C20XE Trigger Wheel query

[keybaud]

The C20XE has an internal 60-2 trigger wheel, which I've been told can cause problems if the engine revs higher than a standard one, and it was recommended that I fit an external 36-1 to overcome this problem.

 

I assume that this is a limittaion with the sensor and not the ECU's ability to process the higher data rate, but I can't find any technical discussions about this online. Can anyone let me know if this is true or not, etc.

[Lee Fowler]

Have you looked on the SBD website?

 

Lee

[Harry Flatters]

I run a standard trigger wheel and crank sensor to 8750 on a 265bhp VX with absolutely no problems.

[Bob Simon]

I assume that this is a limittaion with the sensor and not the ECU's ability to process the higher data rate

 

No. The issue is the internal trigger wheel hand grenading at high RPM. Lots of nasty chunks loose themselves within the crankcase.

 

Just adding an external wheel won't cure the problem unless you do a complete tear down and remove the internal wheel.

 

There's a thread with photos somewhere here on BC.

[EFA]

I used the standard sensor (albeit on the back of the flywheel) to 9750rpm. No issues.

 

 

[michaelw]

I have a 190 bhp VX but only rev it to 7000 or just over and had a trigger wheel crack. It caused a rev-limit type missfire above 5000. So I had to get the engine out to replace it and did consider going for an external sensor. As others have said I wasn't happy to leave the cracked one in the engine in case it broke up and figured others don't have problems and as the engine had to come out I just replaced with a standard wheel.

 

Not sure whether this helps other than to say they do fail.

 

 

 

 

Michael.

[Paul Deslandes]

This is the earlier thread where a trigger wheel had grenaded. If you want to go to an external sensor you'll need a means of mounting it adjacent to the teeth. The SBD version uses a machined lug which is part of their dry sump casting. Whatever you do it needs to be absolutely rigid to avoid noise on the trigger signal to the ECU. I replaced mine as I had the engine apart but you do have to have the crank out to remove the old wheel.

[ECR]

ISTR that the earliest trigger wheels were machined from solid and that it's the later pressed version that are slightly suspect. Having said that my VX runs sucessfuly on the pressed version to 8750 ...