TEDSgrad

iTrader: (4)

I have the 140 speedo, had L98 & 700R4, now have LS2/4l65e.
Finally getting around to wiring my Dakota boxes in. Buffer box already removed - no tach signal and speedo pegs at about 30 mph.

Tach - should I splice into C1 wires to wire up the SGI-8? OR 207 (E & F)? I'm thinking C1 pin 11 (white wire) from ECM into SGI-8, out of SGI-8 to into that wire, and t-splice into C10 & C9 for power & ground

Speed - C1 pin 8 (brown wire) cut and ECM side into SGI-5, out of SGI-5 into that wire, t-splice into pin 6 for power and C9 again for ground.

Brian

mille_3

iTrader: (3)

Not sure how similar the 87 is to the 89, but on my swap I wired the tach to cavity C on the 207 connector(Brown/White wire) and speedo to cavity K (Brown wire)

TEDSgrad

iTrader: (4)

87 & 89 are similar as far as gauge cluster.
Yes, I wired the speedo into 207k, and tach into 207c.
Speedo reads very high, and no response at all from tach. Jumped F & C from buffer box, too.
Would rather solve at these points then trying to go after instrument gauge C1. Too far downstream if my prob is back at 207.

mille_3

iTrader: (3)

To get the tach to work, you'll have to wire in a resistor inline. Can't remember exactly which resistor. I'll look it up and post back

five7kid

iTrader: (14)

Might need to provide a voltage bump for the tach signal. A problem only 'Birds had, apparently.

Speedo might be a setting in the PCM. Or, at least, you might be able to fix it by changing the VSS output parameters.

mille_3

iTrader: (3)

Here you go. This should make your tach come alive

http://www.lt1swap.com/lsx_tach.htm

TEDSgrad

iTrader: (4)

Thanks, guys. Since I've had the boxes for a year now, might as well use them. Bump in voltage would be provided as well. Can I use the brown/white wire at 207? It's coming from PCM, correct?
I'll do the same with the Speedo wire going to 207. I'll just need to find 'hot in run' and ground to power the boxes.

TEDSgrad

iTrader: (4)

If the speedo is a simple tuning fix, here's a screen shot. Is everything correct, here?

mille_3

iTrader: (3)

You might want to direct that to someone on the HP tuners forums, as I'm not familiar with HP tuners. But as long as you have the proper tire height in there, you should have the correct speedo readout.

Did you ever get your Tach working?

five7kid

iTrader: (14)

The output from the PCM to the speedometer should be 4000 pulses per mile.

You should be able to use the Gear/Tire Calc tab get the output correct.

TEDSgrad

iTrader: (4)

Yes, I'm aware I need 4,000 ppm to speedo. Just not sure if its configured correctly. Here are two shots of both tabs in Hp.
Haven't wired the tach, yet. OEM GM weatherstripping finally arriving tomorrow. Will spend most of my time sealing everything up this week. Body & paint will be completely finished . Runs great - just don't know how fast I'm going - I'm sure the officer will believe that .
Anyway, I'm trying to get it working so I can show it off at the Midwest F-body track day @ Road America, May 4th. Won't be ready for on-track, but I can show it off.
Eventually, I believe that I'll have to wire in the boxes to get cruise control working with the DBW. For now, I just need it sealed up and to know how fast I'm going.
Brian

five7kid

iTrader: (14)

Got a Garmin?

TEDSgrad

iTrader: (4)

Have access to one.
From hp tuner forum it appears that the pulse figures are calculated from tire and gear. Posted there, but no reply, yet.
Looks like I'll put in the boxes. Have to remove dash pad and instrument bezel to gain access to the c1 & c2 plugs. Pondering where/how to mount the boxes.

TEDSgrad

iTrader: (4)

Got the weatherstripping done, so I'll concentrate on this issue next week.
Here's a pic of completed body & paint.

five7kid

iTrader: (14)

I don't know if we have different HP T versions, but my Speedometer General tab has VSS pulses per: then has values for per mile (128,380), and per rev of transmission (40.0000). Next has VSS Output pulses per: then has values for mile (4000) and mile-ABS (128,000). Then has final drive ratio (3.73), and trans revolutions/mile (3134 - an auto entry from the calc tab). Something tells me your final drive ratio values (different fields than mine) should not all be 3.27.

In the Gear/Tire Calc tab, looks a lot like yours.

(Sorry I didn't do a screen shot, for some reason it didn't seem to want to work.)

TEDSgrad

iTrader: (4)

In hp t, control-alt-print screen to copy; then open Paint;edit and paste;save as jpeg (got that off their forum site).
Finished weathersripping, adj doors & windows, and put door panels back in. Speed & Tach and side moldings are all that's left.

Lonnie P

Putting the side moldings back on? I'm having a hard time doing it on mine... looks so clean without them.

TEDSgrad

iTrader: (4)

Lowers the car and makes it sleeker and breaks up the big door a little.
My car is a driver (gotta get my money back out in transportation value) so the function is necessary,too.


Check this article out for design & style: https://www.thirdgen.org/forums/hist...omy-style.html

TEDSgrad

iTrader: (4)

Here is a sample file for a Camaro. Appears to be what you guys are used to.
Here is a sample file of PCM E40 from GTO. Very close to what I'm seeing.

The E40 is certainly different! But I should still be able to program through HP Tuners to get the speedo where I want it.

