non vented to vented opti?
If you want to change to a vented from non-vented, you have to do many things. It may not be cost effective unless you are doing a cam swap at the same time.
Besides the optispark itself (GM p/n 1104032), you need:
- 95 or later timing cover [1995 front cover (includes round seals) GM p/n 12552426]
- late model or aftermarket cam (or have your cam modified by drilling the hole in the front to the proper size [.500"dia. X 1.0625" deep] and a longer dowel pin added
- 95 and later optispark electrical harness GM p/n 12130319
- optispark vacuum harness GM p/n 12555323
- vacuum fitting [GM p/n 14082470] or "tee" to provide vacuum for the opti
- 95 or later timing set components (or at least the cam gear) cam gear (GM p/n 10206039), crank gear (GM p/n 10128346), chain (GM p/n 10128485)
- timing cover gasket GM p/n 10128293
- water pump gaskets [2] GM p/n 10128343
- intake manifold gaskets if you are pulling the cam GM p/n 12524653
Or you can put an MSD cap/rotor kit on it and essentially have a vented opti. They come with their own and similar venting system.
Hey:
They have advantages, the vented over the non, but unless you are doing a cam, EWP and timing cover upgrade, it may be cheaper to buy a real GM OPTI and a MSD cap and rotor as the MSD caps come with a vent kit. Also the reason you can find the Accel one so cheap is they are, and not highly thought of by many. @1 time they had a unique failure rate or complications that could not be explained away, except when you changed out that Accel OPTI the probs went away. The caps themselves are not bad but in no way would I go through an OPTI change to put on one of them. It's not worth it, to take the chance of complications later on. Other than the GM OPTI the only really proven reliable OPTI is the DYNASPARK. but they are not dirt cheap. You gets whacha pays fur, as they say around these parts. MSDs can be hit or miss, I keep one as a spare for my daily as I bought it and then went to the DYNASPARK and LTCC on my other car. My 270,000 Miles daily has a real GM OPTI with a MSD cap kit on it. Good Luck with whatever you choose.
Dub
Last edited by 1993 z28 f1; Aug 19, 2010 at 07:22 PM. Reason: updated
btw thanks for the reply's very helpful
edit: could i just cap the vents on the opti? this car only get driven about 1,000 miles a year an never in the rain
Last edited by keeven1320; Aug 19, 2010 at 07:56 PM.
btw thanks for the reply's very helpful
edit: could i just cap the vents on the opti? this car only get driven about 1,000 miles a year an never in the rain
I would not totally cap a vented opti. Even the non-vented one actually has some vents on the bottom. It just does not use vacuum for a positive venting system.




