can you explain at the bad things to me about the Optispark in our cars i have had mine replace be4 payed like 900 for a full tune up be4 i knew of all i know now i just want to no the flaws in it and if theres different one to get like whats that vented one i hear about on here , please just teach me a little about thanks

 

your not getting a response because the OPTI is a constant issue, just do a search on OPTI and start reading, it's mostly a problem with design, the GM OPTI has an oustanding high speed bearing but crappy housing to hold it in, it also has the notorious moisture issues that cause many problems. You'll find a ton of stuff on here.

 

Your 95 already has the "vented" OptiSpark. A new one will cost you about $195 from the discount GM parts dealers that are recommended often on this board. If you are patient, you can replace it yourself. But it can be a bit of a challenge for someone who doesn't work on their car a lot already. Can be done though, and you will save a ton of money.

There is only one available direct replacement... a billet case unit (I think its called Dynaspark or something like that), with upgraded parts for about $600. A little pricey. There are rebuilt units and 1/2-units (cap & rotor; optical section) available from the chain auto parts stores, but the experiences I've seen posted here tell me that you should stay away from them, and use ONLY genuine GM full replacement.

The Opti is the perfect ignition when it works... as soon as it starts to go bad, it can cause all kinds of problems. Typical problems are rough idle, stumble accelratring off idle, surging/flat spots up to about 2,000rpm, and misfires (on and off) from 4,500rpm to redline. Can cause excessive knock retard.

I would disagree that it had a great bearing already... mine could barely be turned at 50K miles. Many people have found this to be the case. Appears the seal on the 4-pin wiring harness connector deteriorates, and that's how coolant from the weep hole on the water pump gets into the case. The bearing retainer starts to rust (also caused by ozone produced by high voltage spark discharge at the cap/rotor), and the rust particles blind the optical sensor. The worn bearing causes wobble. The moisture causes carbon tracking and burned contacts in the cap/rotor section, just like it would in a conventional distributor.

Best thing to do is to get a full GM replacement, install it yourself, and make every effort to keep it dry.

 

DMX. if you talk to Phil at Dynaspark http://www.dynotech-eng.com/dynaspark.htm he can explain the bearing issue in better detail with you, I forget the bearing mgf company but it's the same bearing Dynaspark uses that's in the GM OPTI. Unfortunately Dynaspark has an inflated price for their handbuilt units, hence their high price. But there is no comparison to their unit vs the GM version. For example the cap/rotor housing screws are machined into not through the alum housing like the GM OPTI, thus preventing moisture passing through. They also put a lot of effort into sealing the unit better than GM in other areas. The optical portion of the GM unit is built my Mitsubishi and also used in the Dynaspark setup.

You'll get a lot of different opinions on here, some are based on their best guess and what they think vs facts so just read through them carefully.

good luck

 

thanks guys for answering me