Speedometer updates? er, fixed, kinda..

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charged3800z24
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Speedometer updates? er, fixed, kinda..

Post by charged3800z24 »

MS3/MS3x
Buick 3800 v6
4t65e-HD w/ vr Speed Sensor
1.0.5a Code

Still using a GM 4t65e HD tranny with VR 2 wire sensor connected to MS3X VR input. I am currently on 1.0.5a code. I am using a 1992 Speedo from a Cavalier.
I haven't been able to get this to work correctly yet and would love to soon. Looking at driving the car more regularly. The last beta cde used was Aplha18, almost had it working. Speed would jump around a lot at low speeds as well as other weirdness. Any new improvemnents in this area in next release?

Thanks

Jay
Last edited by charged3800z24 on Mon May 14, 2012 7:19 pm, edited 1 time in total.
charged3800z24
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Re: Speedometer updates in 1.1?

Post by charged3800z24 »

Any body running GM Speedo? using 2-wire VR? :shock:
Will this have any updates in future versions? Just curious.

Thanks,
Jay
93white3400z
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Re: Speedometer updates in 1.1?

Post by 93white3400z »

I have used speedo output with 1.0 and 1.1 code without issue at all. That's with my 93 cavalier with 2 wires VR sensor. Only improvement in 1.1 for me was to be able to specify scaling factor in PPM which makes more sense, but beside that, I never had a bouncy speedo at all.

Attached is my pre 1.1 beta 20 MSQ, hopefully that can help you.
1993 Chevrolet Cavalier Z24
3400 Turbocharged Inter-cooled
MS3 v3.57+MS3X
charged3800z24
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Re: Speedometer updates in 1.1?

Post by charged3800z24 »

Thanks, ya you helped me last time. Did you use a shielded wire or just a twisted pair? I'll try Alpha 20 and see how it does. I see you can set 4000ppm which 1.0.5a doesn't have.
93white3400z
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Re: Speedometer updates in 1.1?

Post by 93white3400z »

I'm not sure about the wire, I just used whatever was there already :)
1993 Chevrolet Cavalier Z24
3400 Turbocharged Inter-cooled
MS3 v3.57+MS3X
charged3800z24
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Re: Speedometer updates in 1.1?

Post by charged3800z24 »

I don't have the original wire. I used a twisted pair from a CAT 5e wire. I believe the factory wire for the buick tranny had a 18awg stranded copper that was twisted.
charged3800z24
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Re: Speedometer updates in 1.1?

Post by charged3800z24 »

OK, tried your settings. Only thing is I have a different input settings due to my 4t65e_HD drive sensor has 31 teeth. I also do not have the gear ratios set for each gear (below Method in gear detection). My guage didn't move till I reached what felt like 50mph. Then it was working past that point but was about 30mph off once I was doing about 65, guesing based off rpm in 4th gear.

Another note: I am using Tacho Out, you are using Nitro out. I asume this shouldn't be an issue.
charged3800z24
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Re: Speedometer updates in 1.1?

Post by charged3800z24 »

Ok, switch the output to Nitros1 and set the gear ratios. I do have the Tuner Studio gauge working and it seems close. I will check this next weekend with the GPS, ran out of time today.
My car gauge still jumps around and never reads any speed.
My setup, I pulled the gauge from the 92 cluster and mounted it in my 89's. The board is under the dash and has the three wires running and soldered to the pins on the baqk of the gauge. The board the gauge was attached to has fused/switch 12v amd Ground. The Gauge input comes from the nitros 1 on the MS3X. I had this almost working back on Alpha14, but never 100%. So I can't imagine the wiring is now wrong, lol. Not sure what to do now, might see about an after market gauge. I really was hoping to keep a factory look though.
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Re: Speedometer updates in 1.1?

Post by jsmcortina »

The "tacho" output is a 0-12V signal.
Nitrous1 (as standard) is a switched ground only - it doesn't generate 12V. You would need to add a pullup resistor if that is required.

