This is one of my typical really long posts, so only read it if you're really bored.

So after owning the car for 14 years I finally had to do an optispark. I have replaced the unit before, back when I did all of my mods I converted to the new style, but I had never had to replace one on my car because it was bad. Some would say that for 7 years as a daily driver and some 70k miles this is a miracle, but I digress.

Anyway one day about a year ago I was driving the car and it just died for no apparent reason. I was able to drift it into a driveway and it eventually restarted. I blamed it on a potential slug of water from ethanol separation, it ran fine ever since.

About a month or so ago I got in the car and had a crank / no start condition. I pulled the plug wire and realized I was getting no spark. The coil wire and coil terminal didn't look like they were in great shape so I tried to clean them up as much as possible. I still got no spark, there were several possible reasons for this:

1. Bad MSD box
2. Bad Coil
3. Bad Ignition Module
4. Bad Opti
5. No signal from Opti

I first bypassed the MSD box and that didn't help. This didn't mean the MSD box was any good, but it did mean that if it was bad, it wasn't the only problem. I got out my old laptop so I could data log and see if I was getting an RPM signal while cranking. While playing with that I noticed that not only was I getting an RPM signal, suddenly I heard the coil arcing while I was cranking on it. Apparently it finally found a way through the corrosion. Leaving the MSD box bypassed I connected the plug wire and the car started right up. It seemed to run OK but it had a horrible misfire at 5500+ that it didn't have the last time I drove it.

This got me to thinking that maybe the coil / wire corrosion issue was the problem all along. Afterall the coil wire did look REALLY bad. I also thought that maybe the MSD box, with it's higher power spark, may have been masking the problem for a while until it finally corroded to the point where it couldn't fire.

All of my plug wires were MSD and looked in good shape except for the coil wire. I can't remember why but I had to replace it many years ago with a parts store junker. I decided the cheapest way to go would be to try a new coil wire. I bought a cheap set of coil wires. I cleaned up the terminal on the coil. It seemed a little better but still not great. I knew my plugs, although several years old, had less than 10k miles on them so they should be fine. At this point I was back to the optispark, but the high voltage side, not the logical side.

Although I wasn't particularly happy about this, I really can't complain. I saw what lots of miles with an MSD box did to my spark plugs, I knew the opti had just as many miles on it. Honestly it has taken a LOT of abuse, it's due. Afterall, aside from the optical pickup, it has a cap and rotor just like any other distributor. So I started pricing options.

First I contacted my friend who works at the dealership to see his cost. HOLY SHIT! His cost is now $400 with a $50 core. They used to be less than $300 with no core charge. This means that not only is the cost crazy high, even the "OEM" ones are now reman units with a 1 year warranty.

I didn't really like that option so I started looking at other options. I looked and most of the parts stores carry Cardone remans for about $130 with a lifetime warrant. I felt confident I didn't really need a whole unit so I looked at caps and rotors. The cap and rotor cost $140 with a 1 year warranty?!?!?

I also looked at the MSD pro-billet opti. I remember from years past that these had problems and were also $400+ so that wasn't the greatest choice. Looks like my only viable option was the parts store reman. I know in years past this was unthinkable, but my friend Brian had recently used one on his car and it worked just fine.

So, $130 for the opti, $50 for a core, a set of water pump gaskets, and 2 jugs of dexcool later I set about the project. With my friend's help we started last Saturday morning on the tedious task. I made it a point to pull the cap and rotor off the old opti to take a look and convinced myself that it was indeed badly worn and was very likely the root of my high RPM misfire.

Everything went as well as can be expected for such a tedious job and after about 6 hours we had it buttoned up. We were extra careful to triple check the plug wires on the opti because once it was put back together there would be no easy way to change them if we had one swapped. When I first went to start the car, it didn't really want to. It started to spin pretty quick but that first compression stroke stopped it dead. Odd, but the battery had taken some abuse and we did run it for quite a while using the electric water pump to purge the cooling system, so maybe it was weak. I tried a couple more times and eventually got it to fire. It seemed to idle a bit rough but I thought it might settle out, afterall it had been sitting for a while and my gas was pretty crappy, probably had phase separated as well.

