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Discussion Starter #1
well i originally thought that my car had 3.73s (pervious owner bought from dealer used so not much info)

well i got a tuner and tuned my car to 3.73s nothing seemed out of the ordinary, however, today i got a free speedometer app on my iphone and just tested it out for fun, and it was accurate to about 35mph there when my car goes to 40mph the app says im going 45-44 :confused:

i need some help
 

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And you haven't had the fortune of driving by one of those cop like things that tell you your speed? I wouldn't trust an iphone too much for an accurate reading right away... Did you test against another vehicle going 40?

EDIT: sry if came out rude. Just don't mistrust your like $200 tune or whatever for a $1.99 app just yet :p
 

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Punching Throats
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If your gonna do that, use a GPS. That is going to be way more accurate than an Iphone/Droid app. My GPS is only ever off by about 1 mph maybe 2 in the backwoods.
 

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Do you have a gauge overlay? Mine was off because the previous owner didn't get the speedometer needle back on in the right place. The wheels have to be turning to set it.
 

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Discussion Starter #5
well it was a free app thats why im a little skeptical but im not sure what the gears are in my car though, i dont know who put them in ill have to find my GPS but im not sure where it is.
 

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To check your gears, jack up the back of the car. Turn the rear wheel one revolution anc count the number of times the driveshaft turns. 3 1/4 = 3.27, 3 3/4 = 3.7s. etc.
 

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Discussion Starter #7
well i did the fourth gear at 40mph and looked at the rpms.. that said i had 3.73s however not i noticed fourth gear 40mph has my rpms a little higher now
 

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Discussion Starter #9
okay i think i found the problem, when i ordered the new tunes from bama, they had a new thing where they asked for what brand my gears were but i didnt put what brand i guess? well ive noticed i only get up to 50mph in second gear which isnt right, it should be around 60.

so is there a way to adjust the speedo with the tuner, or will i just have to get more tunes?
 

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I wanna SPRAY!
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Sorry I can't answer your question but the GPS apps I have found to be fairly accurate. The speedview app on my HTC Aria reads within 1mph of my GPS.
 

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okay i think i found the problem, when i ordered the new tunes from bama, they had a new thing where they asked for what brand my gears were but i didnt put what brand i guess? well ive noticed i only get up to 50mph in second gear which isnt right, it should be around 60.

so is there a way to adjust the speedo with the tuner, or will i just have to get more tunes?
You can adjust the rear end ratio in the options on an SCT device. Just go to re-load the tune and hit up "Adjust Options" find the rear end option and set it for 3.73s. If you're running a bigger/smaller tire that will also affect your speedo. You can change that at the same time. All you have to know is your specific rear tires "Revolutions per mile"
 

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Discussion Starter #13
this is what i did... okay well this **** is making me mad lol.

okay so,
when im tuned to 3.73s my car says im going 40mph, however im going around 45mph
when im tuned to 4.10s my car says im going 40mph, however im going around 50mph
when im tuned to 3.55s my car says im going 40mph, however im going around 40mph
when im tuned to 3.55s my car says im going 60mph, however im going around 65mph

at 60mph (according to gps) in fifth gear im at around or very very close to 2k rpms
now according to that gear thread that would mean i have 4.10s

now my tires are 17inch rims 275/40/17 could this have to do with it...
i really want to know what gears are in my car, but i just dont think they are stock. but they could be maybe?
 

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I wanna SPRAY!
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Looking at this gearing chart 3.90's are the only gears putting your rpm's close to 2,000 at 60mph. Looks to be a toss up between 4.10's and 3.90's. You sure the tire size input is correct on your tuner?


PaladinMicro
 

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Discussion Starter #15
no lie im about to lose it and go apeshit on my car lol.... ill check the tires on the thing tomorrow. but 275/40/17 all around sounds right for the car right? thats not off from stock really?
 

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no lie im about to lose it and go apeshit on my car lol.... ill check the tires on the thing tomorrow. but 275/40/17 all around sounds right for the car right? thats not off from stock really?
I was just asking cause the SCT tuner like mine requires the tire sizes to be converted into milimeters before entering it into the tune.
 

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I wanna SPRAY!
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It sounds to me like if none of the gear sizes you tried in your tune corrected the speedo then you have problems elsewhere. Although you didn't try 3.90's.
 
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