TBI ignition modules same?

[Irish1941]

My '89 K5 threw a code 42 other day so I figured it was time for a new module. Idle was acting up surging so I was expecting this.

Anyway, go to Rockauto and they show 2 Delco modules:
19179578
19294247
Funny thing is the last number, 19294247, for 4WD applications and is about $40 more.
Sounded weird to me because I thought all ICM were the same so I search under 1992 C1500 and 4WD number came up for 2WD truck...what the???
Try '91 Sub, same thing.

Hit GM Parts Giant and it threw back two completely different numbers again!
10482820
10482827 for 350 in K series.

I was never offered any choices with ICM in years prior when replacing them.
They would ask the year, I'd tell them and they hand me a module.
Anybody shed some light on this? Is there REALLY a difference?

 

[eagle mark]

They all work but where is your timing really set to? If you choose an aftermarket over AC Delco then it's even worse because of spark latency settings in chip/bin don't match module.

The 048 module, it held steady timing until about 3800 RPM where it retarded 4 degrees. Then by 5000 RPM the retard had increased to 6 degrees.

The 369 module, it held steady timing until about 3200 where it gained 2 degrees of advance. This held steady to 5000 RPM, which is the highest RPM it was checked at.

 

[Irish1941]

Ah...I see.
Now we're getting into something I don't know much about.
Truck never sees other side of 3K and currently timing is 2* advanced.
With 7747 ECM and the 369 will tables match?
I needed to get on the road again so I have a 369 on it's way.

I don't know if it's a Delco in there right now. Never looked and never changed it.
All of my spare TBI distributors all had made in Hong Kong modules so I wasn't putting that in.

Anyway, I used to hit the wall at 2500 on an incline. Foot to the floor, nothing. It would shift down out of OD fine but just had no more to give in third. Temp would climb up too.
Threw on a MSD coil, better cap, advanced 2* and Delcos gapped @ .45 made a big difference. Hit the same hill but now it pulls hard to 2700 in 3rd but still runs out of steam. Temp stay downs now too.

I was over on thirdgen.org but they are talking about losing spark over 5K and only way my truck would see 5,000rpm is off a cliff with a brick on the pedal.

Anything you can share would be most welcome.
I haven't used WinALDL yet but maybe I should but then again it'd be all Greek to me...
Thanks for the reply
**Update**
Pulled out the old module. It was a 369, made in Singapore, and yellow dot was visable. I think the dot appears if it's been over heated or so I have read. No heat sink on it.
Covered the bottom in heat sink and slapped in the new Made in USA Delco module and the surge in my idle was gone. Ran better than it ever has since I had it.