Thread: General Hemi Info Part 5

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Short Block 4:

Oil Pans, Windage trays, and oil Pumps:

There are basically 2 types of stock oil pans for the early Hemi’s, a rear sump pan and a center sump unit. If your using a stock pan which one you choose will depend mainly on which one you have/which fits the car best (A center sump is REQUIRED if the engine is going into a 57-62 full-size MOPAR).

The use of a windage tray on a street engine is really a matter of personal preference and budget. Over the years many of the big 3 factory high performance engines came from the factory with them but an even bigger number didn’t. In the case of Chrysler’s early Hemi’s the factory installed a windage tray for the first few years and then dropped them. Personally I do believe they do some good at higher RPM and I am using them on both motors.


There are also 2 different styles of windage trays that can be used with these pans. The first is the 4 legged original early Hemi style. These were used on the early 331, but were dropped by 1955. The 4 necessary holes to mount these can be easily drilled into any of the early Hemi’s if you choose to run one on a Hemi that wasn’t originally equipped with one. Sitting on the engine they don’t look like they would be very effective, however once you look at how they sit in a stock rear sump pan you can see that they will be pretty effective.

The second style you could run with a stock pan is a modified Small Block MOPAR unit. These require the use of four special main cap bolts used to retain the tray, which has also been slightly modified by enlarging the mounting holes. This windage tray looks like it will work slightly better in the center sump pans.

One thing you might want to consider when deciding on whether you want to run a windage tray is the extra hassle they create if you ever have to remove the pan with the engine in the car. It’s one more thing that will have to be cleared if the pan has to come off and in some bodies this could be a real hassle.

Oil pumps: There are basically 3 types of oil pumps available that can be used in the early Chrysler Hemi. The type you use will depend in part on the type pan you choose to run.

The first is the stock type pump for the rear sump pan. It is necessary to use the correct original style pickup (either floating or fix depending on the pump style. I’m using the floating pickup on the 331.

The next style is the stock 392 pump which takes a threaded pickup and is necessary when using the stock 1957/8 passenger car pans.

At one point the supply of original style oil pumps appeared to be drying up (fortunately I had already bought my pumps before that happened). With the perceived need for replacement pumps due to the growing demand to build these old engines and design of some of the aftermarket pans, one company started building an adaptor to use a 340 high volume oil pump. Use of this pump and adaptor is largely a matter of choice partially dependent on the oil pan you are running. It should be noted that I have read in several places that the “high Volume” 340 pump only moves approximately 3% more oil than the stock 392 pump.


(One little side note on windage trays; around 68 or 69 when I was working in a Chrysler/Plymouth dealership I remember that Chrysler recommended running their factory Big Blocks that were NOT equipped with windage trays 1 quart low on oil at the drag strip. It was worth 1/10 second allowing non-windage tray cars to run a quickly as the windage tray equipped cars.)

Oil filter adaptors come in 4 basic flavors, the stock by pass style filter canister such as you likely got with the engine. An adaptor for a spin on filter (full flow) that positions the filter in the same position as stock (the filter sits upside down making for messy filter changes, but is some times required for clearance such as my 57 Plymouth). An adaptor that goes straight down, and finally a plate that allows you to run hoses and a remote filter setup.