My friend and I took off down the street and it was immediately apparent that something was obviously wrong. The car felt like it was missing like crazy and even the slightest load resulted in horrible pinging. This whole problem started with just a high RPM misfire so the problem was definitely worse. We had reconnected the MSD box, so we thought it might be possible that was the problem even though we knew it wasn't. I limped it to a gas station. I bought a bottle of HEET to help remove any water from separated ethanol and topped off the tank with 17 gallons of fresh 93 octane from Shell while my friend popped the hood and bypassed the MSD.

The car still didn't want to start and when it did, still ran like crap. We knew that the new optispark was to blame but just to eliminate every possible other problem we went by a parts store and bought a new coil and ignition module. We went home, swapped those parts, and low and behold it runs just the same. Defeated for the day I said screw it, I could feel the tickle in my throat getting worse anyway.

The trouble now was, I knew I needed to replace the opti, but if I was going to do this job again, I didn't want to have to do it a third time by gambling on another reman unit. OEM would be a no brainer except they are remans too. If I'm going to buy a reman I have a hard time justifying $400+ for it! So we started looking a little deeper into the MSD. What we learned was that although the early MSD units were indeed plagued with problems of bearing failure and rotors flying off, MSD has resolved the issue. Several people on the Camaro boards are spinning them to 8000+ with no trouble. I've always liked MSD and had no trouble with them (I know you don't like them Andy) but I decided to give them a shot. I figured if I am gonna be forced to spend $400+, it might as well be on something that is supposedly improved.

While I was ordering I also decided that although my plug wires were OK, they were about 8 years old and I wanted the coil wire to match. I COULD use the parts store wires I had, but I really don't like those. I've always run MSD wires but several years back they changed the Corvette set slightly. They used to have all 90* boots but they changed them to have a few that weren't. Although this was great for factory manifolds, it caused issues with my headers. The Camaro set included longer wires and all 90* boots, but the coil wire is too short because the Camaro has the coil on the opposite side. I know several people on that other forum which shall remain nameless swear by Taylor wires, so I started to look at them. I saw they had the "new" Thundervolt 50 wires. They are supposed to have the same low resistance as MSD but an even thicker insulating jacket, 10.4mm compared to MSD's 8.5mm. They also listed having two 180* boots, but I figured what the hell, I'll give them a shot.

The next day I got hit with the worst of what had to be the flu. I didn't move for 6 hours straight. Turns out my friend who helped me all day Saturday got sick too

Anyway, about mid week the magic brown truck arrived with the summit racing box. I opened it up and couldn't have been happier with what I found. The Taylor wires are HUGE, making even the MSD wires look like a joke by comparison. Despite their size they are also very flexible. I got out the old ohm meter and checked them out, sure enough they have a resistance right on par with MSD. I knew that if I could route them without touching the headers they would be awesome. Then I turned to the plain white box that simply said MSD Pro-Billet. I opened up the box and it was beautiful. The billet base is a work of art, putting the cheap pot-metal OEM piece to shame. The cap is beautiful with the MSD logo and an extra screw holding it down to provide for better sealing than the factory unit. The pigtail is permanently attached via a nice weatherproof grommet, eliminating another point of failure for the OEM unit. There is a timing adjustment screw that I will not really use because I can tune the computer, but it is large enough to not break and firm enough to not vibrate loose during operation. I removed the cover and made sure that the rotor was secure and the screws tight. I gave it a spin and it felt like a top quality bearing. I put the cap back on it and read over the instructions. They claimed it should be shipped at "0" adjustment on the timing but told how many turns it would take to get there from the fully tightened position. Wanting to leave nothing to chance I double checked this adjustment and found that they had indeed shipped it exactly where they said they did.

Saturday I set about with my new opti, plug wires, new plugs, and yet another set of water pump gaskets and even more coolant. Working alone this time and with my dad's borrowed Kerosene heater I set about the task. I knew the plugs weren't worn out, but with the severe pinging I wanted to inspect them for damage, so why put the old plugs back in? Afterall they would be the only remaining part of an otherwise brand new ignition system.

