How to remove 20 teeth off a trigger wheel

[[email protected]]

I am needing to machine 20 teeth away from my 24 tooth 4age 20blacktop distributor trigger wheel. Andrew is my friend and he is a machinist. He is willing to put it in his mill and machine off the unwanted teeth.

A bit of back ground to the issue. The LinkG1 ver5 is set up with a daughter board that needs to see a 4 tooth pickup. The link ecu  I have  just purchased was on a 4agze turbo rally car. I have put it on a 4age 20v Blacktop.

Have a look at the picture attached and see I have marked with a red arrow the hall pick up that I am triggering the link ecu with.

Just say this picture was of my engine at TDC #1. 

Nnote: I have removed the trigger wheel with a puller and I can put it back on as I please as it is not splined and is an interference fit.

I also understand the rotor has to line up at Number one plug.

Question 1: What does the link G1 Trigger 1 ecu input want to see?

Question 2: Which teeth do I need to remove to get the link G1 to trigger correctly. Describe by colour.

Question 3: How does the link G1 work out where TDC is?

Question 4: When I press the trigger wheel back on with its four teeth shall I have it the tooth lined up right in the middle of the trigger or shall I have a bit of lead or lag? Just a little? Discribe in mm past or before.

Question 5: Can I use the advance adjustment in the software that I have seen to adjust after base timing is set with timing light? Explain the process a bit.

Thanks for all the shared knowledge.

[Adamw]

Doc attached, but basically it looks like you have it correct - keep the yellow teeth, remove the green ones.  Assuming the rotor is nicely centered under a post.

When you refit the distributor, line the center of the tooth up slightly before the pickup - this will be your cranking advance.  About where you have it in the above photo will be a decent starting point.

To set base timing, disable fuel system.  You then crank the engine with a timing light connected, move the CAS backwards or forwards so that the 10deg mark lines up.  Lock it up.

Then go into the software or hand controller and make sure the "base timing" number is set to 10deg also.

Modification for 24 tooth trigger wheels.pdf