James
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charged3800z24
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Re: Speedometer updates in 1.1?

Post by charged3800z24 »

jsmcortina wrote:The "tacho" output is a 0-12V signal.
Nitrous1 (as standard) is a switched ground only - it doesn't generate 12V. You would need to add a pullup resistor if that is required.

James
Just saw this in the manual while trying to figure this out. Thanks! I'll switch and see what happens again.
charged3800z24
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Re: Speedometer updates in 1.1?

Post by charged3800z24 »

93white3400z wrote:I'm not sure about the wire, I just used whatever was there already :)
Can you tell me how yours is wired in some details? Sensor to MS and MS to gauge. I saw you were using the Nitros1 output. My circuit board from the 92 had a Signal connection from the PCM and I thought I read this was a 0-12v signal?
93white3400z
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Re: Speedometer updates in 1.1?

Post by 93white3400z »

Cam in on MS3X: B9 on stock ECM
Nitrous 1 on MS3X: to speedo in gauge cluster
B10 on stock ECM to ground
1993 Chevrolet Cavalier Z24
3400 Turbocharged Inter-cooled
MS3 v3.57+MS3X
charged3800z24
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Re: Speedometer updates in 1.1?

Post by charged3800z24 »

93white3400z wrote:Cam in on MS3X: B9 on stock ECM
Nitrous 1 on MS3X: to speedo in gauge cluster
B10 on stock ECM to ground
Looking at the 99 regal and the sensor on the tranny and the VSS on the 92, it seems both use yellow for Ref-Hi which in your case was B10, I put this to the MS3X Cam-In. I then put Ref-Lo (purple) to the Ground, which was B9 in your case. not sure if it matters which way, but Hi would normally be signal and Lo would be sensor ground. I'll play with it some this weekend if I have time. I thought about starting over on the wiring just to be sure.

Edit:
I also found this info, not sure if it helps for setting TS setting for the MS3.
4t65e Trans VSS info
Stock 30-tooth reluctor
Calculated_Pulses_Per_Revolution: 28.03
Pulses_Per_Mile: 22710
Drive_Sproket_Ratio: 0.89
charged3800z24
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Re: Speedometer updates in 1.1?

Post by charged3800z24 »

I rewire everything and verified it was all correct. the gauge still didn't work on Nitris1out, hopped around. I will switch back to Taho out since it use to work at one time on that just never had it acurate. Though, I am wondering if my gauge is borked.... I'll check my local yard and see if I can get a cluster.
charged3800z24
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Re: Speedometer updates in 1.1?

Post by charged3800z24 »

Ok, Speedometer is working again, just need to dial it in. I found a split trace on the circuit board. I also bought the Dual VR board from DIYautotune.com. My goal is to adventually run to wheel sensors into MS3X inputs. Anyone use this board for VSS input?
charged3800z24
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Re: Speedometer updates in 1.1?

Post by charged3800z24 »

Still on Cam-In for now on MS3X
Now on Alpha21 code
Same setup as OP
Ok, have a question for those who might know. I have the speedometer in Tuner Studio working right on the money. Checked it with GPS unit.
My dash gage is 5mph slower at 15-20 and about about 5mph faster at 60-70. I attached my MSQ if needed. My log file for today was to large.
Matt Cramer
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Re: Speedometer updates? er, fixed, kinda..

Post by Matt Cramer »

I wonder if we need a "inaccurate OEM speedometer gauge" correction table. :)
Matt Cramer -1966 Dodge Dart slant six running on MS3X
charged3800z24
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Re: Speedometer updates? er, fixed, kinda..

Post by charged3800z24 »

Matt Cramer wrote:I wonder if we need a "inaccurate OEM speedometer gauge" correction table. :)
I was actually think it was off, but I found the issue.. lol I feel pretty dumb now. I had the wrong back plate on the speedo.
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