I made pretty good time, starting around 8am I was done by 3pm. Plug wire routing of the Taylor wires turned out to be no problem at all. After some time at the kitchen sink with some industrial strength Dawn I was ready to sit in the car and give it a shot. I knew from the instant I cranked it over that it was right this time. The battery had no trouble turning it over and it fired immediately and purred like a kitten. I took it for a spin and after letting it warm up decided to pound on it a little. 6500 RPM without the slightest hiccup? NO PROBLEM! The proverbial bat out of hell was back, and finally, after doing a pain in the ass job twice, everything is right with my soul again.

Only time will tell if the MSD Opti is worth a damn, but I really don't foresee any problems with it. My gut tells me it is a quality piece, and my gut is usually right.

Thinking about it I have determined that the hard starting was caused by the same issue as the pinging. Somehow, some way, this POS reman has the timing absurdly advanced. This morning I get to take on the real fun challenge, taking the part store POS back for a refund. They better not argue or they're gonna get one hell of a piece of my mind. They really owe me 6 hours of labor, two jugs of dexcool, and a set of water pump gaskets as well, but I know better than to think I'll get any of that. Why doesn't anybody take pride in their workmanship anymore?

Did you pull the engine codes during all this?

Opti's are funny, mine took 4 months to throw a code, it would shot off for 1 second on the highway once a week.

You hear the same story about the $130 ones even Cardone.

Thread from 2010 on my MSD:

http://www.corvetteforum.guru/modules ... id=131481#forumpost131481

But this year my 92 wouldn't run above idle after running 2 sessions on the racetrack.
No codes, went there the next day with a trailer and of course, the car started right up and ran fine,

tried it at the house, ran to 235 water temp, let it sit, drove 20 miles, let it idle to 235 again, let it heat soak, drove it again. Nothing, no codes.

So, I can't point a finger at the MSD. The only way to figure this out is to drive the car with a scope attached until it does it again. And I have too many other cars to work on right now.

IMO, the MSD is way better built than the GM but a new opti from GM would probably run another 70K.

It never set a code.

Most of the times, the opti won't set a code. The optical portion is very durable. Cap/rotor wear will cause more problems than the optical ever will.

I agree, Andy. Looking at what was left of my cap / rotor, I know it was the root of my misfire problem originally.

I have always felt the part had a pretty bad reputation and most of it wasn't deserved. I swear people will blame a flat tire on the Opti.

Mine didn't

it's a distributor, and the cap & rotor get dirty

a lot of times the optics get dirty, clean them & it works just fine.

Just make sure to check the bearing.

you can get away with that with the Gen II opti, but the venting in the OEM Gen I opti is so poor, the bearing is shit by the time 70k miles comes around. It does not take a lot of coolant to get in there and make a mess of things.

You know I converted to the vented style because it was cheaper and allowed better timing chain options but I never bothered to hook up the venting, also never even bothered to cap off the vacuum ports. There was absolutely no trash in the high voltage side, just wear from many miles.

When I get around to cleaning up the garage I'll take a look at the optical side and see how bad it is. I did at least put vacuum caps over the ports on the MSD.

Quite the ordeal! Nice thread and parts feedback. Hope it all works out from here forward.

Did you happpen take the new MSD Opti apart and

1. Check the rotor screw to make sure it was tight (I loctite them for GP)
2. Check the Cap O-Ring (they can be mis aligned)

These 2 things are the biggest problems with any new Opti-Spark and what the problems people were having with the first MSD's that were used.

You really should put the vent harness on it. I bought mine from GM Parts Direct when I converted my 92 to the late model Opti (using a new MSD OPti Spark) and have no problems since 2007. I turn mine over 7K every time I drive it....
Will

The Optispark vaccum harness I used, is GM PN 12555323.

$52.00 online.

It was a big part of the improvement of the Optispark II.... in addition to the better pin drive system and bigger oil seal.

You really need that vaccum harness to pull the ozone created from the high voltage side of the opti out of the cap.
Will

I converted to the second generation opti around 2001, 2002ish. Once upon a time I bought the vacuum harness and never got around to installing it, it's long misplaced by now.

The distributor has taken a lot of punishment over the years. Countless track passes and dyno pulls as well as being an all weather daily driver for many of those years.