GB: Full Function Engineering Crank Trigger Kits - S4, S5, and RE 13B's
Rotary Freak
Joined: Oct 2001
Posts: 1,568
Likes: 2
From: N.J. USA
I have a question for you. on the high boosted rotaries (40 to 55lbs of boost) the eccentric shaft has a tendency to flex. will this flexing cause the trigger wheel to go blind? meaning, miss the signal from the sensor? how far could the trigger wheel move away(up down side to side) from the sensor and still send the timing signal? very critical for high hp rotaries.
I have a question for you. on the high boosted rotaries (40 to 55lbs of boost) the eccentric shaft has a tendency to flex. will this flexing cause the trigger wheel to go blind? meaning, miss the signal from the sensor? how far could the trigger wheel move away(up down side to side) from the sensor and still send the timing signal? very critical for high hp rotaries.
The angle is very very small in the worst case situations and in those instances you'll be replacing rotors, bearings, housing, etc first.
Just to put some numbers to it:
Lets say you have a high RPM motor (8500+) and use 0.004" clearance on your front stat bearing.
If the E shaft goes through the oil and contacts the bearing at the farthest two corners it will only see an angle of 0.126*
At the trigger wheel this equates to 0.0088" runout.
This is within the normal allowable limit for most VR sensors. (this depends on wheels size also)
If there is a serious concern we offer a Hall sensor setup as an upgrade too.
On a side note FD's are read from behind the wheel so will be affected none from crank flex.
Rotary Freak
Joined: Oct 2001
Posts: 1,568
Likes: 2
From: N.J. USA
To simplify it, No.
The angle is very very small in the worst case situations and in those instances you'll be replacing rotors, bearings, housing, etc first.
Just to put some numbers to it:
Lets say you have a high RPM motor (8500+) and use 0.004" clearance on your front stat bearing.
If the E shaft goes through the oil and contacts the bearing at the farthest two corners it will only see an angle of 0.126*
At the trigger wheel this equates to 0.0088" runout.
This is within the normal allowable limit for most VR sensors. (this depends on wheels size also)
If there is a serious concern we offer a Hall sensor setup as an upgrade too.
On a side note FD's are read from behind the wheel so will be affected none from crank flex.
The angle is very very small in the worst case situations and in those instances you'll be replacing rotors, bearings, housing, etc first.
Just to put some numbers to it:
Lets say you have a high RPM motor (8500+) and use 0.004" clearance on your front stat bearing.
If the E shaft goes through the oil and contacts the bearing at the farthest two corners it will only see an angle of 0.126*
At the trigger wheel this equates to 0.0088" runout.
This is within the normal allowable limit for most VR sensors. (this depends on wheels size also)
If there is a serious concern we offer a Hall sensor setup as an upgrade too.
On a side note FD's are read from behind the wheel so will be affected none from crank flex.
Full Member
Joined: Nov 2010
Posts: 181
Likes: 0
From: York, PA
Specialized Kits
I have spoken to you before and was wondering if you would be able to make a special center section that mounts to the crank pulley. See I was thinking about eventually upgrading to a dry sump oil system and seeing if you would be able to make a center section that would include a 1" drive mandrel which could be used to mount a gilmer drive and spin a dry sump system, or like Beefcake used the custom mandrel he had made in post #187 a mechanical fuel pump. One advantage I can see of using a 1" mandrel rather than a perminently mounted gilmer drive gear like Beefcake's is that you can interchange gears and fine tune the pump speed to adjust flow rates.
I have drawn up a model in solidworks to give you guys an idea of what I am talking about doing
I have drawn up a model in solidworks to give you guys an idea of what I am talking about doing
I was looking for an alternative for the crank pickup for my race car 20b build and came across this thread, Very nice work, I love it. I will PM you on what options may be available for my build but looks like it should fit what you have going already since I am going to be moving to a motec m84 ecu, possibly gilmer pulleys, and 20b dry sump cover.
I was looking for an alternative for the crank pickup for my race car 20b build and came across this thread, Very nice work, I love it. I will PM you on what options may be available for my build but looks like it should fit what you have going already since I am going to be moving to a motec m84 ecu, possibly gilmer pulleys, and 20b dry sump cover.
We've been talking about the dry sump stuff for a while. Sent you a PM.
Thanks
trying to download the crank trigger wiring diagram from your site but i dont have microsoft excel. i got the crank trigger kit with the 2 wire mag sensor and i know i have to use the yellow and green but from which harness.... the J4 trigger input or the J5 Home input? anyway u can post it on here?