4586

From reading all related opti-spark posts it appears that the ACDelco is the king of the road....but.......

Wondering if anyone has any good stories about optispark units out there?

Anyone get crazy mileage out of one or have a car with a long running life with an opti?

Fatdog2

I got 119,000 out of my original old 93 bird.It even survived a water pump fail.Still worked great when I traded it in.Now Delphi (who made them in the first place I think) still makes them with the Mitsubishi optical thing which is the best.When Mitsubishi sells them to Delphi the sale has to be for 100,000 units or more and that's why you won't find them in other opti's.I could be wrong(as I've been wrong twice so far this year,and the year is still early).Any way the Mitsubishi symbol is marked on the optical or cpu or something.GaryDoug and Injuneer can elaborate on this.Hope this helps.

timnfxr

Replaced my original factory opt in 2012 at 220k miles with a new Delphi unit. Now at 225k+ miles and still running great.

4586

Remember reading that the Mitsubishi sensor was the factor with the OEM opti's living so long.

I see that they sell "rebuilt" ACDELCO opti's (GM recommended rebuild) & wonder if they use the Mitsubishi sensor?

Injuneer

Always interesting to note that the "Opti" concept was the product of Diamond Star Motors.... a collaboration of Chrysler and Mitsubishi. They used it in the 3.0L V6 that was installed in Chrysler and Mitsubishi compacts in the late 1980's. They were wise enough to package it in the form of a "conventional" distributor, mounted on top of the engine, not under the water pump.

The concept and the sensor are excellent. The packaging proved to be a problem. If the whole thing was easy to access and maintain, I doubt that it would be considered a negative factor in the design and performance of the engine.

The improved spark and sequential injection timing accuracy helped the engine meet emissions through reduced spark scatter, and allowed a fairly aggressive spark timing. That resulted in power production that was very good for the time period.

The optical module has been shown to function reliably up to 8,000 RPM, in at least one LT1 build that I am very familiar with. Using an aftermarket system to move the high voltage out of the same housing seems to eliminate any problems related to the module. My unvented 94 started showing signs of stress at about 40,000 miles, the result of rust due to ozone. When we built the stroker 16 years ago, I bought an OEM "new in box" vented Opti from a member here for $200. Using only the optical module, feeding a MoTeC M48Pro ECU, is has supported an engine with a redline of 7,200-7,400 RPM. And a couple of missed shifts (back in the M6 days) that were data logged to reach 8,000 RPM.

Chimera96

My $.02 is the location of the Opti is the reason it suffers, as Fred notes. Beside being a PIA to service the LT1 water pump has its weep hole on the rear and pisses coolant right on the Opti

Other than a cap & rotor swap I am running the AC Delco the dealer put on back when my car was under warranty and they repeatedly replaced WP's & optis during the warranty period.

500 miles after my car went out of warranty I switched to a EWP. 90k miles later, same Opti but MSD C&R I put on when it had about 75k mi on the opti. and same EWP has 90k mi on it

Back when "thepartslady.com" was selling Delphi Optis for around $200 I bought one as a spare....still have it in my parts shelf.

4586

Next time I'm replacing a water pump may just install a tube in the weep hole and route a rubber drain hose around the opti?

I'll give you a 20% profit on your backup Delpi

Stephen68

i didn't have the cash to buy a new Delphi opti or MSD for my new motor build so i kind of Frankensteined one...i used the Mitsubishi reader from one of my Delphi units i found and bought a new MSD cap and rotor. during assembly and before installing the unit i sealed all places water could enter and added the hose and fitting to my weep hole. i also installed a shield i made from a piece of aluminum on my water pump to filter any possible leaks to the sides of the opti...so far so good....

Chimera96

doing anything to prevent WP leaking on Opti is a good idea.

No, my Delphi is not for sale. I am sure at some point my existing AC Delco will fail and the Delphi will replace it.