Wideband AFR readings on RV8 3.9
Discussion
I've just installed a wideband AFR meter made by NGK sparkplugs, who make the sensor, so it should be fairly accurate. The car is a 1987 TVR 390SE with 3.9 Rover V8 modified by NCK.
With fuel pressure at 2.50 bar the car idles at 12.5 AFR! cruising at 40mph its about 14.3 to 14.8 and under full load acceleration 6,000 rpm gets you about 15 - which seems dangerously lean to me. (fuel pressure also checked out ok at this load). Also when you come off throttle, the car occassionally dies, or at least goes to a very low RPM.
Can anyone tell me if I'm right in thinking the Idle/cruise should be close to 14.7 and under full load close to 12.5 ?
Oh, it has a flapper injection system with lucas 4cu.
-Jim
With fuel pressure at 2.50 bar the car idles at 12.5 AFR! cruising at 40mph its about 14.3 to 14.8 and under full load acceleration 6,000 rpm gets you about 15 - which seems dangerously lean to me. (fuel pressure also checked out ok at this load). Also when you come off throttle, the car occassionally dies, or at least goes to a very low RPM.
Can anyone tell me if I'm right in thinking the Idle/cruise should be close to 14.7 and under full load close to 12.5 ?
Oh, it has a flapper injection system with lucas 4cu.
-Jim
The Lambda sensor is in the left hand side down pipe, about 6 inches upstream of the O joint to the centre box everything appears gas tight, so no air should be being sucked into the exhaust.
The AFM and ECU look to be modified by NCK , and bear the NCK number on them, however, the engine has been rebuilt subsequntly. The air bypass is turned all the way out, so I am thinking the flapper needs a bit of TLC.
The AFM and ECU look to be modified by NCK , and bear the NCK number on them, however, the engine has been rebuilt subsequntly. The air bypass is turned all the way out, so I am thinking the flapper needs a bit of TLC.
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