Redliner

You know the speedo calibration box from Dakota digital
Before I go hacking into the computer harness, can anyone tell me what wires (color) I need to use. Also, I feel that I am going brain dead could you also tell me which wire is hot in run so I can give it a convenient power source.

Thanks a million.

Redliner

TTT

JoelOl75

I too wish for better info on the SGI-5 (TTT) a good place to hack into for the constant power would be the cigarette lighter. But I've been driving around with a dead speedo with the damn thing hooked up like so:

Yellow wore from VSS hooked to sig in, purple to ground on both sides of the harness , and a combo of DIP switch settings I got from the manual, I think I used OUT 4 (TPI), with the setting to start with in the manual with nothing, not a budge of the needle.... I will mess with it later..

r90camarors

I spliced into the wires running to the vss near the tranny. If I remember right, it is alternating current and doesn't matter which one goes to the "IN" on the box. I'm going to work on my car tonight, so I can check for sure, but I think I used "OUT 4". I know the manual is wrong in its suggestion for TBI cars. I used my Cigarette lighter as a power source. Also, remember to wind (spiral) the signal wire and ground wire, or else your speedo will get crazy sometimes.
I have 3.73s as well, so if you want I can get you the calibration code for it as well.

BOTTLEDZ28

iTrader: (9)

r90camarors, can you getme your calibration codes? I have the t6 with 3.73 and havent gotten a chance to mess with fine tuning it. kid takes up most of the day now but its ok.

r90camarors

Yeah, not a problem. I should be able to get them today. I just got the engine running yesterday, wow is a ll I can say. She's one mean sounding 383

1bad91Z

iTrader: (1)

Yea, I have had mine in the car for 6 months now and I haven't had a damn speedo since! I wired it up exactly like the manual showed and the only output I got to move the needle was output 1 and made the speedo very eratic. Any hints would be appreciated!

Mike (1bad91Z)

r90camarors

I'm sorry I haven't gotten the code yet, had to bring the car in for some exhaust work Hopefully later this after noon I'll be able to get them

1bad91Z

iTrader: (1)

The signal wire on the VSS goes to the input on the SGI and the other VSS wire gets grounded, right? Also what output # are you guys using?

1bad91Z

iTrader: (1)

Anyone????

Also, does the T-56 have a 40 pulse per DS revolution VSS or a 17 tooth per DS revolution VSS?

Has anyone got there SGI-5 to work correctly with a 1991 speedo (730 ECM)??????

Also the 2 wires coming from the T-56 VSS, is one a specific signal wire and the other a ground or are they not specific and you can ground either one?

Help is needed!

Thanks,
Mike

BOTTLEDZ28

iTrader: (9)

as far as I know, the 2 VSS wires are just signal wires and it dont matter which one is grounded. I have the purple one grounded. as for the t56 signal, I have no clue. I think its 40

1bad91Z

iTrader: (1)

BottledZr28 - what year is your car? What gears do you have? What output # did you use? And does your speedo read accurate or is it off a little?

Thanks,
Mike

1bad91Z

iTrader: (1)

I'm going to completely re-wire the SGI-5 conversion box to see if that helps.

My question for you guys is: Will turning off VSS diagnostics in the PROM have any effect on speedo working/not working, any effect on the purge solenoid on ECC canister, engine idle, and or air/fuel ratio?

I'm using tunercat with $8D.

I DO know that the VSS does effect all of the above listed, however due to the code caused from the no VSS signal from the SGI-5 box not wired or calibrated correctly, I ended up disabling VSS stuff in the PROM. Do I need to re-enable it?

Also, once the VSS signal reaches the speedo (if I can get the SGI-5 to work), will everything above mentioned still function properly with the VSS stuff in the PROM turned-off?


Thanks again for the continued help!

Mike

BOTTLEDZ28

iTrader: (9)

my car is a 1991 and I am using OUT 4. my speedo shows about 10 mph slower then actual speed. Ihave 3.73's.

1bad91Z

iTrader: (1)

BOTTLEDZr28 -

Does it matter what VSS wire gets plugged into the signal in port? If not, do you need to ground the wire NOT used for signal from the VSS or just leave it hanging? I put one VSS wire in the sig in and the other I plugged into the ground port on the SGI-5. Should I take that VSS wire out and ground it to the chassis instead?

Also, if you're 10mph off, will adjusting the switches correct it?



THanks again for the continued help!
Mike

91Z28-350

I haven't adjusted my speedo yet, meaning playing with the dip switches. I had run them in twisted pairs. So, VSS-A and VSS-B twisted up through the hole for the 700R4 shifter (with the existing grommet), and The yellow and purple wires from the wire harness, extended and twisted up through the hole too. Then I connected the purple and VSS-B to GROUND. The yellow went to OUT3 and VSS-A went to SIG-IN. Power came from Accessory power for the radio (not hot at all times, only when the key is switched).

I just need to set up the dip switches appropriately for the speedo. What I will do is go to a speed shop, throw it on a dyno and have the mphs gauged, then I will set the dip switches for the proper ratios. I do have the DIP switches set to OFF-OFF-ON-ON-ON-ON-ON-ON-ON-ON, as per the instructions.

Edit: per the Helm service manual, the purple wire on the wire harness (going to the 700R4s VSS connector) is ground. I twisted the wires due to the suggestion from Dakota Digital to twist the signals with ground to minimize signal degredation. I guess like a CAT-5 wire running in twisted pairs. Because the purple was ground and the twisted pair recommendation, I did not choose to use the chassis ground for the GROUND input on the SGI-5. I do have a wire tapped in to the chassis ground, just in case, but the wire is not connected and it is sealed.

1bad91Z

iTrader: (1)

91Z - does it matter what T-56 VSS wire you use for sig. input and how do I know what VSS wire is A or B? Also, you said you grounded the 700r4 (purple) wire into the Ground port of the SGI-5. Does it have to be grounded there or can I ground that to the chassis?

Do I even have to run a chassis ground wire to the GROUND port on the SGI-5 or is the box self-grounded?

Oh yea, I noticed that some people with 91-92's are using out3 and some are using out4. Why is that?

Bare with me, I think I'm starting to understand it!

THanks,
Mike

91Z28-350

It probably doesn't matter, but I was looking at the diagram in the Helm manual, and I'm a stickler for details. If you look at the 700R4 VSS connector (you may have to take apart some of the plastic), you will see imprinted into the connector A and B, indicating which wire is A and which is B. With your new T-56 VSS connector, imprinted in the case, there is an A and a B also. I matched those up and marked the wires with a magic marker so I know which is which just from the wires.

The SGI-5 is not self-grounding. A chassis ground should be fine, but I wanted to keep the wire lengths the same to minimize any interference....not really necessary with low current and short runs like in a car, but what the hell.


Yes, you need a ground wire. It is the reference point for the signals.

I'm not entirely certain myself. If I hit any problems, I'll hook it up to a scope to validate the configuration, but that's more trouble than it's worth at the moment.