Airbornec507

I'm just curious as to what could have caused my first 3 opti's to destroy themselves internaly. I'm running the delteq system now and everything runs fine for the most part accept for random misses at times. Cam dowl pin length is fine.

Here's what I am thinking could be causing it.

112 LSA installed on a 109 centerline instead of the recommended 108 thus 3 degrees advanced.

So question is could the cam being set up like this cause the opti to be out of position for the spark events?

Just some random data that may or may not influence your response:

DCR 8.4
SCR 11.3
Heads milled 50cc's
1995 OBDI

I was thinking of eventually picking up a dynaspark but if the cam is degreed weird then a better opti realy isn't going to help any. Maybee the cam position has nothing to do with it I don't know. That's why I'm asking. Thanks!

Stl94LT1

Cam degreeing shouldn't have any different effect on the opti. Are you sure the camshaft dowel pin is the correct length?

shoebox

Yep, it's the most common cause of repeated opti destruction.

Airbornec507

If .650" is correct then yes. I did have to grind it down some.

Stl94LT1

Copied from "shoebox" site.

GM specs indicate that the dowel should be .620" long (protrusion from the front face of the cam) for the vented optispark. Some people have said it is supposed to be .685". Mine was actually .650" and still was in no danger of bottoming out in the optispark drive (I'm thinking .685" might be the max it could be).

HottestZ28

not to hi jack but when you order a cam and it says 92-97 LT1 what exaclty do you need to do in order to get correct dowel pin length?
Looking into CC503 or CC306

marshall93z

I cut/ground mine down to the right length.

shoebox

It would not hurt to double check the pin to opti clearance with some clay.