors in the contest so there was no benefit for using less than the allotted amount for the engine parts.
So with an interesting set of rules in place, we chose eight competitors for this year's contest. Seven of the eight made our deadline, delivering their engines to the Mopar Nationals where they were displayed for the weekend. We were pleasantly surprised at the diversity we saw in these engines, with displacements from just over 400 cubic inches to slightly less than 500 cubic inches. Additionally, some competitors utilized factory cast-iron cylinder heads while others chose aftermarket heads from Indy, Edelbrock, and 440Source. With the engines at Comp's Memphis, Tennessee, research facility, we filled each of them to the pan's capacity with AMSOIL's Z-Rod 10W30 synthetic motor oil, and ran them one at a time in random order to see just how much power they would make.
During the test session, each engine builder had to qualify their engine by making a minimum of three dyno pulls from 3,000 to a minimum of 7,000 rpm in a 45 minute time period. Tuning was allowed during this session, and all of the engine builders took advantage of their time to make carburetion, ignition timing, and valve lash adjustments. After the qualifying session, each engine had to make a minimum of three dyno pulls during a 45 minute judged session, again from 3,000 to a minimum of 7,000 rpm. Noting that there was no upper limit to the rpm scale, a couple of the engine builders made pulls well above the 7,000 rpm minimum in order to make their peak numbers. This month we'll show you how the first four engines performed in our contest, and give you a rundown of the parts used in each of the engines. Be sure to follow future issues of Mopar Muscle as we show you the results of the three remaining engines as well as publish a parts list and dyno sheet for each of the engines in 2011 AMSOIL/Mopar Muscle Engine Challenge.
Comp Cams hosts the dyno portion of our Engine Challenge, and each engine is tested for bo
While on the dyno at Comp, each engine is run with AMSOIL’s new Z-rod 10W30 synthetic moto
After choosing the competitors from applications submitted, we chose eight engine builders
T & B’z Race Engines entered our competition for the first time this year, bringing a 426
T & B'z Race Engines
As a newcomer to our contest, T & B'z Race Engines read and interpreted our rules carefully, using a sleeved, factory-Chrysler 400 block with bushed lifter bores and a factory 3.75-inch stroke 440 crankshaft to achieve a displacement of just over 426 cubic inches. Eagle H-beam connecting rods and Diamond forged pistons were utilized as well and Engine builder Tom Foley had enough money in his budget for a Comp custom solid-roller camshaft and lifters. Aluminum Stealth cylinder heads from 440Source were ported in-house, and Harland Sharp 1.6 ratio rocker arms were used to actuate the valves. For induction, an Edelbrock PN 2886 single-plane was matched with a Barry Grant four-barrel carburetor.
Engine building and tuning is a family affair for the Foley’s, and along with wife Brenda
On the dyno, engine builder Tom Foley along with his wife Brenda and their four kids all pitched in to help with the tuning, making jet changes during the qualifying period and making dyno pulls with and without an air-hat on the carburetor. During the scored dyno session, Tom adjusted jetting, changed the spark plugs, and replaced the oil pressure spring to lower the engine's oil pressure and free up a little power. Pulling the engine to 8,000 rpm, the 426 big-block made 675.6 horsepower at 7,200 rpm for a rating of 1.586 horsepower per cubic inch. Once we factor the cost of this engine to ensure it remained under budget, we feel this will be a very competitive number and certainly impressive for a pump-gas engine.
Bill’s Speed and Machine built a 451 cubic inch low-deck big-block for the 2011 Engine Cha
Bill's Speed and Machine
Having competed in last year's dyno contest, engine builder Bill Hess of Bill's Speed and Machine had a good idea about what it takes to be competitive in our dyno challenge. Knowing the budget would limit the money he could spend, Bill spent frugally on his short block, using a factory 400 block and 440 forged-crankshaft with Eagle connecting rods and Speed Pro pistons. To top his 451-inch engine, Bill chose SR cylinder heads and a single-plane intake manifold from Indy Cylinder Head, Harland Sharp roller rocker arms, and a Holley vacuum secondary four-barrel carburetor.
