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hi im doing a whole write up since im about to jump into this. and will be sharing once everything works with the community.
I will be using the cheap way no coil on plug.... just wondering about the pin outs or to have someone to compare with.
yeah I know about the horsepowertube stuff.. but it seems confusing in some areas why he used some joint pins when there are specific ones on the 411 for them, plus im doing the 4l60e not a t56...
 

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For your swap, I recommend going to the gearheadefi forum. They specialize in pcm problems & info. I feel you'll have a much better chance of getting your questions answered there.

Our pcm specialists rarely visit ls1lt1.com anymore. It good to see you back, most of the older members have sold their 4th gens and moved on to newer cars.
 

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For your swap, I recommend going to the gearheadefi forum. They specialize in pcm problems & info. I feel you'll have a much better chance of getting your questions answered there.

Our pcm specialists rarely visit ls1lt1.com anymore. It good to see you back, most of the older members have sold their 4th gens and moved on to newer cars.
thank you! and yes ive had the lt for 14 years now. and still loving it.. I wont get rid of it...
I dont really think it should be a specialist kinda deal, I am very familiarized with this pcms and they are quite simple, plus this would be a comparison only kinda thing... still If this works I will be sharing,, I bet a lot of people would love to get rid of the opti spending couple bucks on a pcm and some bench work and open up HPtuners for the lt1 engine tuning capabilities... plus no more opti trouble :)
 

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Your offer to do a write up is a good one. Keep us posted. I've never worked with that pcm, so this will be a learning experience for me.
 

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Your offer to do a write up is a good one. Keep us posted. I've never worked with that pcm, so this will be a learning experience for me.
Definitely, i have everything done, from the c1 c2 c3 c4 lt1 pins, to the c1 blue and c2 red 411 pcm.

The 411 is a way faster pcm, its been used in many gm cars and trucks.
Hp tuners even has an autotune option to fine tune ve's on the go.

So if you are familiarized with hp tuners it will be a sweet upgrade

As mentioned, this guy on his fb page horsepowertube he made it, but it was on a t56 firebird... Look for it. Its very cheap, just a pcm from a junkyard and 100 bucks on credits if you have hpt already and/or if desired basically any ls tuner can work the lt1 easily.

Ill definitely try it on my car first, just to know what im sharing works. I just gotta find some time to do it.
 

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Hiya,
I’m also following this thread.

What are you using for crank position input if the opti is not being used?
I’ve seen conversions using I think the 24? Tooth reluctor.

Mitch
 

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Hiya,
I’m also following this thread.



What are you using for crank position input if the opti is not being used?
I’ve seen conversions using I think the 24? Tooth reluctor.

Mitch

96 97 lt1 use a 4x crank sensor, previous non vented optis dont use this. So if 95 or lower you need the 96/97 front cover, 4x reluctor wheel, and hub.
The link between ls1 coil on plug is the vortec 5.3 with the distributor on the back.
This vortec uses a 4x crank and a cam sensor in the distributor. If you unplug the cam sensor it still runs, but instead of having a sequential fuel injection runs in batch fire injection.
Every single sensor in the vortec is the same as in the lt1, and its single coil fire with the same electronic control module.
The opti spark has two segments. The optical part (which is the one that fails) and the front part which acts as a rotor and cap.
So the theory behind this, is that you basically get rid of the optical part. And still use the opti as a rotor and cap for firing order.
 
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Hi!
I just completed this very same conversion on my ‘96 Trans Am WS6.
And you’re right about Kyle’s (“Horsepowertubes”) pinouts, If he would clean up the sheets he posted and make the instructions more clear, they would help explain things better.
he stated using the 5 volt reference wires merged together for some sensors. He listed all the factory LT1 connectors C-1, C-2, C-3,C-4 and put notes on the pinout sheets, I believe it would make things clearer to just place the notes on separate sheets. The unused pins with them being “Lined out” just adds to the confusion. If you are deleting emissions wiring, if those wires were “High lighted” in a specific color Like LT1swap.com (Brandon) does on his pinout sheets.
Since the 2001 Chevy Express Van with the 350 Vortec engine has a crankshaft position sensor and Camshaft position sensor, it’s got the same firing order as the LT1, same ignition coil And module. You need to start with a base 2001 Express Van tune for an L31.

I have all my emissions turned off, the cam sensor is set to fail for “Batch Fire” mode (the cam sensor DTC and MIL light are turned off)

my first start was pretty rough, (when I first started “re-pinning” my harness, I replaced the “MAP” sensor connector, because the lock tap had broken off) well , I un-pinned the original connector, and I didn't mark The original positions of the 5v ref. And ground wires, which were swapped,
Made the engine run awful. So I started checking my sensor voltages and checked the harness from the PCM to the connector for continuity, they all checked out fine ( because the color codes of the wires and the PCM connector numbers were spot on, that threw me off, I kept getting weird readings from my MAP sensor, the 5volt reference signal volts were now reading 1.75volts. I checked the Schematics, and looked at some photos of other LT1 engines and noticed I had the two wires mixed up.
Once That was fixed, the map sensor read just like the vacuum/voltage chart said. The engine idles much better, isn't running “Pig Rich” and Now I can move onto tuning it better.

I am Using “LS Droid” with the “OBDLink MX+” to read and flash my 0411 PCM. I can also Data log using the OBDLink MX+ As it’s a bluetooth elm dongle.

As of right now, I have to replace one of the two O2 sensors (Bank two is not reading correctly and I just replaced both with new Delco sensors)
That should make it run a little better.I’ve also got a “back fire” in my exhaust randomly, and on deceleration,
Probably due to the O2 sensor.

If anyone has any suggestions, or questions, please feel free to ask!
Have a good one!
Ben Smith
 
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