I always used the AC Delco opti and never had a problem with the opti going out on me. Maybe I was just lucky to not have issues with the opti.

 

There's a reason no one uses the screw. It's an essentially useless feature.

 

It is worse than useless it creates a lot of additional room for error and failure.

The OP has a 94 which unless converted is unvented. IMO at that he should run a delco base with an MSD cap and rotor because that will add a vent for him.

To the few who swear the MSD complete opti is the way to go. What specific failures of the stocker did you have and at what mileage were they? Then has the MSD resolved those issues and how long has it been run?

We see a LOT of folks who neglect an opti for 100K+ than have a cap and rotor wear out. Then whatever they bought next that has been run for a fraction the mileage is automatically the best thing ever despite not having tested is as long yet?
Also rather laughable that the guy pushing the MSD turns a whopping 6200 when several others of us posting here are turning stockers nearer 7000.

The MSD cap and rotor seem good but there have been a lot of issues with the base. MANY opti "issues" can be traced back to neglect, unvented units, plugged vent lines, improper install, or just that they were wet and people bought into the blind opti hate without ever letting it dry out at which point it would have run again like any other distributor.

I have handled the MSD complete unit, took it off a guys car and put an AutoZone reman on to get the car running.

 

We went 9.90's with a stock opti before I converted to a regular dist.

 

This is an excellent string. I've been through a lot of opti issues, from stock to Chandler to Dynaspark. But I think the Delco opti with MSD Cap & Rotor may finally turn the trick. Actually, I meant Delphi as Delco no longer available, right?
My block is 1996 LT4 stroked to 396 by NuTech Motorsports (remember that guy Nick Norris? I actually got my motor, unlike some, and it's quite strong, no issues really. Should turn 430 rwhp with new stepped headers & TD's. Where to buy that Delphi? Any recommended venders? Thanks!

 

Truth. I bought one that cracked near the drive seal at ~500 miles. I have a friend that has 2 and swaps/rebuilds between the 2 when one 's the bed.

 

Thanks for sharing that...just what I needed as I wondered about matching Delphi to MSD cap & rotor vs going all Delco/Delphi or all MSD. THERE's a lot more shared here than I knew...like the problem could be a bad vibration/harmonic coming out of my engine...or the wrong length on the cam bearing. I'm going to check everything out discussed here. I did have great luck with the Delteq...ran perfect for years until the brain died & the company went out of business. My engine has been eating Opti ever since. I am lucky to get weeks, a few hundred miles...have bought Delco from GM Dealer, Chandler cheapie, but never tried the MSD. I shift around 6,700 but occasionally hit 7,000. I'm hoping the stronger MSD bearing will help. FTR I don't run anything extra like 6AL box. I do have an old Hypertech coil. Probably should replace with stock coil though it never affected the Delteq at all. .

 

Rebuild the one you have. I bought a reman from autozone and I made sure that it had the mitsu sensor. Then I ordered a cap and rotor from ebay for $25....been working ever since.

 

Wow, if you did that on a 383 and it worked I'm thinking for real my problem is not the Opti but a flaw in my engine or somewhere in the electrical system that likes to destroy opti's. Like I said I've gone through like candy. It can't be all bad opti's. At least one was 100% dealer purchased Delco factory. Not cheap either.

 

I doubt it....as discussed, all optis are **** other than a AC delco or MSD. Was the AC delco vented? Did you install the vent lines? (I feel many of my opti issues were from using the unvented version...GM redesigned the opti for good reason) AC delco also has at least a year warranty. I'd take it back to the dealership and get a return/replacement. Or try a MSD...

 

Yep. All my opti's have been vented as I'm running a newer 1996 block and yes the vent lines were installed.

 

Ok so I bought the msd cap & rotor kit for my unvented gm opti so it becomes vented. The msd instructions are vague. It doesn't say whether to reuse or eliminate the optical cover (the thin metal dish). Does anyone know what I should do?

 

Id personally reuse it

 

Ok so I did put the "dish" in and reassembled it but the think rattled around like a *itch so I bent the 3 small metal tabs so it fit snug. I think I'm good now. Not real impressed with these GM remanufactured optis...

 

Im pretty sure the msd one is made of plastic

 

The msd cap and rotor kit comes with the cap and rotor not the optical sensor cover or any other internals.