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Norcalrv7 10-15-2017 09:11 AM

I made my own timing pointer off the front of my baffling, and bent it until it matched the TDC marks on back side of the ring gear. With the airplane chocked in the evening time, I was able to stand in the seat and see the marks pretty easily from the cockpit.

Mike S 10-15-2017 09:42 AM

Make a timing mark where it suits your needs
We set the engine-- not running-- to TDC using the starter pln setup, then created a timing mark on the flywheel where it was safest/easiest to see using masking tape and a Sharpie, then made up a pointer for that mark using a bit of safety wire held in place with tape.

There is a photo in the thread "My CPI installation" in this forum, a search will bring it up, if the following link doesnt work.

Toobuilder 10-15-2017 10:39 AM


Originally Posted by maus92 (Post 1211169)
I wasn't aware that Camaros or Mustang had props - I must have missed that class :) (We actually didn't have an auto shop at my high school.)

The suggestion about mounting the timing light similar to a prop balancer, then using a cell phone camera (I might use a GoPro) seems like a safer procedure.

Sorry, I didnt consider the prop because you dont need to have your eyeball exactly in plane with the ring carrier. If you are thinking your ear is a fraction of an inch ftom the prop,it does not need to be. Follow Mike S' example and place the pointer wherever its convenient on the case (preferbaly low and to the side), and you can keep your head well back from the prop arc. Use a piece of masking tape on the ring carier in the general location of the mark, a red sharpie for your mark, and a black one either side and it is very easy to see from 24 inches away (just the like the balancer on your Camaro or Mustang).

gasman 10-15-2017 10:49 AM

You might want to confirm the accuracy of your factory timing marks before you trust them.......

Or just purchase the pin..... and use your smart level or phone.

jump4way 10-15-2017 12:23 PM

A video showing how the timing light is used would be very informative to me also. I?m struggling to visualize the entire process.

Toobuilder 10-15-2017 09:58 PM

It's harder to explain than do. But you "move" the timing mark with the Magnet Position window key. Add one degree and if the timing mark moves closer then you are doing it right. You simply add or subtract until the mark aligns. The resulting magnet position is "your" permanent setting.

maus92 10-31-2017 08:40 PM

I was reading in the SDS CPI aviation supplement date 8/17:

"The CPI is not waterproof and will not function as designed if moisture invades the enclosure or power/ ground connections are interrupted."

Does this apply only to the controller box which is normally cockpit mounted, and no other components - like the coil pack?

"If you’re installing a single coil pack, remove the right magneto and any gears or bearings which rely on the magneto to hold them in place."

I intend on replacing the left magneto (and impulse coupling) and retaining the right magneto for the time being. Is this possible with SDS CPI systems?

I am so close to pulling the trigger...

rv6ejguy 10-31-2017 08:45 PM

Everything FF is waterproof.

You can remove either mag.

Be sure you have the larger 8 7/16 ID flywheel to be able to use our crank trigger hardware.

Toobuilder 11-01-2017 07:26 AM


Originally Posted by maus92 (Post 1215522)
....I intend on replacing the left magneto (and impulse coupling) and retaining the right magneto for the time being. Is this possible with SDS CPI systems?..

CPI/Mag combo's work just fine. Slight difference in LOP timing to compensate for the retarded timing of the magneto, but thats about it.

I will emphasize again that you buy the dual hall sensor on the first go, even if you dont think you are going to add a second system down the line. Its only a few extra bucks and makes it SIGNIFICANTLY easier to add a second system if you change your mind.

logansc 11-01-2017 07:42 AM

Guys: I am one of those like Tim2542 who initially wired my CPI such that I don't have a tach signal on my remaining magneto when I switch the CPI off during "mag" checks. Did I miss the instructions on that? I've been having way too much fun flying the airplane in its new, smoother, better starting life to stop now and work it out. However, as soon as winter arrives, I have a whole list of "stuff" to do and rewiring is one of them.

Is there a wiring diagram that I missed somewhere that will get renew the signal from my mag while still showing the CPI tach signal when I test them individually?


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