Of all the technical subjects we write about here at Mopar Muscle, our annual engine challenge always gets a great response, and why not? Where else can you see eight of the country's best engine builders compete head to head exclusively with Mopar iron, with true dyno numbers to back up their proven combinations? Since our challenge factors not just the power of each engine, but also the cost of the each engine's parts, the builders have to be creative to be competitive.
This year, our engine challenge features the small-block Chrysler powerplant, and we've already chosen the eight engine shops that will compete. We look forward to seeing what kind of numbers their potent LA engines will produce.
David Bruns and his wife,...
David Bruns and his wife, Dianne, of Mid America Racing Engines took home top honors in last year's Mopar Muscle engine challenge with their stout big-block that churned out more than 741 hp. David will compete again in this year's challenge, which will feature the small-block Chrysler engine.
This year's engine challenge...
This year's engine challenge will feature the potent small-block Chrysler LA powerplant, with displacement limited to 410 ci.
Comp Cams will again host...
Comp Cams will again host our engine challenge, providing personnel as well as their dyno cell for our competition.
| Diamondback Engines|
7723 FM 723
Richmond, TX 77469
| Indy Cylinder Head|
8621 Southeastern Ave.
Indianapolis, IN 46239
| Mid America Racing Engines|
1945 W. 18th St.
Washington, IA 52353
| MRL Performance|
4651 Culley Ln.
Jackson, MI 49201
| Muscle Motors|
2085 Glenn St.
Lansing, MI 48906
| R.M. Competition|
Roseville, MI 48066
| Schurbon Engine and Machine|
203 S. Clark St.
Maquoketa, IA 52060
131 W. Lang Ave.
West Covina, CA 91790
Rockett Brand Racing Fuels...
Rockett Brand Racing Fuels will again be sponsoring our challenge, as well as providing their specially blended 93 octane pump gas for the contest.
Any production steel block...
Any production steel block will be allowed in this year's small-block engine challenge. maybe a future contest will allow more exotic hardware such as the Mopar R3 block shown here.
Our rules regarding cylinder...
Our rules regarding cylinder heads are far less restrictive than in previous contests, so we could see some exotic combinations this year.
Either flat-tappet or roller...
Either flat-tappet or roller camshafts are allowed this year, but ceramic lifters are not allowed. Lifters are limited to factory .904-inch diameter.
If you've followed our previous engine challenges you're already familiar with the basic rules. Each engine must qualify by making three, nonscored dyno pulls during a 45-minute period. Tuning and repairs may be made during this time, as long as three pulls over the full span of 3,000 to 7,000 rpm are made. After the qualifying pulls, the builder will be given 10 minutes to inspect his or her engine before making the dyno pulls that will be scored for the competition. Three required scored pulls must be made in the second 45-minute session, and tuning is allowed between pulls as long as three complete dyno pulls are made during the 45 minutes. We then take the scored pull with the best combined peak torque and horsepower, and factor the cost of the parts into the power for a horsepower-per-dollar factor. Manifold vacuum will be used as a bonus rating, and one point will be awarded for each inch of manifold vacuum at 1,000 rpm. So if the competition is close, the engine with the most vacuum will win the position.
Since there are literally hundreds of block and cylinder head combinations for the small-block Mopar, we decided to open the rules up a bit for this year. Engine displacement will be limited to 410 ci, and the block must be a production, cast-iron block or replacement block. The crankshaft must be either cast or forged steel, and only steel connecting rods will be allowed. No lightening of the crankshaft will be allowed. Pistons must be catalog, off-the-shelf units with factory size ring grooves. since there is no restriction on compression ratio, engine builders will likely push the limits based on the Rockett Brand 93 octane pump gas we'll be using for the challenge.
Because there are so many cylinder head options for the small-block Mopar, and in the interest of big power numbers, we decided to be less restrictive with this year's cylinder head rules. Instead of providing headers for the competition, we're requiring the engine builder to supply his or her own headers to match the cylinder heads on their engine. We're still only allowing production, Mopar-style cylinder heads, and we won't allow welding or epoxy modifications to the heads, but otherwise cylinder head selection is up to the engine builder. We look forward to a diverse selection of cylinder heads as builders will certainly utilize varied techniques to gain an advantage.
We're limiting induction to a maximum of 1,000 cfm this year, which should be plenty of fuel and air for these small-blocks to make big power. There is no limitation on the number of carburetors, so dual quads or six-pack induction is legal. Power adders, however, will not be allowed since our plan is to show how much power the small-block can make in a normally aspirated form. While we're pretty sure most builders will use large, single-plane intake manifolds for maximum power, we can't help but wonder if anyone will use stock induction to keep costs down.
There are really no camshaft...
There are really no camshaft restrictions in this year's challenge as either roller or flat-tappet cams are allowed. Lifters must be .904-inch diameter, the same as factory lifters, and ceramic lifters will not be allowed. The cam must be driven mechanically by either a timing chain or geardrive, with no beltdrives allowed. Otherwise, specifications such as lift, duration, and lobe separation will be left to the individual engine builders.
If you're going to attend the Mopar Nationals in Columbus this year, plan a trip by the Mopar Muscle trailer to see all the entries in this year's contest. Engine builders will be on hand to discuss their techniques and can likely answer questions about your next engine project as well. Last year, our display drew quite a crowd as some of the best engine builders in the country eagerly shared their engine-building knowledge with anyone who was interested.
After the Mopar Nationals, the challenge engines will be delivered to Comp Cams where they will remain until they are placed on the dyno in late September. Comp has a great facility, and their hospitality during previous engine challenges has been second to none. Every year our challenge engines have made more and more power on Comp's dyno, and we hope this year is no different. Even with fewer cubes to work with, we won't be surprised to see horsepower numbers well above the 700 mark.
If you've run a small-block Mopar in one of your cars, then you certainly know the potential of this great engine. If you're a devout big-block or Hemi enthusiast, this year's contest might change your mind about the potential of the Mopar small-block. As our contest gets underway, be sure to stay tuned to future issues where we'll not only tell you who won, but also go inside each engine in depth, outlining the combinations that worked, as well as those that came up a little short. Also, if you're in the market for a new engine, be sure to contact one of our engine builders. These guys know Mopar engines and can certainly help with your next project.
Total induction volume is...
Total induction volume is limited to 1,000 cfm and is not limited to a single four-barrel. All engines must be normally aspirated, however, meaning no nitrous, blowers, or turbos are allowed!
All of the engines in this...
All of the engines in this year's challenge will be on display at the Mopar Nationals, where engine builders will be on hand to discuss their techniques with our readers. Mopar Muscle publisher Jim Foos will also be on display at the Mopar Nationals and will happily answer any questions our readers might have about the magazine!
After the Mopar Nationals,...
After the Mopar Nationals, all of the challenge engines will be delivered to Comp Cams dyno facility in Memphis, Tennessee, where they will be quarantined until they go on the dyno in late September.
The dyno doesn't lie, so we're...
The dyno doesn't lie, so we're interested to see how much power these small-blocks will make. Editor Bolig thinks the small-blocks have big potential, but this author doesn't believe they'll top the big-blocks in last year's challenge. One thing's for sure though, it'll be fun finding out!
After the dyno, each engine...
After the dyno, each engine will go through a technical inspection by our staff to ensure compliance with the contest rules.