TEDSgrad

iTrader: (4)

Will try to wire up the boxes, tomorrow.
Anyone know what switched power source to use over by the C207?

TEDSgrad

iTrader: (4)

wired the boxes in, have switched power. Tach doesn't budge, speedo has erratic readings in park.

Maybe my speedo readings are off because I should be using a 2000 ppm?

mille_3

iTrader: (3)

Maybe I missed it somewhere, but are you using digital gauges?

Did you wire in a resistor for the tach? If you haven't you'll never get the tach to work. The speedo should work directly off of the vss input and as long as your tire diameter and gearing is correctly programmed it should work (whatever pin your vss is on needs to connect to pin K on C207). If you are getting erratic readings on the speedo, you may want to go back over the connections at C207.

TEDSgrad

iTrader: (4)

Using the stock electronic 140 Speedo.
I believe the Speedo wiring to be correct, just my programming of the box, have some ideas.
Tach, box has an option of standard or high voltage output signal - wired the standard as a starting point. Tach won't prevent me from driving/ using the car, Speedo will.
Can't work on it today, but will research and call Dakota tech support today. Have an hour or two Sat morning to implement, or I'll miss the f- body event.

TEDSgrad

iTrader: (4)

Called Dakota Tech support. They said the speedo line has a "dirty" signal, late model GM gauges have internal filter for it.
They sent me this diagram to filter the signal - provided that my signal registers 12v. If different then 12v - no luck for me. I'm electrically illiterate but have a voltmeter. How do I use it to check the signal?
Attached is the diagram. I'm assuming that the Dakota box goes to the position that I indicated in red - their diagram is black. Don't understand why to ground the signal, but still use the signal. More confused as I go.

Never heard any of this before.

Tach should not be a problem, though I may have to manually calibrate it. I guess I don't learn, till I have to learn

mille_3

iTrader: (3)

Explain why you are using the dakota boxes if you are using stock equipment? Not knocking ya, just not understanding what you are trying to accomplish with them?

You shouldn't need any additional aftermarket equipment once you have wired vss and tach (plus resistor) to C207.

Maybe '89's are different from '87's?

TEDSgrad

iTrader: (4)

Was told I needed them. Now I know I didn't need the tach box.
Electrical stuff I just don't understand. Problem is everyone has a different solution, and none has worked, yet. The Dakota speedo box may (again, different solutions) be needed to get the cruise control working at a later date. Not sure why I couldn't solve the speedo problem for now by using HP Tuners.
I know I'm getting A signal to the speedometer - whether it's in the right format or a dirty signal, I have to figure out.

VSS signal is part of harness - up the trans, connect with main harness, and through the fender hole to stock position E40 & T42 ECM's. LS2 uses separate TCM. E40 ECM then sends the speedo signal out, which I have connected to C207 k - the brown wire.

mwfrels

From the 2006 GTO service manual: "The PCM creates the vehicle speed output signal by rapidly grounding this circuit via an internal switch called a driver. The driver operates at the same rate as the vehicle speed sensor (VSS) signal input."

Not sure what PPM the GTO VSS is but if 40K/mile like the 4th gen camaro and other cars that is possibly your issue. It's probably not 2K or 4K PPM. Just a hunch based on the documentation.

M

TEDSgrad

iTrader: (4)

Thanks Mike. Watching your AC progress with interest!
I believe that's accurate, and I need the Dakota for the speedo. They gave me some options to try and that filter for a "dirty" signal (not time for that, tomorrow).
Pocket posted this '92 Buffer diagram, but Jay said that '89 is 2000ppm for the speedo gauge. I'll try that, tomorrow - anyone have an '89 diagram to confirm?

mille_3

iTrader: (3)

Good luck. Let us know if that works

mwfrels

I am kinda confused by the C1 pins you say you are using:
These are from my ’06 GTO manual:



Maybe I misunderstand or maybe these help.

M

TEDSgrad

iTrader: (4)

Instrument cluster C1.
I decided against that. I'm getting readings - too slow @ 2000ppm output, and too high at 4000. In park, I get erratic readings. Tech guy from Dakota said GM LS signals are 'dirty' and have built in filters in stock gauges. Purchased the resistor and diode and will wire in in a few days.

Check your LS2 thread for a file I uploaded. It may help you

mwfrels

Duh!!!...completely forgot about those two behind the cluster. And I have no excuse because I installed a Dakota Digital dash last winter. Those two connectors was where I had to make a couple of splices. I'll go back and face my corner now...

M

TEDSgrad

iTrader: (4)

The ONLY thing to remember about corners is exit speed!

TEDSgrad

iTrader: (4)

That filter diagram worked!
On the Dakota box:
Switch #1 ON
Switch #2 ON
4000ppm signal output.

lakin454

iTrader: (2)

So just for a review, you used to dakota box for the speedo but had to wire in the resistor (from the filter diagram). And that got it to work?

Also, what about the tach? Was that fixed with the 680 ohm resistor? Or were you using a dakota box for that too?

TEDSgrad

iTrader: (4)

Correct, on the Speedo.
Have not addressed the tach, yet.
My shifter cable linkage is now giving me trouble, so I have to revisit it before the tach.

lakin454

iTrader: (2)

I need to try that to get my speedo working. I did a EFI connections 24x system on my small block so its running a 0411 pcm from an 01 silverado.

I tried hooking up the tach with a dakota box. It reads about half the rpm's that it should be reading. I think the formula tack needs the resistor to help boost the signal.