Question on replacement Opti-spark from CRT Performance

[Mel H.]

Wondering if any readers have any experience with buying from a speed shop out east called "CRT Performance, Inc". They offer a low cost Opti-spark replacement and I'm looking for one for my 94 vette.

Are others cheaper and certainly others more expensive, but looks like these guys have been in the parts biz for about 25 yrs and are offering OS's at around $100. Any inputs/reaction about them as a vendor would be appreciated... and/or other thoughts on replacement Opti-sparks.

Mel

[Joe R.]

Re: Question on replacement Opti-spark from CRT Performance

Mel,

My advise would be to spend the extra money and purchase a Delco/Delphi Opti Spark on E-bay for the lowest you can find it. The aftermarket Opti-Sparks cause error codes to be set in your computer and the light pops on. That may not happen all the time on all the after market brands but it does happen.

Just trying to save you some money and time in the long run.


JR

[Peter M.]

Re: Question on replacement Opti-spark from CRT Performance

Mel,

My advise would be to spend the extra money and purchase a Delco/Delphi Opti Spark. The aftermarket Opti-Sparks cause error codes to be set in your computer and the light pops on. That may not happen all the time on all the after market brands but it does happen.

JR

Changing out your Opti is a PITA so you don't want to have a part failure and have to do it all over again. I would recommend going with the OEM Delco unit and suggest that you be carefully on eBay as you really don't know what you'll get in terms of quality.

[Clem Z.]

Re: Question on replacement Opti-spark from CRT Performance

here is a GM one. http://www.jegs.com/i/GM%20Performan...0002/-1?CT=999

[Darrell S.]

Re: Question on replacement Opti-spark from CRT Performance

GM is the way to go

[Bill H.]

Re: Question on replacement Opti-spark from CRT Performance

Everyone who buys the cheaper Optis (or the Accel ones) has the pleasure of buying another one in less than a year. I'm a moderator on a C4 forum and hear it all the time.

The GM units are good but the 92-94 aren't vented and can be damaged by waterpump leaks or washing the motor.

BTW, the Jegs one shown is incorrect for a 94, 1994's still use the spline drive though some guys have said that they have a 94 with pin drive but i haven't personnally seen one.

The 92-94 Optis are more expensive too so, unless the car is going to be judged, the MSD Opti is a much better unit, is o-ring sealed at the cap and has a venting system.

And to make changing an Opti easier, get a power steering pump pulley puller/installer ($24). Removing the pulley gives you access to the plug wire connections on the left side and makes the job much easier.

[Peter M.]

Re: Question on replacement Opti-spark from CRT Performance

Everyone who buys the cheaper Optis (or the Accel ones) has the pleasure of buying another one in less than a year. I'm a moderator on a C4 forum and hear it all the time.

The GM units are good but the 92-94 aren't vented and can be damaged by waterpump leaks or washing the motor.

BTW, the Jegs one shown is incorrect for a 94, 1994's still use the spline drive though some guys have said that they have a 94 with pin drive but i haven't personnally seen one.

The 92-94 Optis are more expensive too so, unless the car is going to be judged, the MSD Opti is a much better unit, is o-ring sealed at the cap and has a venting system.

And to make changing an Opti easier, get a power steering pump pulley puller/installer ($24). Removing the pulley gives you access to the plug wire connections on the left side and makes the job much easier.

AND, while you are changing out your OPTI, you should replace the water pump.

I have a great How To write-up on changing out your Opti & water pump but its too large to post here. If you are interested send me your email address & I'll get the write-up to you.

[Bill H.]

Re: Question on replacement Opti-spark from CRT Performance

AND, while you are changing out your OPTI, you should replace the water pump.

I have a great How To write-up on changing out your Opti & water pump but its too large to post here. If you are interested send me your email address & I'll get the write-up to you.

And flush the coolant including pulling the knock sensors and flushing the block.

[Mel H.]

Re: Question on replacement Opti-spark from CRT Performance

Thanks very much guys. Appreciate the insight. Sounds like the usual story.. buying cheaper will someday make you wish you hadnt. This Opti was replaced about 2 yrs ago (40m mi), and I'm betting it was a cheaper one.

Pete.. I'll take you up on that offer for the 'how-to'. Never attempted this before so need all the 'how-to' I can get. I'll send a PM. And will do water pump, too.

I'm not dead certain its the Opti, but I'm not getting any spark at plugs, and cant think of what else it would be... unless you guys got more ideas or know of a way to verify??

Mel

[Bill H.]

Re: Question on replacement Opti-spark from CRT Performance

Mel, before you throw money at the Opti youneed to pull the codes. You can do it on the dash with a paper clip.

I have the procedure (in MS Word) and it's a bit long to post here, I can email it to you.

The reason you need to pull them is that no spark can also be the ICM (Ign Control Module) or the coil.

Pulling the codes will rule out or verify that the problem is the Opti.
Some parts stores can check the ICM (if you're lucky).

[Joe L.]

Re: Question on replacement Opti-spark from CRT Performance

Everyone who buys the cheaper Optis (or the Accel ones) has the pleasure of buying another one in less than a year. I'm a moderator on a C4 forum and hear it all the time.

The GM units are good but the 92-94 aren't vented and can be damaged by waterpump leaks or washing the motor.

