Need help with 16176261 -> 1227730 pinouts

[LeeT1]

Hi all
I have a 16176261 ecm installed on my 3100, which lives in a '67 MGB. Not sure of the original source. The only possibility I can find is 1994–96 Corsica. I also have a 1227730 that I would like to swap in. Can anybody point me to pinouts for these 2, so that I can make the swap? Also, what is the difference between these two? Are they fully interchangeable? The 1227730 is well documented, hence the desire to make the change.
This engine is built from LH0 heads and LG6 block with a pretty aggressive cam. It runs good, but not great. I'm getting the car sorted out, and it's time to learn the ecm programming and start working on the tune. Ultimately, the 3100 will be replaced with a 3900, but one step at a time.

Any and all help is appreciated.
Thanx
Lee

[Superdave]

Your best bet would be to get a complete OBD1 engine harness for the '7730 and toss the OBD1.5 harness. early 90's J-bodies have one that works well (that's what i used in my Camaro swap).

I'm curious though, why did you decide to use LHO heads on a LG6?

[LeeT1]

Thanks for the reply, Superdave. You have cleared this up quite a bit for me. So the 16176261 is OBD1.5, correct?

There isn't much of the original harness left, since it no longer resides in it's original home. It has been cut and re-wrapped to fit, sorta... Only what is necessary to run the engine is there. No EGT. Also, no PS, or AC. Check me, but I think the sensor list is TPS, IAT, CTS, MAP, CS, NBO2. Since this engine lives in a MGB, there are no accessories, and no smog concerns (not even in Calif... ), just engine control. This is the reason I am (currently) leaning towards moving pins in the connector blocks. Currently have a real rats nest around the computer. But the wiring on the engine is pretty clean. I will also be looking into pins and a crimp tool. I think it is the only way I will ever get a neat engine compartment. Both computers have Sinister Performance chip carriers in them. Not sure if the 7730 has ever been in. Am I correct that the sensors currently installed will work with the 7730? This is a study like mad and learn as I go type of operation.

I bought the car from the second owner. He bought it with the engine installed, and got it running. I am going to make it right. So, I didn't build the engine. I am sure about the LH0 heads. Not sure about the block. It may be a LH0 block fit with LG6 pistons. Sketchy info from previous owner. Can you point me to info that will help me verify this? I haven't done a compression check yet, but the compression is high. Marginal on 91 octane gas. After loosing the fuel pump, which was sucking on the original tank from about 2 feet away, (or trying to) I have swapped in an aluminum gas tank with internal fuel pump. So the fuel system is now good. I am now going after the ECM. I also pulled the heads for a look see, and to get to know this engine. This is my first 60V6. Everything checked out OK, so I cleaned the chambers and piston tops and have the heads back on. I have another thread in the Pushrod Maintenance forum looking to verify that the LIM gasket set that I have is the correct one. So now is a good time to re-wire this thing if I need to.

This will be an ongoing project. I am building this car into a track toy / street car. A full suspension build is in the works. Also, I am looking for a 3900, but I want to sort out what I have first. And that means getting the 7730 in and the tools to tune it.


Thanks again for the help. I really appreciate any help you can provide. I have a lot to learn.
Thanx
Lee

[Superdave]

now that i've thought about it, the 16176261 is probably a later version of the '7730 or a water tight version, can you post up a picture of it? It's gotta be a OBD1 ECM in which case there may be no need to change to a '7730 or a harness change.

[robertisaar]

"Both computers have Sinister Performance chip carriers in them."

doesn't sound like a 1.5PCM....

and i googled the ECM P/N but didn't come up with anything. also in for pics.

[LeeT1]

Here it is, Dave. After getting wiring out of the way, a closer inspection suggests that I grabbed the wrong number. I do believe this is a 1227730. So one problem solved.



Saturday I visited my favorite racer parts yard, and there set a just received 2000 Malibo, with a very clean LG8. I see a new top end in my near future.
Also, where can I find diagrams of the motor mount attach points in the various blocks? it is my understanding GM changed these a lot. Just trying to figure out what may be compatible with my engine mounts.

Thanx again
Lee

[Superdave]

Yep, that's a '7730.

the LG8 and LA1 (3100 and 3400 generation 3) have the same mount pattern, the older Gen2's (LHO) have similar on the back side (passenger) but the front(drivers) is quite a bit different.

The 3500 LX9 (Gen 3) has a slightly different pattern on the back side and the front is also similar to a 3400 other than missing the 2 bottom bosses above the oil pan. Not sure on the gen 4 3900, i'm guessing they changed it again. It shouldn't be too hard to modify your mounts for whatever engine you choose.