The optispark on all B-bodies is vented. Stick with GM/AC Delco/Delphi.
Currently
199$ at summit. However I've been told that a GM rep on a conference call with Summit said they were not a GM performance part. Apparently, even though summit's site is displaying a " GM Performance Warranty" these are NOT AC Delco parts. Who knows.
I have a friend in Montreal with an AC Delco unit with under 200km. He installed a cam I sold him and put it on, then blew the engine. I sold him a complete stroker that had a brand new Delco unit so he no longer needs this one. I can put you in contact with him.
First and foremonst, ensure your opti is the culprit. It is very often misdiagnosed. One very common cause of misdiagnosis is the opti-coil wire. I've had more issues with leaky WP seals than the opti itself. Most damage occurs from the WP weeping into the opti or a failed vacuum harness. IOT replace the WP seal, make sure you get the appropriate tool. Either the actual Kent Moore or the replica from Buffman. It's pretty small, so if you need to borrow it, I'd be glad to mail it to you provided you mail it back. However you can buy it new from Buffman for about $11 shipped.
When I've had the opti out for various reasons, I've done the following as preventative maintenance:
1. use an E4 reverse torx socket to take it apart;
2. Apply red loctite to the 2 small screws holding the rotor in place ;
3. reseal the opti with a constant SMALL bead permatex #2 or equivalent;
4. replace the WP seal (as required). Felpro Timing cover gasket set TCS 45956 has all the gaskets you need. The 2 small o-ring are for the WP driveshaft, not the opti;
5. replace opti o-rings with 2x GM p/n 10474278 Distributor drive shaft seal (a new opti should have these already installed);
6. Clean the opti electrical harness contacts with contact cleaner, then shrinkwrap the connector on the opti side; and
7. Replace the opti vent harness. A failed/cracked vent harness will cause problems often misdiagnosed as the opti.
It's worth noting that the optispark is a very simple component and is easily serviceable. It contains the following parts:
1. the housing and trigger wheel;
2. the optical sensor; and
3. the cap and rotor.
Usually either the cap and rotor simply wear out or the optical sensor fails. Occasionally the trigger wheel rusts and gets coated with oil. Occasionally the two screws holding the rotor in place will get loose and/or back out. A few people have experienced failure of the bearing in there.
If you get trouble codes and the opti interior is clean, then the sensor failed. If you replace an opti because of a bad cap/rotor/secondary issue, save the optical sensor as it can be reused and is not cheap to buy on its own. Caps/rotors are wear items so just buy new ones.
You can watch this
http://www.impalassforum.com/vBulletin/showthread.php?t=255280]GM optispark service video to understand how it works in excruciating detail.
I keep a working coil and ignition control module (ICM) assembly in my storage compartment along with a cheapo ratchet and a deepwell socket for the coil studs. You can find a cheap one at a junkyard. 90% of opti failures leave you with a misfire but the car still runs. An ICM failures leave you stranded. Undo two bolts and three plugs and you can swap the coil/ICM assembly and keep going. When installing a new ICM
only, it's essential to ad the heatsink paste.
