how to go vented
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how to go vented So i think my opti just went out cause my car wouldn't crank only turns over. I need to go out and check the voltage from the opti to the pcm tomorrow when the weather is better. I havn't used the car in a week and tried starting it yesterday durring the rain, but only turns over. I don't feel like puting another non vented POS in my car again thats only gonna last me 2 years. Can anyone fill me in w/ part #'s and everything i need to convert it to the vented kind. thanks
So i think my opti just went out cause my car wouldn't crank only turns over. I need to go out and check the voltage from the opti to the pcm tomorrow when the weather is better. I havn't used the car in a week and tried starting it yesterday durring the rain, but only turns over. I don't feel like puting another non vented POS in my car again thats only gonna last me 2 years. Can anyone fill me in w/ part #'s and everything i need to convert it to the vented kind. thanks
On top of that, you need the vented opti (of course), vacuum lines (12555323), electrical harness (12130319), new 95+ timing set (cam gear is different), a '95 timing cover (10214196), and one new intake fitting (14082470).
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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:
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 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
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i was recomended to this site http://www.eficonnection.com dose anyone got more info on this?
And you don't need to switch cams, but you do need to switch the dowel pin to the longer style, which more times then not would be easier to get a cam from someone with a newer vehicle who upgraded (and so they have their stock cam that is of little use to them anymore). The pins can be very hard to remove, as was the case with the B-Body cam we got that we were putting in a TBI motor, for that we had to shorten the dowel, and trying to tap it in or pull it out didn't happen, so we just cut it to length heh
I haven't heard but maybe a handful of horror (not even horror really) stories with MSD cap and rotors, so that'd bet he route I'd go
Just thought of it, but anyone know if you can swap the opti drive shaft out of a newer style to the splined that us older style have?
They've apparently gone down hill. The Optis are still decent, but apparently not as good as originally, and their customer service has also totally gone to pot according to a few who've had to deal with them. That is if they get customer service heh
Good thing I have an older unit. 
I think the "redesigned" MSD is a really good piece too. I wouldn't hesitate to loctite the rotor screws and run that unit as well.
My buddy has it on his car and it seemed to run the car better than the stock opti and is holding up great!
I think the "redesigned" MSD is a really good piece too. I wouldn't hesitate to loctite the rotor screws and run that unit as well.
My buddy has it on his car and it seemed to run the car better than the stock opti and is holding up great!
There's a huge thread on it.
And you don't need to switch cams, but you do need to switch the dowel pin to the longer style, which more times then not would be easier to get a cam from someone with a newer vehicle who upgraded (and so they have their stock cam that is of little use to them anymore). The pins can be very hard to remove, as was the case with the B-Body cam we got that we were putting in a TBI motor, for that we had to shorten the dowel, and trying to tap it in or pull it out didn't happen, so we just cut it to length heh
I haven't heard but maybe a handful of horror (not even horror really) stories with MSD cap and rotors, so that'd bet he route I'd go
Just thought of it, but anyone know if you can swap the opti drive shaft out of a newer style to the splined that us older style have?
They've apparently gone down hill. The Optis are still decent, but apparently not as good as originally, and their customer service has also totally gone to pot according to a few who've had to deal with them. That is if they get customer service heh
And you don't need to switch cams, but you do need to switch the dowel pin to the longer style, which more times then not would be easier to get a cam from someone with a newer vehicle who upgraded (and so they have their stock cam that is of little use to them anymore). The pins can be very hard to remove, as was the case with the B-Body cam we got that we were putting in a TBI motor, for that we had to shorten the dowel, and trying to tap it in or pull it out didn't happen, so we just cut it to length heh
I haven't heard but maybe a handful of horror (not even horror really) stories with MSD cap and rotors, so that'd bet he route I'd go
Just thought of it, but anyone know if you can swap the opti drive shaft out of a newer style to the splined that us older style have?
They've apparently gone down hill. The Optis are still decent, but apparently not as good as originally, and their customer service has also totally gone to pot according to a few who've had to deal with them. That is if they get customer service heh
The drive mechanism between the two optisparks cannot be interchanged.
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No, you need a NEW CAM. There are two differences that need to be addressed. Most people know about the drive pin (switching from a .300" pin to a .700" pin). But vented optisparks have a longer snout that engages the camshaft deeper than their non-vented counterparts. The 92 to 94 camshaft has a shallow tapered hole. You need a new cam, period. Don't even try to debate it.
The drive mechanism between the two optisparks cannot be interchanged.
The drive mechanism between the two optisparks cannot be interchanged.
Would a machine shop be able to accommodate the factory cam if the correct dimensions were provided for drilling?
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lol mybad fixed... ya but i need an opti that will last for 5+ years. if i could get rid of it completly i would spend the money and never worry about it again.
