what is the dif from the 1228063, 1228746 and 1227747 ecms

is one beter than the other. are the wireing harnesses the same is one more tuner frendly.

 

The 1228746 is the car version of the 1227747, and as such it uses a IAT sensor. Plus the calibrations are somewhat different since one is for a car and the other a truck. The 1228063 as I recall is just an earlier verson of the 8746.

There all C3s, which are a real early series of GM EFI ecms.

 

would i gain any thing swaping out the 747 for one of the other 2

 

Depends upon the application. Both the '747 & '8746 have code that the other does not. The '8746 has a lean cruise mode (patch available for the '747), and has SA idle control. This provides a better idle. The '8746 also has some fueling control via an IAT.

The '747 has better AE control. Just right for heavier vehicles.

Both have a patch available to eliminate the forced knock test.

The '8746 has a patch to change the speed limiter to a rev limiter.

I am not familar enough with the '8063 to pro/con it.

RBob.

 

i have the 8746 and have heard that it has a slower baud rate when compared to other cars with different ECM's (speciffically cars with TPI). If i understand correctly then this means that it is harder to tune with this ECM. Would i gain anything by switching to a faster ECM? (gain meaning makeing tuning easier/quicker/more efficient, not HP). If so, which ECM(s)? Im getting the prominator soon and this info would be great.

-chuck

 

Let me add one to the question : 1228062 It's what my S-10 has in it. I know the pinout is nearly identical (if not the same as) with a 747.

Mainly just curious!

 

I'll ask one too...
Where are these patches you are talking about? That rev limiter thing would be great.

 

In the stickies above look for the 'patch method demo' thread. Two nice patches for the '8746 in there. . .

RBob.