Discussion
Some general advice on crank trigger:
- ensure that the toothwheel dont oscilate, tolerence <2/10mm
- Place the sensor as close to the trigger wheel as possible, 0,3-0,7mm
- be very caseful with the grounding, as ground loops, or ground noise can make very strange problems. Rule of thumb, ground the ecu to the engine block, on the upper part of the engine block as far away from teh alternator as possible. Make a common ground point on the cable from the engine to the ecu, aprox 10 cm from teh ecu. Connect all needed ground wires (for sensors, shields etc) in this point. Never ground a wire in both ends as this will make a ground loop (circular connection) that will introduce noise to the ground.
- The crank sensor will normally be ~180ohm if it's a VR sensor. Higher is better = stronger signal.
- Be sure to get the polarity right on the sensor, if the sensor is connected to a volt meter, and you put a piece of iron toward the sensor, shall it read a positive voltage. Removing the iron from the sensor shall give a negative voltage.
- After the sensor is mounted, and if you can get hold of an osciloscope, snap a picture. It shall give eg. 35 equal high pulses, and not a sine curve of the pulse hight.
And 9 of 10 issues with electronic ignition is related to bad trigger signal.
- ensure that the toothwheel dont oscilate, tolerence <2/10mm
- Place the sensor as close to the trigger wheel as possible, 0,3-0,7mm
- be very caseful with the grounding, as ground loops, or ground noise can make very strange problems. Rule of thumb, ground the ecu to the engine block, on the upper part of the engine block as far away from teh alternator as possible. Make a common ground point on the cable from the engine to the ecu, aprox 10 cm from teh ecu. Connect all needed ground wires (for sensors, shields etc) in this point. Never ground a wire in both ends as this will make a ground loop (circular connection) that will introduce noise to the ground.
- The crank sensor will normally be ~180ohm if it's a VR sensor. Higher is better = stronger signal.
- Be sure to get the polarity right on the sensor, if the sensor is connected to a volt meter, and you put a piece of iron toward the sensor, shall it read a positive voltage. Removing the iron from the sensor shall give a negative voltage.
- After the sensor is mounted, and if you can get hold of an osciloscope, snap a picture. It shall give eg. 35 equal high pulses, and not a sine curve of the pulse hight.
And 9 of 10 issues with electronic ignition is related to bad trigger signal.
The TR6 I did last summer, had the trigger wheel on the front pulley. I guess a flywheel solution is possible, by milling 35 slots into the back face of the flywheel, but will be a lot of work. And precision will be equal in the 2 cases, as oscilation of the crank speed will be in a 120deg phase, so timing offset will be equal on each 3 cyl/rotation
Seems like the balancer is to close to the casing for the trigger wheel to mount directly. So in case it shall be on the back side of the pulley, do the pully need maschining. Removing weight from the balancer is not the best solution, but as it will be replaced with the weight from the trigger wheel can it be ok. But the plug'n play solutiion seems to be a "front of pully" removing a bit of the fan spacer.
Flywheel solution
http://www.groups.tr-register.co.uk/cotswold-vale/...
Front mounted
http://www.teglerizer.com/fi/cranktrigger/ms_gt6_c...
http://3.bp.blogspot.com/-jir18zPD6uc/ToDjpOPvtXI/...
Rear mounted
http://photos1.blogger.com/blogger/7831/805/400/cr...
Flywheel solution
http://www.groups.tr-register.co.uk/cotswold-vale/...
Front mounted
http://www.teglerizer.com/fi/cranktrigger/ms_gt6_c...
http://3.bp.blogspot.com/-jir18zPD6uc/ToDjpOPvtXI/...
Rear mounted
http://photos1.blogger.com/blogger/7831/805/400/cr...
Long cranks twist a fair bit. Six cylinder engines have long crankshafts. The flywheel exerts a dampening effect, on all of that speeding up, and slowing down, that the front of the crank sees. The flywheel is the most stable location from which to trigger the ignition. If you want simple, mount the trigger wheel to the crank snout. Another option is to utilize the distributor drive.
Best regards,
Bernard.
Best regards,
Bernard.
That's how it's done in man yengines, my S type have a 36-1 triggerwheel on the crank next to the cam drive. Another option is to do like the P38 thor version of the rover V8. It have a axial mounted sensor in the timing cover, and use a slottet camsprocket as trigger wheel.
We have done quite some experiments with an optical distributor pickup from a nissan, a bit like the system in an oldschool ball computer mouse. Working ok for ignition, but the cam sync mode (to get a 720 cycle for ignition and injection) did'nt work out.
And yes, the belt pulley/damper do oscilate more that the flywheel, but for ignition purposes will it be rather irrelevant, as the period between ignition events and pulses are equal at 120deg.
As you can see from this trigger log from my engine, do the period time between trigger theeth's vary in slight sine curve. Of cause do the wissing thooth make one period time double against the other ones. In case of a straight 6 engine
First a triggerlog from a 4 cyl engine under cranking (the sine curve is very visible at comression slow's the crank rotation speed), and second picture from my V6 under idle conditions.
3'th picture, a screen shot measuring the time diffrence between ignition events, in case one cylinder is misfiring wil it clearly show that the rotaion speed of the crank is lower after the missing fire.
We have done quite some experiments with an optical distributor pickup from a nissan, a bit like the system in an oldschool ball computer mouse. Working ok for ignition, but the cam sync mode (to get a 720 cycle for ignition and injection) did'nt work out.
And yes, the belt pulley/damper do oscilate more that the flywheel, but for ignition purposes will it be rather irrelevant, as the period between ignition events and pulses are equal at 120deg.
As you can see from this trigger log from my engine, do the period time between trigger theeth's vary in slight sine curve. Of cause do the wissing thooth make one period time double against the other ones. In case of a straight 6 engine
First a triggerlog from a 4 cyl engine under cranking (the sine curve is very visible at comression slow's the crank rotation speed), and second picture from my V6 under idle conditions.
3'th picture, a screen shot measuring the time diffrence between ignition events, in case one cylinder is misfiring wil it clearly show that the rotaion speed of the crank is lower after the missing fire.
http://trigger-wheels.com/store/contents/en-uk/d46...
Getting this kit and getting someone who has fitted a few to do it for me.
Any objections or ideas welcome. Will be a week ish before I order.
Regards,
Stevo.
Getting this kit and getting someone who has fitted a few to do it for me.
Any objections or ideas welcome. Will be a week ish before I order.
Regards,
Stevo.
Have you looked into a Nodiz system??
http://www.nodiz.co.uk/nodizpro-features.html
N.
http://www.nodiz.co.uk/nodizpro-features.html
N.
Edited by Dollyman1850 on Saturday 7th March 17:54
Dollyman1850 said:
Have you looked into a Nodiz system??
http://www.nodiz.co.uk/nodizpro-features.html
N.
No, has anyone else for a 2500 engine?http://www.nodiz.co.uk/nodizpro-features.html
N.
Edited by Dollyman1850 on Saturday 7th March 17:54
Thanks for the link.....
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