Calibrate speedo

[cnoyez1]

How do I calibrate my speedo on my 93 HB? Thx

 

[Kensai]

Have ecu flashed

 

[cnoyez1]

A little over my head. What do you mean by having it flashed? It wouldn't be something simple like a screw to tighten down??

 

[TigBitties]

No it wouldnt be, and i find the best way to do this is to get the correct tire size lol but i think you have to get a device to reprogram the ecu to change the settings. Ive never done it before though

 

[reichbc]

No it wouldnt be, and i find the best way to do this is to get the correct tire size lol but i think you have to get a device to reprogram the ecu to change the settings. Ive never done it before though

I don't think tire size has anything to do with it. I'm pretty sure the speed is determined by the sensor mounted to the final output of the tranny somwehere.

 

[TigBitties]

that went way over your head i think

 

[BoostN_ED7]

that went way over your head i think

here you go stole it from CI

Tire size.............Overall diameter......Reading / Actual................Accuracy rate
205/40/16..........22.5 inches...............70mph / 60.9mph.............87% accuracy
175/70/13..........22.7 inches...............70mph / 62.3mph.............89% accuracy
185/60/14..........22.8 inches...............70mph / 63.7mph.............91% accuracy
195/50/15..........22.8 inches...............70mph / 63.7mph.............91% accuracy
205/50/15..........23.1 inches...............70mph / 65.8mph.............94% accuracy
205/45/16..........23.3 inches...............70mph / 66.9mph.............95.5% accuracy
195/55/15..........23.4 inches...............70mph / 67.9mph.............97% accuracy
205/40/17..........23.5 inches...............70mph / 69.3mph.............99% accuracy
225/50/15..........23.9 inches...............70mph / 74.2mph.............94% accuracy

 

[DeathLens]

No it wouldnt be, and i find the best way to do this is to get the correct tire size

x2

 

[ImThaBean]

the best way to do this is to get the correct tire size

Not always the case. I am running a 14" wheel but chose a tire that is the same diameter as the stock 13" wheel/tire combo. My speedo is off by +/- 10 MPH as verified by GPS. I have swapped VSS and speedos with the same result. and as such, for the EG's since they have a VSS there is no "proper" way to calibrate the speedo through the ECu since the signal is sent through the VSS. From what I have read, the best way to calibrate is to pull the needle and "manually" calibrate by getting to a certain speed, sustaining said speed and slap the needle back on the pin pointing at the correct MPH reading. I have yet to do this though..

 

[2NRSTV]

He never made it clear if his Speedo is just reading wrong or if he changed his tire size.
If the speedo is just reading wrong, take the needle off and put it back on where the like "NS"s is at about 7 o'clock on the speedo. That is the proper resting spot.

I don't think tire size has anything to do with it. I'm pretty sure the speed is determined by the sensor mounted to the final output of the tranny somwehere.

Tire size has just as much to do with proper speed reading as the proper gear ratios. If the circumference of the tire is larger, it will travel a further distance in one rotation; a lot like how gear ratios work.

 

[ImThaBean]

Just did the NS calibration/reset and my speedo is spot on now according to GPS. That is, once I hit 50 MPH. Building speed up to 50 the speedometer is about 5 MPH off. But that's good enough for me.