A buddy is converting from the 8747 ECM to the 7060 PCM.

His speedometer reads correctly, but 7060 indicates a vehicle speed of 0.

He repinned the original 8747 connectors to the 7060 configuration, using vehicle diagrams.

Could it be that the 7060 requires a different VSS signal?

Could using a VSS from a vehicle that uses a 7060 correct the problem?

 

The 7060 is a PCM and uses a very different VSS signal. It needs the extra resolution for the transmission controls. As I recall it's 35 or 37 pulses per driveshaft revolution.

It's an excellent pcm, I have one in my truck, and like it.

There was some popularity with it with the 454SS Pickup guys so they might have a work around for the VSS..

 

Here's some related code I found, maybe you can sort thru this and get it to understand the optical setup you have.
HTH



;--------------------------------------------------
**************************
* SPEED SENSOR CAL VAL'S
**************************
L9021: FCB 0 ; 0 SEC BETWEEN DRP'S, (NOT USED IN PCM)
L9022 FDB $0000 ; PLS/REV, (NOT USED IN PCM)
; N * 8182/15
; N * 546.133
;
L9024: FCB 252 ; ENG SPD FILT TIME CONST
L9025: FCB 2 ; __ SEC MAX BETWEEN XMISSION & INPUT PULSES
9026: FDB 16930 ; 68.78PLS/REV INPUT SPD CALL
; RANGES 18 TH 38
; N * 8182/15
; N * 546.133
L9028: FCB 252 ; INPUT SPD FILT TIME CONST
L9029: FDB 43691 ; 0.749:1, OVERDIRVE RATIO
; 0.5 to 2:1, 2^15/RATIO
L902B: FCB 252 ; 6.3 SEC'S, XMISH SPD IN FILT TIME CONST
L902C: FCB 2 ; 0.050 SEC MAX PERIOD OF XMISH OUT PULSES
L902D: FDB 43691 ; 40 PLS/REV OUTPUS SHAFT
; CAL VAL = FACTOR * 2^14/15
; FACTOR * 16384/15
FACTOR * 1092.266
L902F: FCB 255 ; 6.38 SEC'S, XMISH OUT FILT TIME CONST
L9030 FCD 47161 ; 46.055:, SCAN TOOL SPEED VALUE AT
DRIVELINE 60 REV/MILE
VAL = RATIO * 2^10
L9032: FCB 252 ; Vss FILTER TIME CONST

 

Yeah, there's some popularity with it. I'm one of those guys!

I was waiting for someone to work out the bugs in the conversion before I did it.

Doesn't the 7060 use a DRAC?

Thanks for the info. Anything else you can think of will be greatly appreciated!


Bill

 

Not according to Alldata.
That'd just be tooo EZ.

 

To bring this post back from the dead.... I'd like to do the swap the opposite way. A 7060 PCM to a 7747 ECM.

Reason being; Can't seem to find the proper definition file to read the BDPN bin from the current computer. It's a G300 van that had Vortec heads and slightly better cam put in and needs some tuning. I have worked with the 7747 ECM plenty and can tune that no problem. I have the ECM, wiring, sensors if need be.

The only thing I don't know is the VSS and trans controls.

Any insight?

Thanks
-Paul

 

Welll... The VSS is easy as the DRAC has a 2K PPM output for the '7747. However, you still need something to run the 'E' trans, as the '7747 won't do that.

Can piggyback the '7747 with the '7060. Leave the '7060 to run the trans and let the '7747 run the engine. This setup is common with EBL users.

RBob.

 

the 7060 uses mask $85. what software are you using?