94/96 lt1 engine/ecm compatibility...

[V]

I have 2 cars, Car A is a project, Car B is for parts.

Car A:
96 LT1, Low mileage, great shape.
Currently has stock 96 ecm and stand alone wiring harness and does start/run
'89 700R4 transmission(no TCC wiring/setup)

Car B:(parts)
94 LT1, higher mileage, unknown condition.
stock 94 wiring harness and 94 ecm with pcm4less tune
4L60e(1994 correct) 4k miles on rebuild

Obviously the 700r4 in Car A isnt going to work properly as it sits and the stand alone wiring has no provisions for a transmission. It is just connected to the engine.

My idea is to swap out the '89 700r4 with the '94 4L60e.
Then use the entire wiring(engine & chassis)from Car B to REwire car A.(would be very simple considering the stage the car is at)
After the wiring is in, I could just plug in the '94 ecm to control the trans properly.

My question is... Will a'94 ecm and wiring harness PROPERLY run a '96 LT1?

Car A is historic so OBD/emission issues aren't a concern.Also, all AIR and stuff have been eliminated from the '96 LT1.

I could only find one issue mentioned being a different frequency of the knock sensor, and that would be resolved by just installing a new '94 knock sensor. Is it really that simple?

[LTb1ow]

Yea, as you pointed out knock sensor is different, and you would just need to leave the CPS unplugged. (I would sell the 96 timing cover and swap the 94 on, the 96 is worth a decent amount) Otherwise yea it should all be good to go, the 94 may have the oil pressure sender on the side of the block vs behind the intake like the 96 but thats easy.

Now, wiring wise, may be difficult. The issue lies in your data serial connection, I am not sure how complete your 96 standalone was, but are you gonna throw the whole 94 harness, engine side and car side into the vette? If so, you should be good, but if you mix and match the 94/96 you may need to rewire a few things.

[sweetbmxrider]

Yeah knock sensor and you just leave the crank position sensor unplugged. There are a couple small differences here and there but you have what you need to make it work. Like the coil plug is different iirc. You may have some issues with gauges/diagnostic test port that again, having both cars you can work around.

[V]

the stand alone will be completely removed and i would be using the entire 94 harness, engine and chassis sides. Even the 94 fuse box and gauges, everything.

[sweetbmxrider]

Yeah then you'll just have to switch knock sensors. The cps can be left unplugged. You could sell the timing cover etc but then you won't have a vented oem opti.

[LTb1ow]

Originally Posted by sweetbmxrider

Yeah then you'll just have to switch knock sensors. The cps can be left unplugged. You could sell the timing cover etc but then you won't have a vented oem opti.

Uh, what?

Leave the 96 opti, swap on a 94 cover. Vented opti, and you could make ~150

[sweetbmxrider]

Originally Posted by LTb1ow

Uh, what?

Leave the 96 opti, swap on a 94 cover. Vented opti, and you could make ~150

[AWARE]

92-94 Fbody



95 Fbody



96-97 Fbody



[/AWARE]

Just use the 94 cover with the 96 opti they said. Make ~$150 they said.

[V]

I wasn't planning on pulling the cover anyway lol. The '96 motor is too low mileage to open anything up if I don't need to. It's an iron headed LT1 too, but no point in changing heads since I'm just building a nice drive/cruiser.

I will be selling the 96 stand alone harness and 96 ecm though. Some where i still have the stock b-body '96 harness too.