Thread: General Hemi Info Part 2

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Intakes: Intake manifolds for the 331-354-392 HEMIs are available in just about any configuration you could want. As far as the intakes for these engines they all physically fit even though the 392 is a tall deck motor. Instead of making the manifold wider to fit the tall deck and keeping the heads at the same physical dimensions Chrysler made the heads wider. (I’m not sure, but I believe in the case of the Dodge and Desoto tall deck motors the intake was wider).

If you don’t mind or even desire to run just a single 4 bbl on your HEMI, don’t discard the factory intake out of hand. As far as I know there was a single 4 bbl manifold available for every early HEMI (even though a lot were produced with a 2 bbl). These manifolds are generally a good dual plane design and can produce respectable results. To run a latter style carb on them will require the use of an adaptor plate, and for best results the ports should be matched/blended to the throttle plate throats.

Many of the early HEMIs also were available with a factory dual quad set-up. I personally am not very impressed with them. IMO they were a pretty poorly designed single plane unit and while they do have a marked improvement on top end power the part throttle response leave a lot to be desired. Personally I would look for a more modern intake if you have your heart set on a dual quad set-up.

LOTS of CARBS and MECHANICAL INJECTION: Many of the induction systems produced in the late 50’s and through the 60s for the early HEMIs were designed strictly for drag racing. They only had to idle and have part throttle response enough to get to the starting line. They can be made to work on the street, but a lot of playing and fine tuning will be required. Just something to keep in mind when looking at them.

Shown below is on the left an early wet style intake (note the thermostat housing built into the intake) and a latter dry style 2 bbl intake.