I guess i am going to convert to the vented style. I was looking at diagrams and the mechanic kept saying that there was a sensor in the optispark thatthe ecu needs to see. Dont know how true this is.

 

Yeah, the sensor is the optical reader. All opti's have that.
You're getting some misinformation from your mechanic, but do what you want.
To update to the newer style vented opti, you need to alter your cam because the drive mechanism for the opti is different, as well as needing to change over the timing chain cover to the new style. Did you even try rewiring the 92 opti yet?
Read this: http://www.gmhightechperformance.com...ing/index.html, pay special attention to the part about half way down the page titled "Same System, Different Look". Read it twice if you need to.
And when using the old style opti, it would be a very good idea to convert it to be vented. Here's a DIY article on how to: http://www.corvettefever.com/howto/16758/index.html

 

listen to 69.
http://www.nookandtranny.com/Info_LT1.html

 

this is the guide i gave them http://www.fierolt1.com/lt1_95_up_OptiReplace.htm


I told them what to do but I am in a jam. All the info and links you guys are giving I read those last week, so I know you guys arent giving me bad info. I gave him the idea about changing the harness like you said Camaro 69 but he swears the car wont fire correctly. Im almost at their mercy because he car is too complete to say **** it and tow to another shop plus no I wll hold him responsible if the car doesnt want to fire. I only pay with visa credit cards so if something goes wrong I can do a chargeback and visa has me covered. The harness swap made sense to me but when the mechanic pulled up some diagrams he was convinced it would not work

 

Car has some heavy backfiring. timing is good. spark plugs good

 

double, tripple check to make sure the plug wires are in the correct order. only takes one.

 

they are all correct as well

 

So which way did you wind up going, the 92 opti with the harness change, or the new style opti with the timing chain cover swap? And who did it?

 

went with the harness change. I called nook & tranny and explained my situation I also told Brent my friend (camaro 69) told me to do the harness swap because he did it in his vette. He said that the way I did the harness would work for the 92 vette engine harness but may run into issues with the 95 z engine harness. I believe he said something about them having to be sequential. He didnt try to sell me their 93-94 harness but more so was genuinely giving me solutions.

The car will run for about 2-5 mins idling perfect and then the backfiring starts.
So i have narrowed it down to:
1. bad opti, even though the motor was new the opti could be bad. (May need new one)
2. Harness swap I did may have been done wrong (May need to purchase 93-94 opti harness. 100% assured it will work by nook and tranny
3. Plugs installed in incorrect order?

hopefully its one of 2. or 3. hope its not all 3. my pockets spirits are beat. im so close to finishing this. any ideas because im all ears.

 

also the firing order on the opti is the same right 5371 and 4682