Many engines from the 1990s onward already have the sensors needed to support sequential fuel injection. But what if you’re converting an older carbureted engine to EFI, or working with an early bank-to-bank EFI system? Sometimes you can source bolt-on solutions from later engines or aftermarket kits. But when bolt-on parts aren’t available—or simply not in the budget—you can fabricate your own crankshaft and camshaft position sensor setup with basic tools.
In this example, we installed a 36-1 crank trigger wheel and a camshaft position sensor on a Chrysler Slant Six using just a MIG welder, hacksaw, and hand drill.
Crankshaft Position Sensor Setup
Mounting the Trigger Wheel
The first step is adding a trigger wheel to the crank pulley. We offer universal 36-1 trigger wheels, and in this case the Slant Six conveniently shares its crank trigger bolt pattern with a small-block Chevy. That means you can use off-the-shelf 36-1 or 60-2 wheels designed for the Chevy pattern, or adapt one of our universal wheels with minor drilling.
Building the Sensor Bracket
Next, you’ll need a sturdy bracket for the crankshaft position sensor. On the Slant Six, the timing cover provided the best option—flat, strong, and easy to weld. We welded a short piece of 1" square steel tubing to the timing cover, then drilled a hole for our 12mm threaded Hall effect sensor.
Be sure the bracket is rigid to avoid vibration, and confirm the sensor gap after installation.
Camshaft Position Sensor Setup
The camshaft position sensor can be trickier, since most cams don’t extend to the front of the block. Fortunately, the Slant Six uses a mechanical fuel pump eccentric that comes very close to the fuel pump mounting flange. This made it possible to adapt a simple solution:
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Start with a Moroso fuel pump block-off plate.
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Drill two holes for our tabbed-mount Hall effect sensor.
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Seal it in place with RTV.
Inside the crankcase, the sensor lines up perfectly with the fuel pump eccentric to provide a cam sync signal. Testing with a multimeter confirmed proper operation: 12V with the lobe far away, and switching to ground as the lobe passes.
Because the 36-1 crank trigger handles precise timing, the cam sensor only needs to identify engine phase—it doesn’t require pinpoint accuracy.
Other Options for Cam Sensors
Not every engine has a convenient fuel pump eccentric. Here are two proven alternatives:
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Distributor conversion: Modify a distributor by cutting it down to a single tooth, turning it into a reliable cam position sensor.
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Cam sprocket modification: Weld or press a stud/bolt into the cam sprocket and fabricate a sensor mount on the timing cover.
Tools and Skills Needed
You don’t need a full machine shop to add sequential injection capability. A MIG welder, hacksaw, drill, and some creativity will get the job done. With careful fabrication, you can retrofit reliable crank and cam sensors to almost any older engine, opening the door to the precision and efficiency of sequential fuel injection.