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Looking for guidance on connecting tach sense wire to optional 40 amp alternator available on the Jab 3300. As I understand it the tach sense wire is connected to the regulator output on the "stock" alternator setup. The 40 amp alternator has an internal regulator thus no separate regulator to hook to. May have to go with an optical sensor but trying to avoid that. Is anyone using the 40 amp alternator? Any suggestions?

I am not sure if this is relevant for your Jab engine. I have a 40A internal regulator alternator on my Camit 3300. The engine has a tacho sender that senses two magnets that are mounted on the flywheel. I would think the ignition on the jab is sensing magnets on the flywheel also. That would be a source for a signal for the tacho. The alternator does not have the pulse info needed for the tach.

Rick Caldwell
Xenos 0057

Rick, That may be the answer as I have the CAMit as well. Your thought is that I just attach the Dynon tach wire to that nipple. I guess I missed that on the installation manual (not the greatest manual in my humble opinion). Thanks. I will give it a try tomorrow.

Yes, I see no other way it could be done. You are ahead of me so let us know how this turns out.

I have the GRT Sport EX and remote engine monitor but still building the instrument panel, glare shield, firewall stuff.

My Camit is #088. Still in the crate stored in my house.

Rick Caldwell
Xenos 0057

I think I have mentioned this on a couple of other threads. The tacho on my 3300 Jab is driven by the low tension side of one of the ignition coils, the same wire that goes to the kill switch. It is a method suggested by the manual for the MGL RDAC and requires an external 10K series resistor. Has worked with complete reliability and accuracy for nearly 7 years.

Peter