Electronic Speedo Conversion PIC HEAVY!!!!!!!

[Built6spdMCSS]

Thanks, alot of work in this car. I've heard that gauge pack mentioned a couple of times of people wanting to convert them.

The years that this speedo gauge comes from is 1990-1991 Chevy full size K5 Blazer, Surburban, GMC full size Jimmy, Chevy/GMC full size C10/20/30 Gasoline Van (not diesel from what some people have said but I don't see a difference in the speedo so I'm not sure).

The Blazer Speedo faceplate was 85mph, but that doesn't really matter really when you have the software and just tune the Speedo pulse per mile to dial it in accurate. I mentioned that in the video there.

 

[Built6spdMCSS]

I had some time to make this look exact as it came, someone asked if I could do it.

I machined the original needle for the electronic speedo and drilled it out to where the Monte SS Needle could press in by hand. It fits perfect and looks exactly like it should now.

 

[ssn696]

Impressive engineering. 1990 C/K speedos will be the next thing to disappear form all the yards like the Blazer spindles have.

 

[bills80sElCamino]

Very nice, I'm no where near doing this swap yet, but is there any information on the software that's used to calibrate the speedo?
Sorry to revive a dead thread too.

Bill

 

[Built6spdMCSS]

On the previous page there is a video, I use my HP Tuners to calibrate it with the PCM.

 

[bills80sElCamino]

Thanks, I watched the video but I didn't know what software that was.

 

[Ribbedroof]

When you say 90/91 C10/20/30, I assume you mean the R/V (square) body style? As I recall, the 88+ C/K trucks used a different cluster.

R/V series would be Suburban, K blazer, any of the "old" square style after the '87 model year

Thanks for posting, should make electric speedo conversion a lot easier

 

[Built6spdMCSS]

When you say 90/91 C10/20/30, I assume you mean the R/V (square) body style? As I recall, the 88+ C/K trucks used a different cluster.

R/V series would be Suburban, K blazer, any of the "old" square style after the '87 model year

Thanks for posting, should make electric speedo conversion a lot easier

C10/20/30 VAN, not a truck. Has to be the full size Van, so most likely that older style.

 

[Ribbedroof]

Ah, that would be a G10/20/30. C series is pickup, G series is van.

 

[Jrz126]

The Blazer Speedo faceplate was 85mph, but that doesn't really matter really when you have the software and just tune the Speedo pulse per mile to dial it in accurate. I mentioned that in the video there.

Won't the Odometer be incorrect if you swap faceplates and tweak the pulses per mile in the ECM?

I grabbed one from a G20 Van. Rigged up an arduino to generate the pulses. Found the odometer is set for 4000 pulses per mile. 66.6 Hz = 4000 pulses in one minute, which should be 60mph. My needle was pointing to ~50mph, but i think i just need to tweak the "0" point since i had a 10mph shift at all speeds.

Thanks for the writeup. Wouldnt have known what to look for in the junkyard without the pics.