Tech Q and A

I understand the new 392 HEMI® used in the 2011 Dodge Challenger SRT8® with automatic trans is equipped with a MDS unlike the 6.1L. Does the valvetrain share any parts or have any similarities with the current production 5.7L HEMI with MDS?

MM: The 6.4L (392) and the 5.7L have the same Variable Cam Timing (VCT) and Multi-Displacement (MDS) operating systems. Due to the larger displacement of the 6.4L, the valves, intake and exhaust ports, and camshaft profile are much larger than the 5.7L. This engine is the best of both worlds—good fuel economy during normal driving and tons of power whenever you need it.

I would like to put a performance chip in my 2011 5.7L HEMI-powered Dodge Charger. Will doing this hurt my engine in any way or void my warranty?

MM: Aftermarket engine programmers are not supported by Chrysler Group LLC and their use will void your vehicle’s warranty. Mopar® has a Cold Air Intake (77070044) and the Cat-Back Exhaust System (P5155958) that are both 50 state CARB legal and give you horsepower upgrades. We suggest that you contact the dealer you purchased your vehicle from to address any warranty questions.

A few years ago I purchased a 408 cid Mopar crate engine for my mint ‘89 Dodge Diplomat. I’m looking to upgrade the intake manifold. How many 4-barrel intakes does Mopar offer for this engine and which one do you recommend? No modifications have been made to the engine and the car is used on the street.

MM: The 408 is a great small block stroker. We recommend using the manifold that comes on the engine from Mopar, which is an M1 single-plane intake (P5007380AB). If you run into a situation where this intake is too tall and there are hood clearance issues, you can use the dual-plane intake (P5007381AB – above). We made the most power with the M1 single-plane intake during our dyno testing sessions.

I am looking to drop a 1993 Magnum® 5.9L in my 1973 Dodge W200 Power Wagon equipped with a TorqueFlite 727 transmission. Other than modifying the bell housing for the sensor, will everything bolt up correctly? Is there any sort of balance issues I need to worry about?

MM: The Magnum engine will bolt right up to the 727 with no issues. If you have a neutral balance converter you can purchase the Mopar weight package (P5249843 – shown above) and weld the balance weights to the converter. As an alternative way to obtain the correct engine balance you can purchase the Mopar flex plate P4876706 for a symmetrical converter lug pattern, or 53008669 for an offset lug pattern.

I am happy to see Mopar is once again producing the HEMI Gen II dual-quad street intake manifold. Are there plans to reproduce the air cleaner as well? Not many non-original air cleaners will fit under the hood.

MM: Mopar Performance used to reproduce the “Chrome Dome” air cleaner assembly under the part number 77R06313 but it was discontinued October 2010. You can still purchase this style air cleaner assembly from an aftermarket manufacturer.

I have a recently rebuilt 1967 318 block (bored .040 over) in my daily-driver ’68 Plymouth Satellite and I’m looking to upgrade the cylinder heads and intake manifold. What cylinder heads and 4-barrel intakes are available from Mopar for my ’67 block?

MM: We have many different heads and intake manifolds but we would need more information on your engine combination, i.e. compression ratio, camshaft profile etc. Feel free to give us a call (888) 528-HEMI and we can help you select a good combo for your car.

Does Mopar have a cold air intake for a 2000 Dodge Dakota with 5.9L V-8?

MM: Yes, Mopar Cold Air Intake, Part No. 77060008AB.