How does anyone set the timing on an optispark?
Safety Car
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From: N.E. Ohio OH
Finalist 2020 C4 of the Year - Modified
You don't "set the timing". The optispark is located positionally via a pin in the end of the camshaft OR a keyed spline on the driving shaft. The engine knows where everything is via the sensor inside the optispark telling the ECM where it is positioned. If it is assembled correctly (and the timing chain, and other engine mechanical components), there is no need (for timing purposes) to bring to TDC on #1.
See if this link works for you. It shows the back of a late version Optispark
http://shbox.com/1/opti_back.jpg
this PDF shows an earlier version
http://aipelectronics.com/media/pdf/...tion_guide.pdf
See if this link works for you. It shows the back of a late version Optispark
http://shbox.com/1/opti_back.jpg
this PDF shows an earlier version
http://aipelectronics.com/media/pdf/...tion_guide.pdf
Last edited by drcook; Dec 7, 2019 at 10:15 AM.
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I'm replacing the timing chain and sprockets, new seals/gaskets etc, and plan on making sure everything goes back
in the correct orientation. So if I understand correctly, I just need to be careful that the drive gear for the optispark,
is installed in the same orientation as it was before removing it.
thx,
ed
in the correct orientation. So if I understand correctly, I just need to be careful that the drive gear for the optispark,
is installed in the same orientation as it was before removing it.
thx,
ed
Le Mans Master
Joined: Sep 2013
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From: near the thumb in the mitten
Actually the cap can stay on. Initially the Opti was service by replacement only, no reason to remove cap. Since the rotor is "keyed" to the cam there's no need to set rotor like in a conventional distributor. Spline type has gap with a missing spline. If positioned correctly, Opti will slide on with ltttle effort. If you have use force it probably out of position. The dowl type has a mark on drive that aligns with dowl. Opti should easily slide in place. You shouldn't need use boltd to draw Opti into.place.
Le Mans Master
Joined: May 2005
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From: Central Maryland
As others have noted, the drive shaft is splined, and keyed so as to only mate in the correct orientation. If it requires more than a gentle bump with your hand to mate the drive mechanism, it is not aligned correctly. Find the key and the mating keyway, and align them. It should slip on easily. As has also been noted by others, do NOT force it on by drawing it on with the bolts.
The opti sends camshaft position, velocity, and acceleration data to the ECM, which uses this data, along with input from multiple other sensors, to trigger the ignition coil at the correct time for a given set of circumstances. There's nothing for you to set. It's plug and play.
Live well,
SJW
The opti sends camshaft position, velocity, and acceleration data to the ECM, which uses this data, along with input from multiple other sensors, to trigger the ignition coil at the correct time for a given set of circumstances. There's nothing for you to set. It's plug and play.
Live well,
SJW
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I picked up the new timing chain and sprockets, and now I realize my question was misleading.
With the sprockets oriented correctly, top-to-bottom, 6:00 and 12:00, the opti can only be oriented with the keyed spline-drive in the 6 o’clock position. No guess work there!
That must mean that cyl 1 is at tdc at that point, and the opti (rotor) is at no. 1
Right?
With the sprockets oriented correctly, top-to-bottom, 6:00 and 12:00, the opti can only be oriented with the keyed spline-drive in the 6 o’clock position. No guess work there!
That must mean that cyl 1 is at tdc at that point, and the opti (rotor) is at no. 1
Right?
Le Mans Master
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From: near the thumb in the mitten
Yes, techinically it doesn't matter Opti is keyed to cam. It is suggested that pointer on balancer hub be at 12 o'clock when #1 is at TDC. So if timing marks are aligned bolt hub on crank. It's not supposed to matter since front half of LT1 is internally balanced. But per FSM in the off chance a vibration is present, repositioning balancer may help.
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Yes, techinically it doesn't matter Opti is keyed to cam. It is suggested that pointer on balancer hub be at 12 o'clock when #1 is at TDC. So if timing marks are aligned bolt hub on crank. It's not supposed to matter since front half of LT1 is internally balanced. But per FSM in the off chance a vibration is present, repositioning balancer may help.
Unfortunately, I didn’t matchmark it before it came off.
The damper is clearly marked with a triangle. But the crank-hub, is not.
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Someone on a different forum disagrees. So, the question still remains, how can an opti-sensor “self-correct” to fireing on #1, when it starts at or near #6?
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Thank you ihatebarkingdogs for the well crafted response!
That sure gives me and my friends something to kick-around while we hangout in the shop scratching our heads and drink a beer...
Very much appreciated
Ed
That sure gives me and my friends something to kick-around while we hangout in the shop scratching our heads and drink a beer...
Very much appreciated
Ed
Melting Slicks
Joined: May 2013
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From: Sacramento California
The rotor inside the optispark distributor has slots in a specific configuration and spacing to tell the computer exactly where the engine is in the rotation and firing order. As long as the timing set is aligned and the optispark is installed correctly on the front of the camshaft, there are no manual timing adjustments. It's all computer controlled using the inputs of the various engine sensors.
