i was trying to figure out which opti i was gona go with an gm, one from advanced auto, or an msd.


and as i was siting there thinking about it i dont understand why they went with the opti. they were obviously capable of coil packs because the v6s were using them. so why did they chose to use the opti?

 

gm opti for the win!


the way i see it people give the opti a bad wrap,personally i think it is a very powerful unit
and like everything else it has its limitations.....
New gm opti and the LTCC or delteq..

 

The opti has a VERY bad rep. But it was actually top of the line when it came out in 92. Its high resolution cam positioning made engine timing extremely accurate. If the opti were to stay dry all the time, it would be a force to be reckoned with. But because of its location, it gets oil and moisture inside very easily, which obviously destroys it.

So in theory, GM knew what they were doing when they built the thing. We just get stuck with all its shortcomings. And as crappy as the opti can seem, it still kicks all our asses every time, and we keep buying them . Touche, GM.

 

Unless someone here was in on the LT1 engine design, I don't think you will get a good answer.

 

well, also look at where a GM dist. is normally at on a v8....in the back behind the intake. Oh, look where theres NOT any room in an fbody...

 

i just wonder why some engineer at GM did not make a small aluminum pan that mounts under the waterpump that channels water away from the opti incase of a waterpump failure

 

sounds like a GREAT idea...i will try to fab one up when i install my new waterpump

 

its actually down in the front to reduce deflection of the distributor shaft when making a 90 degree turn

 

The 360 pulses from the timing wheel provide a much more accurate spark timing, resulting in reduced spark scatter. This reduces emissions and improves fuel mileage. GM did a Society of Automotive Engineers (SAE) paper on the design, citing the reduced spark scatter as the primary advantage of the design.

The design was not developed by GM though. It was originated by Chrysler/Mitsubishi, and used in their 3L V6 engine in the late 80's. Diamond/Star simply had the common sense to locate the distributor in a more conventional location, and not under the water pump. Hence, the Mitsubishi name on the optical sensor.

 

Because it is possibly the most advanced mechanical distributor ever made:
http://www.gmhightechperformance.com...ing/index.html

When its working properly it has huge gains over dated designs of the past.

 

It is a very good Idea and if it extends down around the crank to the front oil pan studs it would also decrease moisture from driving through puddles. I have a lt sitting on the engine stand now and will see how problematic it is. It has to cover the opti but also has to be detachable easily. Then I can wash my motor

 

i thought about making one for my driver but i have not had the extra time.
figure a thin peice of aluminum 18guage with mounts that utilize the lower bolts on the waterpump.

 

The location of it makes it a pain though. Expessialy for plug wire routing. I like the coil pack idea alot better then the optispark.

 

If you want to keep a dry opti and have less headaches with it take it apart and seal it with some RTV. Seems to be a suggestion even from dealers themselves. I have a friend that works for the GM dealer here and he says he always takes this precaution because he sees how expensive they are and doesn't want the customer to come back and blame him.

 

I did that when I replaced my opti a couple years ago. Haven't had any problems with it so far. The designers should have atleast created a rubber boot to cover the opti. Like Ford did with their regular top mounted distributors.