Question about a VLSD on a '92 S13

[vutony]

I bought an '92 SE S13 with Vlsd in already but the odometer doesnt read correctly, its about 10-15 mhp faster. Is there a way to fix it? Not sure wat if came off of but it has 5 bolts on the axles so I think is from a J30 or Z32 but not sure. Plz help, thanks in advance.

[9240sx]

Could also be a Jdm s13 vlsd.

[SpeedRacer1]

The S13 JDM VLSD's have the same ring gear as the USDM S13 differentials.

You could try swapping the ring gear and drive pinion out of a USDM differential.

[BoostFab]

I bought an '92 SE S13 with Vlsd in already but the odometer doesnt read correctly, its about 10-15 mhp faster. Is there a way to fix it? Not sure wat if came off of but it has 5 bolts on the axles so I think is from a J30 or Z32 but not sure. Plz help, thanks in advance.

the vlsd doesn't affect your speedometer.

did you swap the speed sensor from the one off your ka's....make sure you done that ..otherwise your speedometer will be significantly off, like such.

[vutony]

Im not sure if the previous owner did it or not, which speed sensor do I need???

Thanks

[9240sx]

also if you have aftermarket rims bigger or smaller that affects you speed read out.

[SpeedRacer1]

The speed sensor from the SR and KA are the exact same. The part numbers are the exact same. The gears have the same number of teeth.

[RMiller]

Could be z32 or j30, they have different final ratios right?

[c-rad]

No, they are both 4.08 (NA Z32 anyway). Even still, the diff won't affect the speedometer regardless of drive ratio.

[UsedToOwn240SX]

You might have gotten S12 VLSD with 4.363 final ratio (48:11) instead of the 4.083 in our S13 (49:12). My VLSD was 4.363. It will reduce the actual speed you're travelling.

Try have the back wheels off the ground and start turning the back wheels while monitoring the driveshaft. For a 4.363 ratio, your rear wheels will travel 4.363 revolution for 1 driveshaft revolution. The same idea works for any kind of final ratio.

[ETTInnov04]

Are the factory wheels/ hubcaps still on the car? Make sure the correct tire size is on there. I'm running 215/45/17 all the way around and I normally read about 2-3 mph below my actual speed. General Rule of thumb: Every inch you increase in wheel size you take 10 off of the sidewall. Your tire sidewall my be too short.

[RobDET]

The speed sensor from the SR and KA are the exact same. The part numbers are the exact same. The gears have the same number of teeth.

When i did my swap it was convention to change the speen sensor out. Am I wrong about that? I thought that was one of the things you just had to do... Has the consensus changed? I've been off the boards for a while.

[SpeedRacer1]

Heavy throttle started telling everyone there was no need to swap the speed sensors about a year ago. Ive checked the part numbers since then and they are the exact same.

[RobDET]

Cool. One more USDM part we can use! That makes sense sence the tach looks the same it just has numbers in a different place.