Tuning his engine on Comp's dyno, Bill Hess made several carburetor jet changes to richen the fuel mixture of his engine during the 45-minute qualifying session. After his third qualifying pull, Bill removed the one-inch aluminum carburetor spacer and added a three inch open spacer and then moved directly to his judged dyno pulls. Reading his spark plugs, ignition timing was backed down 38 degrees total advance, then again to 36 degrees where the engine made its best power. By jetting even richer, the Bill's Speed and Machine entry made its best horsepower number of 623.2 at 6,500 rpm for a 1.38 horsepower per cubic inch factor. With over 557 lb/ft of torque, this is a real-world street engine that would perform great in any Mopar.
Engine builder Bill Hess made good tuning decisions during his dyno pulls, netting additio
Each engine is torn down and inspected after its dyno runs to ensure the displacement and
As a previous winner of the AMSOIL/Mopar Muscle Engine Challenge, Mid America Racing Engin
Mid America Racing Engines
Engine Builder Dave Bruns has consistently shown his ability to not only make power, but to build economical and reliable Mopar engines as well. For the 2011 contest the Mid America entry used the somewhat unconventional combination of a factory 383 block with a factory forged 413/440 crankshaft offset ground to a stroke of 3.90 inches. 440Source pistons and RPM connecting rods completed his rotating assembly, which was machined and balanced in-house. Staying away from expensive roller camshafts, Bruns utilized a Cam-Motion solid, flat-tappet cam with a gross lift of over .650 inch. 440Source aluminum Stealth heads topped this engine, and an Edelbrock PN2886 intake manifoldùcombined with a Holley carburetorùhandled induction.
As usual, the Mid America entry had been previously dyno tuned and needed very little work to optimize performance. While in Comp's dyno cell, Dave Bruns made minor carburetor jetting adjustments, and set the ignition timing at 38 degrees total advance for his big-block to make its best power. At 450-inches we expected this engine to make great torque and it did, peaking at 554 lb/ft at 5,300 rpm. Peak horsepower came on the fifth scored dyno pull, with the engine making 622.2 horsepower at 6,700 rpm. We're confident that this engine remained under our budget of $5,500, and at 1.38 horsepower per cubic inch the Mid America Racing Engines entry is a budget big-block that really performs.
On the dyno, engine builder Dave Bruns made minor adjustments to the ignition timing and c
Tearing down the Mid America entry proved that this was a solid engine, as all of the inte
Engine builder Buck Hinkle of Hinkle Performance is new to the Engine Challenge, but has c
Competing for the first time in our annual contest, Hinkle Performance calculated that a small displacement engine would give them an advantage since the winner this year will be determined by horsepower per cubic inch within a budget. Using one of the smallest factory blocks, a 361, engine builder Buck Hinkle carefully spent his budget, using a factory 361 crankshaft and less expensive Eagle Rods for a Ford Modular application. Mahle pistons for a small-block Chevrolet were also employed for their light weight and to save money, and a Comp solid flat-tappet cam and lifters actuated the valves. Topped with ported factory "915" casting cylinder heads, Edelbrock single-plane intake, and Holley carburetor, this engine definitely remained under budget with the potential for big power.
Once in Comp's dyno cell, the Hinkle Performance big-block had a little trouble firing up initially, and once running one of the crew commented that the big-block didn't sound quite like it did on their shop dyno, but attributed the difference to dyno cell configuration. After a brief warm-up, the Hinkle crew began their qualifying pulls, tuning their engine and making additional power by swapping the one-inch open spacer for a one-inch four-hole spacer, then removing their 950cfm carburetor and replacing it with a Holley 1000 cfm unit. Before their forth qualifying pull, ignition timing was moved to 38 degrees and the engine made its best pull of 595 horsepower. Unfortunately, during the next pull the engine experienced a catastrophic failure as the head of an exhaust valve broke from the stem at 6,800 rpm, destroying the number two piston and the block. Was it not for the failure, this engine was on its way to being very competitive, making 1.47 horsepower per cubic inch.
Engine builder Buck Hinkle and the crew from Hinkle Performance brought the smallest big-b
This was the first catastrophic failure in the seven years of our contest, and it was a bi
We hope you enjoy reading about the engines in the AMSOIL/Mopar Muscle Engine Challenge as much as we enjoy writing about them, and encourage you to contact one of these professional machine shops for your next engine project. Next month we'll highlight the last three engines to run in our contest, and will announce the winner once we determine which engines remained within our parts budget of $5,500. So far this has been one of the closest contests to date, and we promise you don't want to miss our next three engines to see some incredible power numbers, and rpm. Be sure to check out moparmusclemagazine.com as well to see video of each big-block making pulls on Comp's dyno.