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Do i REALLY have 2.73's?

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Old 09-06-2007, 06:45 AM
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Default Do i REALLY have 2.73's?

Ok sry again for so many questions, but i KEEP ON seeing posts saying where 2.73 geared A4, can kickdown to first from 39-40. Mine wont go past 28mph! Do u think the previous owner swapped in 3.23's! I have the GU2 code. What else would explain my car not kicking down from at Least 30 mph with 273s!!?
Old 09-06-2007, 07:05 AM
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how many RPMs are you running at 65mph in 4th?
Old 09-06-2007, 07:39 AM
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Do you have a steel driveshaft? If so you have 2.73s if you have an AL you need to make sure what you have but likely you will have 3.23s
Old 09-06-2007, 07:41 AM
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My old car would run around 2k rpms at 90 if I remember right.
Old 09-06-2007, 08:16 AM
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no thats correct. i believe with 2.73s in an a4, on stock tuning, your car can downshift from 3rd to 1st at any speed under 31 mph.
Old 09-06-2007, 08:30 AM
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I have 2.73's and can downshift from 4th to 1st at 35 mph. The cutoff is somewhere between 35-36 mph. If your car won't kick down to first at 31-35 mph, that could mean a few things:

1.) Someone changed the stock tuning to not allow for it
2.) Your speedometer is off a few mph
3.) You don't have 2.73's

#3 is probably the answer. Go cruise at 70 mph and tell me what your RPMs are.
Old 09-06-2007, 09:10 AM
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you post a video before of your 0-60... find the vid and look at then its shifting
At Wide open throttle...
2.73's the 1-2 shift will happen just over 50mph
3.23's I think the 1-2 will happen around 45mph
Old 09-06-2007, 09:41 AM
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Originally Posted by ChocoTaco369
I have 2.73's and can downshift from 4th to 1st at 35 mph. The cutoff is somewhere between 35-36 mph. If your car won't kick down to first at 31-35 mph, that could mean a few things:

1.) Someone changed the stock tuning to not allow for it
2.) Your speedometer is off a few mph
3.) You don't have 2.73's

#3 is probably the answer. Go cruise at 70 mph and tell me what your RPMs are.
Yep.

I can get a downshift to 1st at up to 36-37mph with my 2.73 car. Every time.
Old 09-06-2007, 09:55 AM
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Do you want to absolutely, positively certain? Change your rear lube. While the cover is off, count the number of teeth and do the math. # of teeth on the ring divided by the # of teeth on the pinion.
Old 09-06-2007, 12:09 PM
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Originally Posted by ThumperNC24
how many RPMs are you running at 65mph in 4th?
1600
Old 09-06-2007, 01:31 PM
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http://youtube.com/watch?v=6dRf9eDBxU4
i kno my car shifts at 45 mph, its a lil hard to tell with tht video screen being small, and my shift kit kickin up the speedo a bit, but yea do shift at 45 mph, does tht mean i have 323's or could i still have 273s?
Old 09-06-2007, 02:52 PM
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easiest way to tell is like what was stated above. Get on the highway in overdrive, do 60mph or 70mph, check your RPM, and report back to us. FYI at 70mph I'm at 1700ish rpm, and I've got the 2.73's. 3.23's will be about 2100 rpm at 70.
Old 09-06-2007, 02:56 PM
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Originally Posted by sixvi6-camaro
you post a video before of your 0-60... find the vid and look at then its shifting
At Wide open throttle...
2.73's the 1-2 shift will happen just over 50mph
3.23's I think the 1-2 will happen around 45mph
Unless my speedo is way off, that can not be correct. My 3:23 car shifts at 35 at WOT, and my 3:08 Camaro shifted at 40 t WOT.
Old 09-06-2007, 07:32 PM
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The best way would be to get on the highway as stated above but looking at the video above it seems like it just may be 3.23's. Its shifting at redline around 45mph.

hurley_21_07.. Is it shifting at 35mph right at redline? doesn't sound right at all to be shifting that early at WOT. If the spedo is that far off you should get a tune because the shift points, shift firmness, Lockup speeds.. all kinds of things use the speed input in the car.
Old 09-06-2007, 08:24 PM
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Originally Posted by hasenbonkers
http://youtube.com/watch?v=6dRf9eDBxU4
i kno my car shifts at 45 mph, its a lil hard to tell with tht video screen being small, and my shift kit kickin up the speedo a bit, but yea do shift at 45 mph, does tht mean i have 323's or could i still have 273s?
If your car is a GU2 and you're shifting at 45 mph, you don't have 2.73's. That means someone changed the gear ratio, and I doubt they would go to 3.23's as it doesn't make much sense unless they got their hands on a full rear end for a great deal. My guess is it has 3.42's in the rear. The only way we're going to know is if you give us a cruising RPM. Please tell us what your RPM is in overdrive at 70 mph, or 60 mph, or 55 mph. As long as it's overdrive and locked up.

45 mph may be a little high for a 1st to 2nd gear upshift with 3.42's though...
Old 09-06-2007, 09:01 PM
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ok i will, im leaving for work soon. So when i get to 70 mph, do i look at the rpms when im barely touching the gas, or when i push it just enough to where it accelerates and the rpms rise?
Old 09-06-2007, 09:17 PM
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Get the RPM reading while you are holding the speed continuously with the throttle at 65 or 70mph.
Old 09-06-2007, 09:43 PM
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I know for a fact with 2.73's cruising at 80mph you will be at 2000rpm's
Old 09-07-2007, 06:43 AM
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yea at 70mph i was around 1950 rpms barely touching the gas
Old 09-07-2007, 08:10 AM
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then most likely there 3:23's mine sits around 2k at 70 aswell.



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