Need good Optispark Replacement Write up
Safety Car
Joined: Aug 2002
Posts: 3,842
Likes: 230
From: SANTA CRUZ CA
Drifting
Joined: Aug 2010
Posts: 1,704
Likes: 8
Just 30 seconds before my post...
ok good link
http://forums.corvetteforum.com/c4-t...-pictures.html
ok good link
http://forums.corvetteforum.com/c4-t...-pictures.html
Race Director
Joined: Sep 2001
Posts: 14,659
Likes: 749
From: NEwhere Ohio
I dont want to see you do the job twice:
I really hope you didnt (or dont) buy one of the cheapo ebay optisparks. Even the $500 MSD optispark is a POS in my opinion.
Spend the money (prob about $750), search long and hard, and buy an AC Delco new old stock unit.
Your time is worth it.
I also recommend adding a vented cap ($250) from a later model gen II (found on 95-96 vettes) and a vented harness.
Once you do that, it will become completely reliable.
Also..theres lots of theories on this:
If you current waterpump is fine, then continue to use it. The new AC Delco waterpumps are made in china and not as good as your old one.
If you continue to use your old one, you can add a fitting to the weep hole to attach a hose so that it doesnt spew water on your new optispark when it goes bad.
Once the seals on your optispark break, water intrusion can become a problem.
Good luck
I really hope you didnt (or dont) buy one of the cheapo ebay optisparks. Even the $500 MSD optispark is a POS in my opinion.
Spend the money (prob about $750), search long and hard, and buy an AC Delco new old stock unit.
Your time is worth it.
I also recommend adding a vented cap ($250) from a later model gen II (found on 95-96 vettes) and a vented harness.
Once you do that, it will become completely reliable.
Also..theres lots of theories on this:
If you current waterpump is fine, then continue to use it. The new AC Delco waterpumps are made in china and not as good as your old one.
If you continue to use your old one, you can add a fitting to the weep hole to attach a hose so that it doesnt spew water on your new optispark when it goes bad.
Once the seals on your optispark break, water intrusion can become a problem.
Good luck
Pro
Joined: Aug 2007
Posts: 668
Likes: 38
From: Austin TX
That is a good link. However, you don't need to remove the throttle body to do the job. Also, here is a link on how to remove the harmonic balancer.
http://forums.corvetteforum.com/c4-t...-balancer.html
http://forums.corvetteforum.com/c4-t...-balancer.html
Pro
Joined: Aug 2007
Posts: 668
Likes: 38
From: Austin TX
Here is the water pump weep hole mod
This is how I created a drain hose for the water pump on my 92 LT1.
I first measured the weep hole in the bottom of the water pump.
I determined a 3/16" barb to 3/16" barb brass connector from Home Depot would fit in the hole if I decreased the diameter.
I chucked the connector up to the center stop in my high speed drill and laid it across a flat file. Spinning the connector against the file, I decreased the diameter of the barbs until they were just slightly larger than the weep hole size. I froze the connector, put a little sealant on the barb closest to the center, and used a small hammer to drive the connector up to it's center point. Put a hose on it and routed behind the Optispark wires.
Now when the water pump blows out, it will blow out to the ground and not all over the Optispark.
I first measured the weep hole in the bottom of the water pump.
I determined a 3/16" barb to 3/16" barb brass connector from Home Depot would fit in the hole if I decreased the diameter.
I chucked the connector up to the center stop in my high speed drill and laid it across a flat file. Spinning the connector against the file, I decreased the diameter of the barbs until they were just slightly larger than the weep hole size. I froze the connector, put a little sealant on the barb closest to the center, and used a small hammer to drive the connector up to it's center point. Put a hose on it and routed behind the Optispark wires.
Now when the water pump blows out, it will blow out to the ground and not all over the Optispark.
Last edited by mixalive; Jan 13, 2014 at 11:39 AM.
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Race Director
Joined: Sep 2001
Posts: 14,659
Likes: 749
From: NEwhere Ohio
Im happy yours is working.
If you make it past 10k with it, perhaps its a good one?
I wish I did the waterpump weep hole mod.
MSD is not the company it once was. They got bought out for their name and are not servicing their products. There is not any attempt anymore to 'improve' or 'work out bugs' on this product.
Sure they wil hand you another piece-of-junk one if you complain, but that doesnt get you anywhere.
Heres some issues with MSD optisparks:
________________________________________
Just a quick list of MSD optispark failures:
There are some that seem to work. But why take the risk?
At a minimum you'll have 6 hours (more if MSD sends you another defective unit) in labor replacement.
Worst case, could you imagine this thing breaking down on you in a busy construction zone without berms to pull over?
http://forums.corvetteforum.com/c4-t...e-box-bad.html
http://forums.corvetteforum.com/c4-t...d-is-junk.html
http://forums.corvetteforum.com/c4-t...is-vs-msd.html
http://forums.corvetteforum.com/c4-t...celerator.html
If you make it past 10k with it, perhaps its a good one?
I wish I did the waterpump weep hole mod.
MSD is not the company it once was. They got bought out for their name and are not servicing their products. There is not any attempt anymore to 'improve' or 'work out bugs' on this product.
Sure they wil hand you another piece-of-junk one if you complain, but that doesnt get you anywhere.
Heres some issues with MSD optisparks:
________________________________________
Just a quick list of MSD optispark failures:
There are some that seem to work. But why take the risk?
At a minimum you'll have 6 hours (more if MSD sends you another defective unit) in labor replacement.
Worst case, could you imagine this thing breaking down on you in a busy construction zone without berms to pull over?
http://forums.corvetteforum.com/c4-t...e-box-bad.html
http://forums.corvetteforum.com/c4-t...d-is-junk.html
http://forums.corvetteforum.com/c4-t...is-vs-msd.html
http://forums.corvetteforum.com/c4-t...celerator.html
Last edited by dizwiz24; Jan 4, 2014 at 02:12 PM.
Race Director
Joined: Oct 2011
Posts: 16,079
Likes: 816
From: Dallas Texas
2025 C4 of the Year Finalist - Modified
This is how I created a drain hose for the water pump on my 92 LT1.
I first measured the weep hole in the bottom of the water pump.
I determined a 3/16" barb to 3/16" barb brass connector from Home Depot would fit in the hole if I decreased the diameter.
I chucked the connector up to the center stop in my high speed drill and laid it across a flat file. Spinning the connector against the file, I decreased the diameter of the barbs until they were just slightly larger than the weep hole size. I froze the connector, put a little sealant on the barb closest to the center, and used a small hammer to drive the connector up to it's center point. Put a hose on it and routed behind the Optispark wires.
Now when the water pump blows out, it will blow out to the ground and not all over the Optispark.
I first measured the weep hole in the bottom of the water pump.
I determined a 3/16" barb to 3/16" barb brass connector from Home Depot would fit in the hole if I decreased the diameter.
I chucked the connector up to the center stop in my high speed drill and laid it across a flat file. Spinning the connector against the file, I decreased the diameter of the barbs until they were just slightly larger than the weep hole size. I froze the connector, put a little sealant on the barb closest to the center, and used a small hammer to drive the connector up to it's center point. Put a hose on it and routed behind the Optispark wires.
Now when the water pump blows out, it will blow out to the ground and not all over the Optispark.
Le Mans Master
Joined: Jul 2009
Posts: 6,381
Likes: 66
From: SF bay area C.A.
C4 of the Year Finalist
I really can't see paying $500-700 for an opti. I put in a Chandlers [$135] and it's been running like a top. Also would like to add this is an autoxcar and gets wound high quite often.