Oil & Coolant Mods

Water Jacket Modification

There are a few different methods which REC offers to help improve the flow of coolant in the engine water jacket area. Rotor housing "ribbing" and removing additional material around the leading sparkplug area are two of the common modifications. We can also match port the existing galleries so there is no overlap which also improves flow. We perform different technics for different applications.

Price range: $130-$340 per engine

Please inquire for more information and details on pricing.


Oil Passage Matching

This process is designed to correct misalignment of factory oil galleries located in the castings to other subcomponents. REC recommends this modification for all high performance street and race applications. Some of the techniques require us to first enlarge the galleries, and then blend the gallery outlets to the feed side of the subcomponents.


There are three main locations which are equal parts in the "oil passage matching" upgrade that RE offers.

Stationary Gear Matching

This is where the main internal oil feed passages within the and housings are in some case enlarged first, and in all cases match to the stationary gear passages using a machining process. The area is then polished after matching for optimum flow.

Oil Pump Matching

This is where the oil pump flange is machined out to provide extra flow and properly match the discharge area of the oil pump. It is recommended for all performance engines to have the discharge passage from the oil pump bored to a larger diameter. The oil pump gallery area of the front plate is actually a very restricted area for proper oil flow and has bad alignment characteristics. This area is then polished after machining for optimum flow.

Oil Filter Pedestal Matching

Last but not least, REC always recommends to properly match and align the rear housing pedestal to oil filter adapter. Again, it is recommended to enlarge these passages first, and then check and correct the alignment with the actual subcomponent which the engine will use. In some cases corrections will need to be made to the aluminum pedestal itself. We have seen dramatic differences in the location of the factory galleries comparing the one housing to another. This area is then polished after matching for optimum flow.

Cost for all 3 as a package: $290.00


Coolant Seal Grooving

It is sometimes necessary to use 1986 up rotor housings with early type end housings or vice/versa. The issue becomes the lack of coolant seal grooves in either the rotor housing or the end housing. REC offers a CNC process to cut both the outer and inner seal groove into the corresponding housings. We choose to use the program to cut the 1986 up depth and width so all years of engine housings will be upgraded to the heavier and readily available O-rings. The charge is for each surface (1 inner and 1 outer groove)