AC Blue 66

Read what I posted again, I'm surprised they didn't use coils when they designed the LT1, prior to its release. They were using coil packs on cars in the 80s

Renfield

Exactly.

aklim

People are usually stupid and will buy slogans like "Quality is job 1", "Heartbeat of America", etc. They even believe that one politician cares more for them than others. I accept that a business is there to make money. Anything else is part of the effort to sucker you in to make money. Still, it seems people need to have something to believe in.

Renfield

The Optispark helped achieve oppressive emission goals and worked good enough. It's all about the Benjamins.

Here's a trick question. GM mounted the heat sensitive ICM to the engine block on the LT1. Was that the optimal location or did it save XXX seconds on the assembly line?

aklim

OMG. I should have bought a Ford where quality is job 1 or a Mercedes where they are engineered like no other car in the world or lately, The best or nothing. Should I also have bought shares in the bridge someone was offering?

FAUEE

Most of the "Low quality optis" are people that either never had an opti problem, or didn't get the water pump sealed. A lot of icm and vats issues are misdiagnosed as opti issues.

v8vette84

I am another who has stuck old sensors in new housings. I bought an optispark on amazon, replace the cheap junk sensor with a used OEM unit and sealed the opti back up with RTV. The seals on the opti cap never left me feeling really good that they sealed 100%.
My Corvette is using a chandler motorsports unit with no issues
I have had 2 96' L99 Caprices with oem sensors with 0 issues. One with 200k+ and one with 100k.

Opti issues are blown out of proportion BIG TIME. Have a buddy who complained about the opti but I found out he kept on putting in advance auto units. I told him to bite the bullet and buy a quality opti and the problems vanished once ho bought an MSD. (even though the MSD is not known to be that great either) It's still working though!

Chandler motorsports units used to be decent but it sure is a crap shoot. Someone needs to have an opti built to factory quality/specs and the LT1 owners will flock to that opti. I too saw the thread where the guy opened up the cheap optical sensor and found bad solders. Fixed the joints and it worked again. It's too bad those junk sensors are all over the market... Such a simple issue to resolve in the manufacturing process but it costs a few more pennies per sensor.

MatthewMiller

I agree with those who say that the complaints about the Optispark are generally overblown. A lot of people immediately assume their opti has gone bad as soon as they have any problem, and usually it turns out to be something else. Ditto for the people who think the LTx engines are so terrible: they produced them for five years in millions of vehicles and they comprehensively outperformed their predecessors. Yes, the LS series is better, that's a given with the years of development and pressure for better emissions and efficiency. But likewise, the LTs are better than the Gen-1 SBCs that came before them. Any back-to-back comparisons make that obvious, and any attempts to repair or tune the engine management systems on L98s will, too.

The 95-97 vented optis addressed the biggest issue with these distributors. So I would narrow my serach to 95-96 C4s. On the flip side, the 96 C4s are the first year for OBD2, and they are therefore subject to more stringent emissions inspections in some locations. There is also now only one software suite that you can use to tune them. So, if you think you'll be doing significant powertrain mods, you might want to avoid the 96s.

aklim

​​​​​​LT can be converted to a LS system but why? Might as well go with the better one.

MatthewMiller

Why convert a perfectly good-working opti to something else, especially for daily-driving use on a stock or near-stock C4? The question was whether or not an optispark distributor is a problem for a daily driver C4. The answer is, not really, and especially not with the 95-96 cars.

If the OP's other choice is an early C5, he'll pay more than twice as much for a car in similar condition. And as noted previously, the C5s aren't immune from issues. And in some ways, C5s are harder to work on; whereas swapping out an opti isn't as hard as some people make it out to be. The bottom line is that I would not let the prevailing paranoia about optis scare me away from a C4 purchase, especially a 95-96 example with fairly low miles.

