I transplanted a 454 running with a 7747 into my Blazer with a 700r4. A 7747 is for a manuel tranny right? I was told this is why the park/neutral and TCC do not funtion(acording to scanner. Is this true?

Can i just pickup a chip for any TBI with an auto? Or does it have to be from a 454 with an auto? Thanks


Charlo

 

You want to match the chip to the appication as closely as possible!.

The 7747 was used in both manual and auto applications.

 

Hmm, the '747 will run either a manual or an auto tranny. Sounds like you have an auto, so best bet is to start with an auto bin.

As for the park/neut scanner info did you hook up the park/neut switch? May need to check it. I isn't too important in reality. Left open is same as a in-drive status.

The TCC is is dual purposed with the shift light. A auto bin wil control the TCC, a manual bin will control a shift light. They both use the same status bit internally.

RBob.

 

So I need a bin from a 454 with 700r4? Not sure that was a combo from gm. Would a 454 with th400 work(no TCC)?

The one I have is from a stick. I think that is why park/neutral does not work but i will double check my wiring.
Thanks guys

Charlo

 

You may need to graft the TCC tables in from a bin that used the 700R4. This is just the data as the tables already exist. On the th400 equip'd '747 vehicles the TCC output was used as the trans kickdown. So you don't want to that bin w/o changing the TCC tables.

Start with a 454 auto bin and setup the TCC tables and go from there.

RBob.

 

You the manBob! Thanks for the info.


Charlo

 

454 auto trans bins are ACLU, ANTY, ATPX, AZFT.
AZFT was the latest revision, it is available here:
ftp://ftp.diy-efi.org/pub/gmecm/bin_...9/azft9503.bin

Ben.

 

I'm dealing with this soon too, putting a 700R4 behind a 454. If you put in the TCC tables, will that make it re-purpose the signal to run the TCC instead of the kickdown? Or is there somewhere else in the code that needs to be tweaked?

 

My understanding is that it is just the TCC calibration values. The kickdown and the TCC un-lock is basically the same functionality.

RBob.

 

OK. I think I can handle that. I have a VSS now, so when I get the tranny in, I'll see what happens.

Thanks,