BTW, the Jegs one shown is incorrect for a 94, 1994's still use the spline drive though some guys have said that they have a 94 with pin drive but i haven't personnally seen one.

The 92-94 Optis are more expensive too so, unless the car is going to be judged, the MSD Opti is a much better unit, is o-ring sealed at the cap and has a venting system.

And to make changing an Opti easier, get a power steering pump pulley puller/installer ($24). Removing the pulley gives you access to the plug wire connections on the left side and makes the job much easier.

Bill------


The first 5,000 or so 1992's built were equipped with an Opti-Spark which was not vented. However, all later 1992's as well as all 93-94 units were vented via three small holes in the bottom of the base casting. These vented units were also retrofitted to most early 1992's via recall.

The 1995-96 Opti-Sparks used a different venting system. This system involved vacuum extraction. However, they also use a different drive system. The 1992-94 were spline drive; the 95-96 were "paddle" drive. Retrofitting a 95-96 style Opti-Spark to a 92-94 requires that the drive system be changed, the front cover be changed, and the camshaft pin be replaced with a longer one.

I almost always prefer to use GM/Delco parts. However, I'm not sure that GM ever actually manufactured these Opti-Sparks. If they did, I suspect that ended after they were no longer required for PRODUCTION, especially after DELPHI took over most of GM's parts manufacturing operations.

The aftermarket Opti-Spark units that I've seen appear "suspiciously identical" to the ones packed in GM/Delco boxes.

[Bill H.]

Re: Question on replacement Opti-spark from CRT Performance

Bill------


The first 5,000 or so 1992's built were equipped with an Opti-Spark which was not vented. However, all later 1992's as well as all 93-94 units were vented via three small holes in the bottom of the base casting. These vented units were also retrofitted to most early 1992's via recall.

The 1995-96 Opti-Sparks used a different venting system. This system involved vacuum extraction. However, they also use a different drive system. The 1992-94 were spline drive; the 95-96 were "paddle" drive. Retrofitting a 95-96 style Opti-Spark to a 92-94 requires that the drive system be changed, the front cover be changed, and the camshaft pin be replaced with a longer one.

I almost always prefer to use GM/Delco parts. However, I'm not sure that GM ever actually manufactured these Opti-Sparks. If they did, I suspect that ended after they were no longer required for PRODUCTION, especially after DELPHI took over most of GM's parts manufacturing operations.

The aftermarket Opti-Spark units that I've seen appear "suspiciously identical" to the ones packed in GM/Delco boxes.

That's correct Joe. I should have been more precise saying that the 95-96 venting system is the way to go.
I usually buy Delco parts, but wouldn't think of replacing an early opti with another one that isn't vacuum vented.
The 92-94's can easily be trashed with a waterpump leak or washing down the motor. Partially because the 3 holes don't do a great job in removing all the moisture and partially because of the cap design with a paper gasket.
You can convert an early opti to vacuum vented with 2 fittings and a check valve (the Aftermarket guys even have a kit). But with the rising prices of the GM opti's, I always recommend MSD optis. Their housing is billet ,the cap is o-ring sealed, the spline drive is one piece (not removeable) and the 92-94 MSD comes with the vacuum venting system.

I pulled my MSD apart @ 15k miles and it looked brand new inside, have 22k on it now.

That being said, there's many GM units on the road with 100k miles on them.

[Terry M.]

Re: Question on replacement Opti-spark from CRT Performance

No spark in these engines can also be the coil to distributor wire. I had that condition once and it was corrosion at the coil tower, but many have reported a bad wire also. There was a time when the coil to distributor wire was available separate from the spark plug wire set from Chevrolet and Delco. Don't reach for the high-tech solution when basic mechanics still apply.

[Mel H.]

Re: Question on replacement Opti-spark from CRT Performance

Bill------

The aftermarket Opti-Spark units that I've seen appear "suspiciously identical" to the ones packed in GM/Delco boxes.

Tend to agree Joe. Seems illogical there would more than just a few places that actually produce them. But would agree a rubber sealed system sounds better than paper, so even though this car is all stock, I'll look at MSDs as I dont plan to have car judged anytime soon and prefer the assurance for those longer 'post-retirement' trips I hope to take soon . And 95-96 units sound like a better way to go.

But.. Terry makes a good point, I dont want to go to all that trouble and find it was just a wire, so thats where I'll start. Then I'll double check those codes.

BTW Terry... how'd you go about finding out it was the wire?

[Peter M.]

Re: Question on replacement Opti-spark from CRT Performance

Bill------
The 1995-96 Opti-Sparks used a different venting system. This system involved vacuum extraction. However, they also use a different drive system. The 1992-94 were spline drive; the 95-96 were "paddle" drive. Retrofitting a 95-96 style Opti-Spark to a 92-94 requires that the drive system be changed, the front cover be changed, and the camshaft pin be replaced with a longer one.

I almost always prefer to use GM/Delco parts. However, I'm not sure that GM ever actually manufactured these Opti-Sparks. If they did, I suspect that ended after they were no longer required for PRODUCTION, especially after DELPHI took over most of GM's parts manufacturing operations.

The aftermarket Opti-Spark units that I've seen appear "suspiciously identical" to the ones packed in GM/Delco boxes.

Joe:

I sent you a personal email transmitting the C4 LT1 Opti replacement write-up you asked me for. Its a big file, 10MB, so let me know if you have any problems downloading it.

P.