DIYautotune's CAS replacement wheel
#21
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The MS2 might be able to handle it, but with a 360 tooth wheel, the poor little MS1 would probably crash. At high RPMs, I doubt it would even be able to handle the primary interrupts fast enough, much less actually run the engine. For comparison, an engine with a 360t wheel running at 7,000 RPM would put as much interrupt workload on the CPU as an engine with a EDIS-style wheel (36-1) running at 72,000 RPM.
The TEC lineup as one of the most accurate ignition systems available and it only uses 60 teeth, tell me why more would help?
#23
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Nissan used dedicated hardware to handle the 360 slit ring. Neither the MS1 nor the MS2 can really use that set of slits properly unless someone tried to clone the external counter circuit Nissan used and write code to make it work.
The MS3 is a different case - it's possible to program the X-gate to take the place of the stuff Nissan used to run this wheel.
The MS3 is a different case - it's possible to program the X-gate to take the place of the stuff Nissan used to run this wheel.
#24
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Maybe if you held RPM steady. With rapidly changing RPM, the higher tooth count wheel would be better (assuming (1)your processor is up to the task. so far, the MS3 is doing well with 360 tooth testing; (2) you don't have an abnormal level of slop in your timing gear).
#25
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Any slop in the cam belt system as a whole (which I measured at nearly +/-5° steady-state in my engine with a new timing belt) will remain unaffected. Ergo, periods of low delta-RPM and high load (eg: boost in 4th or 5th gear) will suffer from equivalent scatter regardless of toothcount.
#32
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It maybe the material as well, I didn't check if it was metal or alu but if a tad thicker wheel keeps it from bending like it does I would suggest diy to go for it if costs don't go up drasticly as well if it can still be laser cut.
#36
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1.6 93=< do drive the tach of the coils but having a different cam\crank setup has no bearing on the output of tach signal.
And if you do convert to seq spark you would have to get tach input from a different source as you would change out your coils as well more than likely.
on the 1.8s I don't know wheres its driven from.
and yes cut off one if you want the TSE 12 tooth to be a 12-1
Besides that if you are going to convert to this new wheel I take it you are running a standalone so you might want to consult with the manual and see if it can output a tach signal
And if you do convert to seq spark you would have to get tach input from a different source as you would change out your coils as well more than likely.
on the 1.8s I don't know wheres its driven from.
and yes cut off one if you want the TSE 12 tooth to be a 12-1
Besides that if you are going to convert to this new wheel I take it you are running a standalone so you might want to consult with the manual and see if it can output a tach signal
#38
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Anyways going back to the thread I used first 345 tigger offset to get my engine to fire up. No go just loud back fires. Read up something so I started advancing timing got to 200 where it fired and ran like a weed wacker. Finally end up at 135 trigger offset with 18 degrees of timing at idle.
#39
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Just once, but apparently I didn't put two and two together.
I don't understand why. Why am I required to run a 12-1 CKP if I have a single-tooth CMP? It seems logical to me that I can use a single tooth CMP to indicate position.
Why not run the 12-tooth wheel for less scatter?
Got it.
Thanks.
Why not run the 12-tooth wheel for less scatter?
Thanks.
Last edited by hustler; 01-10-2012 at 04:11 PM.