Whether you're into classic or late-model Mopars, there's no doubt that the new 5.7, 6.1, and 6.4 Hemi engines can provide the power to satisfy any enthusiast's need for speed. Though small in displacement when compared to muscle car engines of the '60s and '70s, these new Hemi engines incorporate many features such as roller camshafts and aluminum cylinder heads that just weren't available from the factory on Mopar muscle cars. For this reason, we're seeing more and more late-model Hemi engines not only in LX platform Mopars, but in classic Mopar street and strip cars as well.
When it comes to transplanting Chrysler's new Hemi engine into a vintage Mopar, there are several obstacles that stand in the way. Exhaust, engine mounts, and oil pans are the first considerations, but these issues have been resolved by forward thinking companies eager to embrace the new Hemi engine. TTI now provides headers not only for LX cars with the new Hemi, but for popular classic Mopars as well. And if you're using TTI's headers for your swap, we suggest using their conversion engine mounts as well. Milodon has also stepped up, manufacturing oil pans and systems to make the new Hemi fit classic Mopar body styles with ease. Since the new Hemi was manufactured with coil-on-plug ignition, a decision needs to be made when swapping the new engine into older body styles. While there are distributor conversions available, we've found that MSD's new ignition system does a great job of running the individual coils, without the need of a distributor.
A big issue with swapping a late-model Hemi into an older Mopar has always been the induction system. Our older Mopars are equipped with a fuel system designed for a carburetor (or multiple carbs), and just won't support modern fuel injection. Sure, you can completely modify your car's fuel system with a high-pressure pump, modified fuel tank, return line, and all the necessary electronics to support fuel injection, but there is an easier way. Indy Cylinder Head has designed an intake manifold that not only allows a carburetor to feed the late-model Hemi, but allows for the easy swapping between a single four-barrel, dual-quads, Six Pack, or even a blower. Called the Mod-Man, this intake system revolutionizes feeding a new Hemi with carburetors, and even has provisions to mount the coils on the bottom of the intake for a super-clean look.
Indy's Mod-Man intake is available for many Mopar engines, including the late-model Hemi, and is really a great way to give you options when it comes to installing a new Hemi into an older Mopar. The idea is simple: Manufacture one intake manifold with multiple tops for the various carburetors that are popular with Mopar enthusiasts. If you want the simplicity of a single four-barrel, the Mod-Man can accommodate you. By simply changing the top plate of the intake, you can also bolt up a trio of two-barrel Holleys, or dual four-barrels of your choice. Want over the top looks and power? By attaching the blower top to the Mod-Man you can also supercharge your new Hemi with ease.
We were recently in Indianapolis, and bolted a 6.1 late-model Hemi to the dyno and tested three different tops on the intake. With the Mod-Man already on the engine, we were impressed by how easy and quick it was to swap between the single four-barrel, Six Pack, and dual-quad tops. To reduce the number of fasteners necessary, the Indy design team actually uses the carburetor attaching bolts (or studs) to hold the top to the intake manifold. We easily had all three systems tested in about a half a day, getting horsepower and torque numbers for each configuration.
The engine we used for our testing is a 6.1 Hemi with a stock bottom end, a Milodon oiling system, and is available as a crate engine from Indy's catalog with either stock or CNC ported cylinder heads. A pair of Indy's CNC ported 5.7 heads topped this engine we tested, and Indy advertises this combination on their website at 435 horsepower and 410 lb-ft of torque when equipped with dual four-barrel carbs. We were eager to see if this engine could back up their claims, and when our dyno session was over, the Indy 6.1 Hemi crate engine with a stock SRT8 camshaft easily exceeded these numbers. Even more impressive, when the Six Pack and single four-barrel were installed, power and torque both remained high. We know you're likely asking why Indy didn't use the 6.1 cylinder head for this application and the reason is simple. 5.7 Hemi heads are less expensive and far more readily available, and with CNC porting they don't have any problem flowing enough air for serious power.
Indy Cylinder Head can provide just the intake manifold, or the intake, carb(s), and even the linkage required as a complete package. We love the optional Six Pack and dual-quad setups, as they not only provide a nostalgic look but improved power over the single four-barrel as well.
The Cash Outlay
PartCost Mod Man Intake Manifold with choice of tops, gaskets, and hardware$499 Additional Top Plates$135 each
