IS300 Fuel Pump Mod

The Stock IS300 and Altezza fuel pump has a variable voltage control unit that works well with stock set ups, but not so good when you plan to make more power. The stepped voltage can cause heat both in the pump and in the wire and connections as well as low fuel flow when you’re trying to run a fuel system harder then it’s designed for.

The XM fuel pump mod is a full power system that allows fuel pumps to run at their highest capacity without being starved for voltage!

Power Capicity

This is the most important part to understand! The factory contact pins on the pump hanger and our plug in assembly will only safely handle 10 Amps. Most aftermarket fuel pumps operate at a 12 Amp minimum and then rise with boost. We have found the only reliable pump that supports 550 HP and fits the amperage requirements is the Walbro 255HP. We have not found any pumps with similar or greater output that fit within the amperage supply limits of the stock hanger.

Installation

Installation is straight forward, pull the bottom half of the back seat, open the fuel pump access panel and unplug the pump, then plug in the new XM unit to the pump base and plug the factory chassis plug into the new XM unit. Then you need to run the heavy gage main positive cable to the battery and the new heavy gage ground wire to the gold zinc plated bolt that holds the seat back. Do NOT use one of the painted bolts that are also under the seat, they will not conduct power! Be sure to protect the wires where they pass through any panels or have pinch or chafe points!!

Stock ECU's

This system does not run with the factory ECU unless you bypass the variable voltage unit. While bypassing the voltage unit will send full power to the fuel pump, it's still through wire that is too small for higher output pumps and can cause heat both in the pump and the wires and terminals, yes this can cause a melt down of the wires or terminals/plugs, yes we've seen it happen.

2 Types

We offer two types of XM pump mods, the Series 1 has 14' of main power cable to reach the front of the car for use with the stock battery location. The Series 2 has 7' of power cable for use with trunk mounted batteries.