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The Many Flavors of Max Wedge

Also see our main Max Wedge page

These are great times for Max Wedge fans. Never before have so many cross ram choices been available for your consideration. We’re not talking about obscure swap meet oddities either, we’re talking about foundry fresh castings you can easily buy right now.

cross-ram wedge

While aftermarket sources such as Indy Cylinder Head offer loose interpretations of the cross ram for all out drag racing, this review is limited to those manifolds that seek to retain the original appearance. Half of the treat of lifting the hood on a Max Wedge is having the right look.

Before we start this review, let’s remember the hows and whys of ram tuning. In a nutshell, as each cylinder pulls fuel and air during the intake stroke, the column of fast-moving gasses has a certain amount of mass. As the piston approaches bottom dead center, the intake valve closes and the column of gasses comes to a sudden stop inside the intake tube, creating energy in the form of pressure waves that bounce back and forth between the back of the closed intake valve and the mouth of the carburetor, at something like 1,100 feet per second.

The next time the intake valve opens, there should be a pent-up wall of gasses waiting to crash the gate and fill the cylinder bore — if you tailor the valve timing just so, and if you configure the intake runner in just the right way. This provides a form of free supercharging.

It isn’t like plopping a belt driven GMC 6-71 on top of things, but it’s a proven fact that induction efficiency of as much as 108% — that’s 8% above atmospheric - can be realized. If that isn’t free supercharging, we don’t know what is. By adjusting the length and volume of the intake runners, you can tune the incoming supercharged rush to occur at specific engine speeds, thus boosting cylinder pressure and torque in harmony with the selected rpm point.

1964 Max Wedge Dodge

Back in 1960, when Chrysler unleashed the two piece long-ram induction systems on full size cars, the goal was improved low and mid range torque for quick stop light getaways and rapid highway passing. The runner length was 30-inches and the resulting torque spike occurred from 2800 rpm through about 4800 rpm. It was great for moving two-plus tons of luxury liner, but the long branches choked flow after 5000 rpm so the top end performance suffered.

1960 cross ram wedge

But when Chrysler got serious about entering the Super Stock fray in 1962, they knew top end breathing was more important than passing power on the highway, so they reduced the runner length to 15 inches, tuning the resulting one piece cast aluminum manifold for 5400 rpm. The Max Wedge was born.

The original cross ram is very well suited to a 413 cubic inch engine spinning at 6500 rpm. When they upped displacement to 426 in 1963 and 1964 to take full advantage of the 7 liter cap imposed by NASCAR, the manifold still worked well. But as racers got creative and started using 488-cube stroker cranks and stepping up the cam and valve springs for 7000 rpm rev capability, the cross ram quickly got in the way and choked power.

With the 426 Race Hemi due on the scene for 1964, factory Max Wedge development ground to a halt. Word is that Barney Navarro — perhaps with assistance from Chrysler - cast some wild cross ram intake manifolds with four Carter AFB caburetors in place of the usual two. Max Wedge guru Bob Mazzolini supposedly has one of these crazy quad quad Maxie manifolds. But Hemi fever was on and after mid-1964, the Max Wedge pretty much slipped into obscurity for the next four decades, a swap meet relic.

In recent decades, more and more people are rediscovering the Max Wedge and want to tap into the mystique of the Orange Monster. Simply put, if you are doing a Max Wedge clone, you simply must get a cross ram. There is no place for single quads — even though many are capable of outperforming the mighty Max Wedge, all other things being equal. Sometimes looks are more important than raw performance.

Original story and additional photos: http://www.moparmax.com/features/2008/iii_2-wedge-1.html

Also see our main Max Wedge page

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