TR6 Sequential Injection
As part of the fuel injection conversion final tuning stage, the plan is to move from phased batch injector firing to sequential firing. In phased batch two injectors are fired at the same time. On the TR6 number one and number six fire simaltanoeusly so one of those fires toward the back of a closed valve. Sequential injection fires individual injectors as the intake valve opens. Surprisingly those in the know say there is little to be gained by upgrading to sequential injection other than the ability to trim individual cylinders. With number six cylinder running a bit rich I’ll soon be able to lean it out a tad.
Electromotive’s TEC3 system has the ability to switch to sequential injection by changing a couple of menu options and some injector wiring. The only additional hardware required is a camshaft position sensor to announce when number one cylinder is approaching top dead center. The timing cover was my first thought. Add a tooth to the face of the cam gear and poke a magnetic pick up through the chain cover. This can be done but it is wouldn’t be as clean an installation as I’d like and could be destroyed if the fan belt broke. It dawned on me that the distributor was still in place to drive the oil pump and mechanical tach. Although the computer puts out a tach signal for an electronic tach, I wanted to stay with the original instrumentation. I had planned to cut the distributor down to just a stump as a tach drive so why not add the cam sensor to the same stalk?.
A junk distributor has been dissasembled, (everything was stuck keeping it from adavancing), and cut down on a lathe. The housing was cut way down eliminating all of the upper bell and electrical components. I used heat on a stuck screw and damaged the nylon tach drive gear. Duh! What’s left is a pretty short stub. The main shaft was cut off just above the upper bushing and a piece of 3/16″ square stock welded on as a tooth for the magnetic pick up to sense. You can see the tooth facing left at the very top of the photo. The distributor turns at camshaft speed so it should work perfectly. Still to done is to make an aluminum cap to hold the sensor and prevent oil leaks.
I’m hoping to get the car back from storage on April 10, 2004. And then there’s that supercharger. . . . .