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While I have not used one, Petris seems to have solid reviews. Unfortunately, it's a complete crap roll on the cheap clones available today. Long gone are the AC Delco with Mitsubishi sensor. If you have a original Opti, keep it and just replace cap & rotor with a Standard Motor Products one (yes the more expensive one)
 

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Watch this...

They are notoriously bad "new" from eBay and other places. They are no longer manufactured correctly. Specifically, the pressed in rotor bearing is not installed correctly and will make the timing advanced or retarded.

After I installed a "new" opti, the SS would start, run then stall out once it reached operating temps. Advancing the timing by 5 degrees through the PCM, kept it running. I swapped the "new" opti with an old one that I knew worked. Problem solved.

Same happened with my 9c1 I race. Two different "new' optis failed to work. One from RA and the other from eBay. Had to get a used one from a friend to get it running.

Just to add more to "new optis are garbage", my buddy had to swap his opti with three different "new" optis from eBay before he got one that worked.
 

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+1 on all the Opti advice. I just changed my cap and rotor out today since my car was running like garbage under heavy throttle. I bought the expensive Standard Motor Products one, It seems to be good quality and though I haven't had a chance to drive it yet, it does run great so far. I'm still running the factory distributor underneath with the Mitsubishi sensor. Personally, I'd try and peruse a few junkyards and try to find some LT1 cars (though you may not have any luck nowadays) to pull the Opti off of, the idea here being to try and find an OEM Mitsubishi optical sensor. They are not invincible, but miles better than any "new" replacement and will likely still work great. I understand if that's a bit much tho lol.

As for the water pump, that is the true Achilles heel of the LT1 IMO. Essentially, there're almost all the same and most are not great. I'd just get one with a lifetime warranty and run a hose from the weep hole away from the distributor. They tend to leak coolant out the weep hole on the bottom, all over your Opti, and give it some hard times. But, with the pump off, the hole can be drilled and tapped for a small hose nipple fitting, so you can reroute the coolant leakage away from sensitive parts and ignore the leaky water pump for a long time, as it seems that the seal inside is what tends to fail, not so much the bearing.
 

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I bought an MSD Opti years ago assuming it was as good as their C&R was back then. It turned out to be a wallet draining item. Car had a stumble at high RPM so I chased and replaced several other parts "assuming" my MSD exploding wallet opti was the shiat and was good. I finally put on my original I was keeping as a spare and no issues since. I sent it back to MSD for the $100 fix they offered and received a new unit. I immediately sold it

Now I understand based on several bad reviews on z28.com that MSD has since gone offshore and things have just turned to complete shiat with the MSD unit. The moderator, Fred aka Injuneer, of that forum had spent endless hours working directly with MSD tech in resolving issues to no avail. It appears MSD has simply gone offshore and their Opti is as crap as the no name ebay shiat

While I have no experience with them, Petris, is the one to go with based on reviews

It appears (link) the pin drive units will be available in a few days

Again I have no direct experience with the Petris unit but if I had to get a Opti today...I would get it

I agree the stock WP is the primary culprit to kill an otherwise good Opti. If the Opti does get coolant or oil in it from WP drive seal leak it can be "carefully" cleaned and fixed. I have done that

After getting 8 optis replaced under new car warranty due to WP fails mostly (last 3 died because Mr Goodwrench put Opti vent harness check valve on backwards causing crud condensation build up in 500 mi) when my car was new...I went Meziere EWP 22 years ago. I still have the then 8th real AC Delco opti which is now my spare as the bearing now is "slightly" lose causing oil to get in in very slowly and am using the REMY Opti thepartslady sold back when (no longer available) which has a Mitsubishi Opti and it has worked fine for years
 
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