Kingtal0n

You have to pull the balancer off to get to the opti?

my words... how is that not a big deal... I'd rather set the lash on all the rockers than yank a balancer from a V8 in a car

I think the fact so many people who still use the optispark showed up with personal methods and trial-error details is a strong sign all by itself, while nobody that's ever gotten rid of one is even paying attention to the forum section...

PatternDayTrader

Its not pressed on. It comes right off unless its stuck, and even then it comes right off after its unstuck.

Kingtal0n

I just really annoyed at the thought of taking the balancer off an engine, especially V8 engine (they tend to be larger I guess) and especially tight car areas. I've broken a 3-jaw puller on a balancer and had many an hour wasted because of not having the exact perfect tool to deal with it. Having to get the perfect tool and be an expert at pulling the balancer is a turn off for the optispark, is IMO.

aklim

For stock, sure. You are absolutely right. Later, if the mod itch hits, well, you got to consider that could happen. Many a couple decide they don't want to have kids and suddenly one of them decides against or gets pregnant.

I agree it is going to cost more to get a newer and better model.

No car has been, is and will ever be immune to issues. That is the way that goes. That said, when I go to a Chevy dealership and have an older L98 or my buddy's LT1, it is kinda annoying when you have an LT or L98 specific issue and you are told that there are one or two "specialist" for that motor and the rest don't want to touch it. I have seen that "specialist" title before. It means "you know a little more than we do and we palm it off to you. Tag, you're it."

aklim

Could care less. Those are jobs I could palm off on someone. It isn't that much harder to let them "specialists" have the job. That said, just because I am willing to have someone tune it doesn't mean there is someone who wants to so I am forced to the "guess a tune" unless I am willing to cart it hours away. THAT is my turn off.

v8vette84

Again the balancers are not pressed on. 3 Bolts and it pops right off unless its got a bit of rust on it. Regardless it's pretty easy to do. What perfect tool are you referring to and you don't want an opti just because the balancer needs to come off? If you think taking the balancer off is tough I would imagine you don't work on your own cars anyways... Clearly you haven't done the job and you keep comparing the LT1 balancer to an older press on balancer which is a misdirection. I could see no way to break a puller just taking the balancer off an LT1. Mind you I'm not talking about the hub itself as that can stay on while doing the opti.

Bottom line: The opti is easy to remove. I have done it plenty of times.

Renfield

Geez, you make it sound like a five minute roadside wrench job. Getting that effing balancer off both my '95 AND '96 was literally a months long exercise in frustration. Hose down with PB blaster, pound with hammer, rotate, repeat.

The '95 left my wife stranded, and it was a failed optispark. My '96 Opti got soaked by the water pump, but was still working. When I took it apart one screw had backed out of the rotor, and the bearing had play, so it was time anyway (at 95K miles).

I turn 60 this month, have been working on my cars/trucks/tractor/mowers/motorcycles all of my life. I don't claim to be god's gift to wrenching a car, but I'm not helpless. And I'm here to tell you that mother grubbing balancer was a major bitch to remove.

Because a failed optispark will leave you stranded, a '92-'96 probably makes more sense as a DD than a long distance car. I'm still reluctant to drive mine out of town. Twice bitten.

PatternDayTrader

Don't take this wrong but you were either doing something wrong or you were handicapped by not having the right tools.. No matter how stuck, it should never take more than a few minutes to remove it.

aklim

I'm curious. What is the book time on the job?

Renfield

I know it shouldn't. But it did. Twice. Despite all the best advise I could dig up about the job on this forum. The second one I did (the '95) was harder than the first.

I would starve as a mechanic no doubt. And I'm sure a two-post lift would make the work much simpler. Maybe even a half day job the second time around.

Crawling under the car on jackstands gets old really fast. My bones were only 58 at the time. And it was very dark down there. I don't have the kind of service bay this car really requires. Most days it seems like every stinking bolt on this car needs a special tool.

I coated the balancer well with anti-seize, so I expect round 2 to go better.

I'm very stable and, like, a genius too.