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OK, so I did my own Z Cluster for my RMW and i've got it working pretty well except for a couple of minor issues. My biggest issue is that I can't seem to get the speedo to indicate the correct speed. I reflashed with the Hypertech because I have 20's and wanted to correct the speedo for the time being until my engine configuration is completed and I can do a real/good reflash. When I programmed the Hypertech I indicated that I have 2:93's due to my wagon having the tow package and did the calculations indicated in the owners manual to correct for the changed tire/wheel size. I've used the HVAC display to display the speed and the speedo matches the HVAC display but they're both off by 10 MPH. I've been pulled over three times and the cops have been pretty cool once they see how my cluster looks but eventually someones gonna give me a ticket. Anybody have any ideas on what I should do here?
 

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If it is always out 10 MPH no matter the speed then something is really wrong.
More likely, it should be a percentage.
Like, if if it reads 50 at 60, at should read 25 at 30, 100 at 120 .

If it is, keep fudging the gear ratio till the speedo comes around.

Or buy a cable, read the flash, email it to me and I will try to help.
Gerry

Edit, being a 96 finding a cable will be more involved. While I could still adjust a TC BIN, if you found someone with TC OBD2 , they could adjust it also.
 

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or drive 10 MPH slower :)

my bone stock 92 L03 reads about 10 off. It says 90, my gps says 79, etc.
dunno why, but my 16 year old will get it as his first car so I may not mention that little tidbit when he drives it :)
 

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or drive 10 MPH slower :)

my bone stock 92 L03 reads about 10 off. It says 90, my gps says 79, etc.
dunno why, but my 16 year old will get it as his first car so I may not mention that little tidbit when he drives it :)
Try going 1 tooth smaller on the driven gear of your VSS. Should be a lot closer. It may take a 2 or 3 tooth smaller gear, and still be within an acceptable range. I was told 5 mph error @ 50 mph = 3 teeth. I would try 1 tooth first, and if it improves by 1.5 mph @ 50 mph, then 3 teeth is correct. They come with a 42 tooth driven gear.
 
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