In the early 70’s when the original PHD (Mantech, which became Magnaloy in 1997) manifolds were designed, the orientation of the pressure (P) and tank (T) passages through the manifold were located without a lot of consideration for the cartridge relief valves which would be mounted on these manifolds. The most common cartridge relief valve relieves pressure from the nose port to the side port. Therefore, the nose port needs to align with the P passage of the manifold and the side port with the T passage. In the Old Style PHD D03 Manifolds the P passage was located nearest the back of the manifold. When machining the relief cavity, the cartridge side port aligned with the P passage in the manifold. This required the cartridge relief valve to operate in a reverse orientation or flow from side port to nose port.

PHD subsequently redesigned the D03 Manifold to allow greater flows and corrected this situation. On the New Style D03 Manifolds the body dimensions were increased from 2 3/4 inch square to 2 3/4 inch by 3 inch and the T port was located nearest the back of the manifold. The valve pattern was off-set towards the “A” & “B” surface, the P & T passages were increased from .562 inch to .650 inch and the P & T port size was increased form #8 SAE to #10 SAE for the SAE thread option. the NPT port size did not change.

The Old Style PHD D03 Manifold had a part number scheme of 1-(Material Code)(D03 Code)(Thread Code)(Valve Spacing Code)-(# of Stations)(Option Code, if required). Example: 1-1122-02 or 1-1122-22 (with relief cavity). With the redesign, two additional digits were made available for options and a “-0” was added to the end to designate the design series, example: 1-1122-0200-0 or 1-1122-0202-0 (with relief cavity). Later, due to confusion between the two part number scheme similarities, the Old Style was renumbered with a “Special Manifold” designation of “SM-9” and the first dash was dropped from the number. Therefore, 1-1122-02 became SM-911122-02 and 1-1122-022 became SM-911122-022.

When Magnaloy purchased the PHD (Mantech) manifold division, we developed our own numbering scheme and the Old Style D03 is now SBM-(Material Code)SP03(Thread Code)(Valve Spacing Code)-(# of Stations)-0/(Option Codes). So the 1-1122-02 became SM-911122-02 and is now SBM-ASP03S2-02-0/Z and 1-1122-022 became SM-911122-022 and is now SBM-ASP03S2-02-0/C. When ordering an Old Style PHD D03 Manifold from the original numbering scheme it is imperative not to confuse this part number with PHD redesigned D03 part numbering scheme with the “-0” on the end. These are not interchangeable parts for retro-fit purposes.