DRAC/VSSB Questions...

**1project2many** · 01-03-2019

If you'd like to try and adjust your DRAC, here is the information to DIY:
http://gearhead-efi.com/gearhead-efi/doc/DRAC2.pdf

**In-Tech** · 03-05-2020

Hi Guys,
Really good info in this thread. I have never had to mess with any DRAC stuff and I've got a project to dive into. It's a 56 ford with a '94 Whipplecharged 7427 but has a 700r4 behind it. Of course the aftermarket digital dash speedo doesn't work as well as no speed to the 7427. I think it has a cable drive now. I've heard of cable drive adaptors for the vss output but don't know anything about them. Is that a standard 40 ppr item or are they all different? Should I or is it possible to put the output stuff off of a 4l60e onto the output shaft of the 700r4? Does the 7427 just need 40ppr signal or does it need the 2000 ppm signal or both? I'll check if the aftermarket electronic speedo can use either signal or a specific. Maybe I don't need a drac module???
Sorry guys, this is just basic stuff to some of you that have been through it. I'm trying to wrap my head around it all

-Carl

**In-Tech** · 03-06-2020

Hello,
This has a Dakota digital dash. There is a 2 wire speed sensor coming out of the t700, appears to be part of the Dakota kit and hooks to the Dakota dash. From what I read, there is a 2000ppm wire coming out of the Dakota dash. Is this as simple as Programming the Dakota dash to get the speedo correct then hook their 2000ppm wire to pin F13 of the 7427 blue connector and no need for drac/vssb?

**EDZIP** · 03-07-2020

If you need switches I have extras...

**In-Tech** · 03-07-2020

Originally Posted by EDZIP

If you need switches I have extras...

Yeah you do. :) I would like to put a couple vssb's on the shelf and do the dip conversion too. Post here or pm me a price on 2 with the pigtails. Thanks

**PlayingWithTBI** · 03-07-2020

Originally Posted by In-Tech

Hello,
This has a Dakota digital dash. There is a 2 wire speed sensor coming out of the t700, appears to be part of the Dakota kit and hooks to the Dakota dash. From what I read, there is a 2000ppm wire coming out of the Dakota dash. Is this as simple as Programming the Dakota dash to get the speedo correct then hook their 2000ppm wire to pin F13 of the 7427 blue connector and no need for drac/vssb?

I have a Dakota Digital dash in my 88 C1500 with the 700r4 trans which already has the 2000PPM encoder but my ECM (7747) still got the original pulses from the VSSB adapter on the back of my instrument cluster so, when I changed the rear end to 4.11 from 3.42 my ECM was off. I could not confirm whether the out put from the DD was a pass through or it converted pulses once the DD speedo was calibrated. Before I pursued it further I switched to the EBL Flash2 which has the ability to calibrate it internally. Maybe if you called tech support, they could help?

**In-Tech** · 03-07-2020

Originally Posted by PlayingWithTBI

I have a Dakota Digital dash in my 88 C1500 with the 700r4 trans which already has the 2000PPM encoder but my ECM (7747) still got the original pulses from the VSSB adapter on the back of my instrument cluster so, when I changed the rear end to 4.11 from 3.42 my ECM was off. I could not confirm whether the out put from the DD was a pass through or it converted pulses once the DD speedo was calibrated. Before I pursued it further I switched to the EBL Flash2 which has the ability to calibrate it internally. Maybe if you called tech support, they could help?

Thanks Bro, I will contact them next week when I am back on the project, good info. The customer just texted me a pic of what he removed when he put the speed sensor in. It was the speedo gear

so no reluctor. Should I just put a reluctor on the shaft from a ~'94 4L60E? Are the reluctors the same in the early T700R4 TBI 7747 apps? Or have him get one of those speedo cable adaptors and put the gear back in? (I might have one in stock)

Thanks again, guys, for all the help :)
-Carl

I'm not going to edit my post but I want to apologize for laughing above

about the removal of the speedo gear drive. Heck, we all had to start learning somewhere and even though I've been doing EFI tuning since the early 90's, I still learn something new almost every day.

**PlayingWithTBI** · 03-07-2020

When I got my stage 2 700r4 it didn't come with any gear on the tail shaft (they rarely do), I ordered one from Amazon, IIRC, and used my OE reluctor. You should be able to get it from Amazon too along with the gear. It's real easy to remove the tail housing, pay attention where the gear is, pull it off, heat up the replacement gear in the oven or boiling water, slide it on to the same position as before, re-install the housing and bolt in the reluctor. FYI, if you jack up the back of the pickup, you won't lose hardly any ATF, you'll lose more when you pull the drive line. Another way would be to use a GPS.

https://www.dakotadigital.com/index....rod/prd837.htm

**In-Tech** · 03-07-2020

Thanks for the link. I won't need that on this project but I have a Ford Coyote in a '40 Ford to work on soon and the customer wants the cruise control to work. We're not sure what computer we will use yet but that device might come in handy.

-Carl