VSS from Speedo to ECM or DRAC/VSSB 4L60E

[Nasty-Z]

On my S10 pickup '7427 conversion , I used the VSS behind the dash cluster and inputed it to the '7427 via F13 , Everything worked fine . it is a stick box however.

So I guess my question , is do I have to run a VSSB/DRAC to control a 4L60E ? Or will the input at F13 be OK for a speed siginal for the 4L60E ?

Sorry for the thread Jack Mark :)

TOM

[EagleMark]

We're used to hijacked threads around here, but that's a good question and I think I'm going to make a topic out of it... It would boil down to what signal comes from VSS behind speedo, most all I know of went to DRAC/VSSB

[Nasty-Z]

Cool , Thanks Mark

The output from the cluster mount optical VSS is 2000PPM that I inputed into F13 , it is what the PCM wanted to see there so all works well.

I just have to wonder if all of the '60e controls will work with just that input ....

TOM

[Six_Shooter]

You must use the VSS in the tranny through a DRAC, for tranny control. The 40 PPR pulse is what is needed for proper tranny function. I don't recall which pin that is on, but using only the F13 pin will not control the tranny.

[Nasty-Z]

You must use the VSS in the tranny through a DRAC, for tranny control. The 40 PPR pulse is what is needed for proper tranny function. I don't recall which pin that is on, but using only the F13 pin will not control the tranny.

Damnit :(

Alas , I cannot use the factory speed sensor ...... Oh well :(

TOM

[Six_Shooter]

Why not? The 4L60E will have the VSS already installed.

[Nasty-Z]

I'm mating a 4wd 4L60E to a 205/203 doubler setup in my '84 S10 Blazer . The 205 only has a cable speedo provision.

I need the cable output on the 205 for my speedo , guess I could run an aftermarket VSS and wire in a DRAC/VSSB though .....

If I can be dumb , why did I only need the 2000 ppm input on my 92 TBI truck with a 5 speed , is there another input to the PCM that it needs to see to control an electronic trans ?

TOM

[EagleMark]

I think you missed what Six Shooter was telling you. 4L60E has a VSS in it, use it to DRAC/VSSB then to transmission. You should get your VSSB from same PCM/vehicle.

DRAC/VSSB does a few things, major issue is taking the AC or DC sine wave and buffering to square wave, some ECM/PCM do this, others do not. It also adjusts signal to speedometer, cruise control and Anti Lock brakes. I know the 1227747 can not make these adjustments for gear change and has to be done in DRAC, I think that is the same with 16197427 PCM type. Where as my LT1 I can adjust bin for these changes and know of no DRAC/VSSB in car so it must be part of newer PCM.

Technical I don't know why 4L80E wiring diagram shows VSS is wired into PCM with no DRAC/VSSB then wires to transmission. In $OE which is designed for 4L80E there is a bitmask to check/unchecked for "Output Speed Not from DRAC" There is no option in $OD designed for 4l60E.

Which brings up another point I had made about 16197427 being latest of that family of PCM being able to handle everything in one PCM. I have a 16197427 which is thought to or originally came with 4L60E and $OD but mine came with $OE and 4l80E bin.

[Nasty-Z]

On a 4X4 4L60E there is no speed sensor provision , it is on the transfer case . On the t case setup I am using a 40 tooth ring and VSS is not an option.

In $0D on a manual transmission application , the factory optical (2000 ppm) cluster mount VSS can be inputed to the '7427 on pin F13 , works fine , I run it on 2 of my trucks as of now.

TOM

[Six_Shooter]

E tranny control requires an additional input, hensevtye need to use the 40 tooth tone ring and DRAC for tranny control.

[Nasty-Z]

E tranny control requires an additional input, hensevtye need to use the 40 tooth tone ring and DRAC for tranny control.

Thank you

TOM

[EagleMark]

Poof! Done! Jaqs that run 40 tooth bolt on VSS. Although for an off roader I'd put it up on transfer case end...

http://www.gearhead-efi.com/Fuel-Injection/attachment.php?attachmentid=1616&stc=1&d=1328986076

[dyeager535]

why is the 40 tooth tone ring for 205 not an option? '90-91 one tons used them, I have one installed in mine. Wired to DRAC, feeds the electric speedo and ECM.

Granted, fairly rare pieces, but they are out there. Far simpler to use than the aftermarket options out there, although the bolt on Mark showed is pretty simple, still something to get a branch or rock thrown into.

[Nasty-Z]

why is the 40 tooth tone ring for 205 not an option? '90-91 one tons used them, I have one installed in mine. Wired to DRAC, feeds the electric speedo and ECM.

Granted, fairly rare pieces, but they are out there. Far simpler to use than the aftermarket options out there, although the bolt on Mark showed is pretty simple, still something to get a branch or rock thrown into.

I have a few of those also , and could use it if need be. At this point I still need the cable for the speedo in the dash , and I cannot swap to a later dash as the 83-84 were specific and not interchangable to the later years.....

Might just make it simple and go to aftermarket gauges ....

Thanks for the thought though .

TOM

[woody80z28]

A slight hi-jack if I may...

How do I calibrate my 7427/$0D/4l60e speedometer after a tire size change? I swapped in a 5spd and checked the manual trans box in the BIN, so is there a place to adjust the speedo in the BIN, or is it done by the DRAC even though it's not controlling an auto trans?

[EagleMark]

DRAC on C3 ECM and VSSB on C4 PCM.

Start a thread, good topic although we haave talked about it I don't think we ever walked through the process. I think I have all the information needed to do this and can tell you why there is some serious issues with writeups on internet with use of DIP switches...

[93V8S10]

some serious issues with writeups on internet with use of DIP switches...
If your talking about the on-line calculator one I think your talking about, I've got a correction list around here somewhere.

[EagleMark]

Actually we have GM docs of correct locations for jumpers and speeds etc... what I was referring to was using a dip switch recommended does not work, it burns up, I have tried to find one that will handle current but unsuccessful.

[93V8S10]

Mine has been working fine with dip switch now for about 5 years.

I'll stop now, until we get a new thread going.

[EagleMark]

See you proved me wrong. Where did you get the dip switch? I tried three differant brands, they all fried?

No need to stop now, I can split the thread.

[93V8S10]

Got it from a local electronics suppler, came two to a package. I should have the other one around here somewhere, I'll let you know the brand when I find it. Also, mine is the small DRAC used with S/T, not the larger one used with full size. Don't know if that matters, but might make a difference.

[EagleMark]

Wire size on DRAC (what you use) and VSSB are same size. I have burned up dip switches on both. So really interested in one you have. I ended up doing the calculations and soldering in wire/wires in jumpers.

[droptopstng]

Hey Mark If i may say this a company called classic instruments makes a piece to screw on where the cable goes that produces correct output for those swapping from mech to ele speedos....we have had 8 or 10 customers bring them to us to install in the past few years I would call them.....this was meant for the op of this btw.....and about the dip switch thing I need to know because my bosses truck I just soldered in jumpers but it took an hour or so so some dips would have been nice.We got his within 3 percent I think, we did it like a year ago.

[93V8S10]

Fount it!

The parts are made by Jim-Pak Electronic Components, located in Belmont, CA 94002. I solder the 16MLPJP 16 pin low profile machine tooled IC socket to the board then plugged in a 206-8 8 position DIP switch (both with two legs removed).