30th droptop

iTrader: (-1)

My son's 94 T/A threw a Code 16, and I'm expecting we'll be replacing yet another Opti. The one in there is the third in five years. It's a Delphi, and it lasted four years (but only about 20K miles). I'm tired of replacing Optis, and, assuming this Opti needs replacement, I'd like this to be the last Opti we put on the car.

I've read a lot of threads about which Opti is best, and it seems like the more I read, the more uncertain I become. I'm hoping that if I give some specific information about my situation that some of you gurus can provide some specific direction.

The car is just a regular street car with 130K miles. It's an extremely well maintained, very nice car. I'd like to see it go to at least 200K. My son sometimes drives some long distances, and Opti failure could really be a bummer 100 miles from home. The only thing I'm after is reliability. The car won't be raced or anything like that.

I'm willing to pay MSD prices if it means I'll be getting a better quality unit. I'd prefer not to go to the expense of Delteq, but I would do it if I thought it would significantly increase the life of new Opti.

hrcslam

Have you converted to the vented opti? What coil are you using? The MSD should make the conversion to vented easier.

The delteq helps by removing the spark from the cap and rotor and therefore ozone from the opti (which is what ruins them). The early model optis were not vented, the later models were. What GM did was introduce fresh filtered air via the intake tube to the opti that vented through the cap and rotor via intake manifold vacuum line. This pulled the ozone away from the optical sensors.

IIRC, 1994 was none vented. Converting to vented should help here. Going with the delteq will require the code 16 to be fixed as it still uses the optical sensors.

Have you already confirmed that the wiring is good? When you replaced the opti, did you replace the harness too?

30th droptop

iTrader: (-1)

I did not convert to a vented cap last time. One thing that was appealing about the MSD Opti is that the 94-back unit is already converted to allow for venting. At least that's what I've been told.

I replaced the harness at the last Opti replacement. I have not had a chance to look at the car thoroughly, but I doubt I'll find any connection issues. I will verify Opti failure before I actually buy parts.

The coil is a standard BWD replacement unit. It was replaced a few years back.

BTC

I suspect if numbers were available, the failure rate of MSD would probably be much higher than AC Delco or Delphi.

The factory opti on my '94 lasted for over 100K miles, and would have probably lasted quite a bit longer had the water pump not started leaking onto it, which is something you may want to check.

There is a GM High Performance article floating around somewhere on venting an unvented opti. I can't seem to find it, but this article appears to contain a lot of the same information, http://www.superchevy.com/how-to/16758/

96capricemgr

iTrader: (1)

MSD cap and rotor kit adds venting without the extra compexity and failure rate of their base.

hrcslam

It may be worth taking the opti out and cleaning it. The vent mod is worth it. Usually the opti, if it's OEM, is just dirty from oil or coolant getting inside of it. That's not to say they don't fail (all things fail), but the actual failure rate is much better than rumored. Cleaning the opti had fixed mine a few times.

30th droptop

iTrader: (-1)

Great information. Thanks guys. I will definitely be doing a cap modification to add a vent or using an MSD cap. I should have done this in the first place. I would hope that the problem is just a contaminated optical sensor/wheel; however, my son can't afford to have much down-time on the car. I'll want to try to finish the job in a day. If a new Opti is needed, I want to be able to slap it on right then and there. Maybe I can order one from a place where I can return it if not needed?

From what I hear, if I go with a stock unit, I'll want to be sure it has a Mitsubishi sensor in it. The Opti in the car now is a Delphi. Because of the short life, I'm wondering if it had an Mitsu sensor. If I buy a new AC Delco or Delphi, will it have the Mitsu sensor? The original Opti lasted 110,000 miles. I'd like to get one with true OEM quality.

hrcslam

IIRC, all optisparks are rebuilt now (not new). I'm not sure what optical sensors they use.

Rockauto has good prices on optis, but I'm not sure on the return policy.

Dirty_Bird

My msd optis ran good, just the one i forgot to loctite the rotor on and came off at 6k+ rpm. Other than that ran without missing a beat

lt1_80_corvette

PETRIS Opti has IMO the best opti. I dont have the money this go around but will be buying it as my next purchase. I went with Saccitycorvette which has new opti's for a good price.