$70 dollar optispark
http://www.cnautotech.com/ShowPro.as...ID=876&ID=4569
http://www.ignitionpart.com/product.asp?Sort_ID=38
Also notice that same company makes the optispark units for Cardone AND MSD.
I put a new delpi unit from thepartsladi on my 94 and about 2 weeks later it went out from getting oil on it. I didn't have another $300 at the time to buy an OEM unit so I got one on ebay for about $100.
When I put the ebay opti in I also replaced the opti seals, which is probably why the other one went bad.
I drive it everyday and it has run great ever since.
It's a non vented opti.
I also have a 93 Z28 about 2 years ago the opti went out and I ordered a reman opti from summit for $249. I put it on the car and it would not fire, so I took it down to the shop and it turns out the drive mechanism was off 180 degrees, a defect of the manufacturer.
$600 later I installed a new GM opti and it has worked great since.
Summit refunded me for the opti, but I was not reimbursed for any labor.
Before that a chandler opti would not even start....
i am new to c4, but above info is from PO.
Maybe it is time for a cardone unit from auto parts store down the street, at least I will not have to pay return shipment .........
BTW, OP, thanks for your post!





