Nothing says Mopar muscle...
Nothing says Mopar muscle power like a big Max Wedge cross-ram. Our 505-inch version is shown here waiting for the ride to the dyno where it cranked out 625 hp and 610 lb-ft of torque.
The big cross-ram manifold...
The big cross-ram manifold is the business end of the Max Wedge. We topped it off with a pair of 800-cfm Edelbrock carbs and a Mancini Racing linkage kit.
This view from the rear shows...
This view from the rear shows how the 15-inch long runners inside of the MP manifold cross over from one side to the other. The right-side carb feeds the left-hand head and vice versa. Also visible in this picture is the gap under the manifold. The Indy heads raise the intake up into the air about 0.500 inch, so you'll have an air gap between the valley cover and the bottom of the intake.
The cross-ram is such a big...
The cross-ram is such a big manifold that it hangs out over the valve covers. We put ours in a Bridgeport and trimmed some excess material off in order to provide access to the tall Indy covers. If you don't remove these ears you won't be able to install or remove tall valve covers with the intake installed.
These Indy EZ heads with full...
These Indy EZ heads with full CNC porting flow 350 cfm at 0.700-inch valve lift on our little Superflow 110 flow bench. That's good enough for 700 hp if everything else is up to par.
The History
We all know the Max Wedge is an all-time classic that roared out of Detroit in 1962. With that big, honking, dual-carb, cross-ram intake, the upswept exhaust manifolds, the radical cam, and the high-compression pistons, the Max Wedge motors made a reputation that has lasted over 40 years. The Max Wedge cranked out 425 hp back in the day when daily-driver motors were barely making half of that, and you'll still find them screaming down the quarter-mile at most any Mopar meet today.
We've wanted to recreate one of these legendary motors for some time, but the special parts required were just a little too expensive for our pocketbook. So when we discovered that Mopar Performance released a reproduction of the original cross-ram intake manifold, we jumped at the chance to finally build our own Max Wedge. Of course, we couldn't leave well enough alone, so while we were at it we made our version bigger and better. By the time we finished, we had 505 inches and 625 hp in our hands.
The Plan
The goal we had was to make a modern version of the '63 Max Wedge. We wanted to maintain the big cross-ram with the dual AFB carbs, the 13.5:1 compression, the Max Wedge ports, and the big flat-tappet cam. But we felt the improvements made in cylinder heads over the last 40 years, as well as the newest options for crankshafts, connecting rods, and pistons, should also be incorporated. So our final plan was the old-school look filled with modern parts.
Our plan for the short-block was to stuff an original RB block with a modern stroker crankshaft since the additional cubic inches is an easy way to make more power. Either a 413 or a 426 block would have been more correct, but we decided to use the more popular 440 block as our foundation. Both the 413 and 426 blocks suffer from a smaller bore size, which really starts to limit the cylinder head breathing. The original Max Wedge engines also need to have notches cut into the cylinder block to provide clearance for the large exhaust valves, but that isn't required when using the larger 440 bore size.
What really made the Max Wedge different from all the other big-block wedge motors was the size of the intake ports. The MW used a super-size intake runner that is almost 30-percent larger than the standard port. These large-port heads were only available from 1962 to 1964, and then that port size disappeared from production. The Max Wedge cylinder head became a legend due to track performance, but since the only intake manifold available was the dual-carb cross-ram, these large port heads didn't really become very popular with the street crowd.
While the factory heads never became popular, the aftermarket recognized a good thing when they saw it. Over time, several vendors, such as Indy Cylinder Head, introduced aluminum heads and intake manifolds based on the large MW port design. The Indy heads differ from the original heads since they have raised intake runners and longer valves, but we felt they were a natural evolution of what the factory engineers started back in 1962, so we chose them for this engine build.
The new intake manifold from Mopar Performance is a fairly close reproduction of the original right down to the lettering and part numbers cast into the top. We couldn't locate a pair of original carburetors since they are few and far between, but once again, the aftermarket has stepped in with a solution. Edelbrock is currently making several new and improved versions of the old Carter carburetor, including a larger 800-cfm model that we decided to run. The throttle linkage on the new Edelbrock carb is a little different than the original Carters, but Mancini Racing carries a special cross-ram linkage kit that fits the Edelbrock carbs. So with that final part in hand, our induction setup was complete.