How far off would my speedometer be if I had different gears?
#1
How far off would my speedometer be if I had different gears?
Hey guys, not really sure where this belongs so I threw it in here....
I have a feeling my speedometer is off a little bit... roughly 10mph at about 80mph or so , gets worse as speed increases....
I am thinking maybe my car has had different gears installed and the speedo was never recalibrated, how much of a MPH difference might I see with a slightly larger gear, the door code says 273 and I doubt whatever is in there is much larger than like a 323 or 342.
If it is different how would I go about finding out exactly what size gear is in there??
Also when I took the car to the track the speedo read near 120mph trap speed where my ET slips were no higher than 104mph
I have a feeling my speedometer is off a little bit... roughly 10mph at about 80mph or so , gets worse as speed increases....
I am thinking maybe my car has had different gears installed and the speedo was never recalibrated, how much of a MPH difference might I see with a slightly larger gear, the door code says 273 and I doubt whatever is in there is much larger than like a 323 or 342.
If it is different how would I go about finding out exactly what size gear is in there??
Also when I took the car to the track the speedo read near 120mph trap speed where my ET slips were no higher than 104mph
#2
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it could be, do you have stock rims and tires?
you need to get exact mph error numbers then you could do some simple math to figure it out. get someone else to drive next to you at a set speed and find the difference
you need to get exact mph error numbers then you could do some simple math to figure it out. get someone else to drive next to you at a set speed and find the difference
#3
yea stock wheels and tires, I never thought about it before because I got pretty good gas mileage.
I'm gunna get my buddy to drive next to me to figure out how far its off if at all next week .
Once we do that is there a definite mathematical way to figure out the exact gearing that is in there?
I'm gunna get my buddy to drive next to me to figure out how far its off if at all next week .
Once we do that is there a definite mathematical way to figure out the exact gearing that is in there?
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Originally Posted by Luna
yea stock wheels and tires, I never thought about it before because I got pretty good gas mileage.
I'm gunna get my buddy to drive next to me to figure out how far its off if at all next week .
Once we do that is there a definite mathematical way to figure out the exact gearing that is in there?
I'm gunna get my buddy to drive next to me to figure out how far its off if at all next week .
Once we do that is there a definite mathematical way to figure out the exact gearing that is in there?
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Being able to modify the gear and rim/tire parameters was one of the main reasons I got my Predator tuner. You could just find a shop to change it for you for $50...
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Damn some of your speedos are off I would be getting tickets left and right if mine was that off. I have 2.73 gears in my 99 auto T/A and cruising on the highway at 2,000 RPM's I am doing 80mph