For those of you that recently aquired an LT1 powered Camaro. One of the recurring problems is distributor failure. GM named this type of distributor Optispark, but the people that have to deal with it, refer to it as Opticrap.

The first version was unvented, and once moisture got in it remained there. The moisture would start corroding the distributor causing misfires and or crossfires, especially as the engine got hot, or under heavy load. The second version is vented with the hope that the engine would suck the moisture out. These work better as long as water is not poured on the distributor.

The other problem is the location of the distributor, which is under the water pump. As the water pump ages the seal around the shaft begins to leak and the coolant leaks on top of the distributor. The coolant seeps indide the distributor and totally messes it up.

The recommended fix by GM is to replace the distributor in its entirety. However; aftermarket distributor caps and rotors are available. Sometimes they solve the problems, other times they don't, as there is a bunch of electronics packed into the distributor.

This is a few of the websites you can go to and get more info on how to fix or uograde the distributor:

http://www.charm.net/~mchaney/optisprk/optisprk.htm Dissection of the Optispark
http://para.noid.org/~muttvette/opti.html How to swap the Optispark
http://www.dynotech-eng.com/dynaspark.htm Upgraded Optispark
http://www.houston-f-body.org/tech/optispark/ How to change the Optispark
http://z28.com/forum/showthread.php?t=36064 Optispark forum

Pete

 

Thanx for the info came in really handy! I recently bought a 93 and hopefully i don't have to replace that any time soon because the guy i bought it from said he just replaced the water pump,optispark,wires and radiator about a year and half ago.