2.56 vs 2.73 performance ratio option ??
04-19-2009, 05:08 PM
#1
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2.56 vs 2.73 performance ratio option ??
My 2008 A6 coupe has the 2.73 performance rear axle ratio(GU2) .
Does this mean my vette will be slightly quicker off the line than a 2.56 equipped car.All else being equal
Will I also loose a little in terms of top end performance ?
Will my top speed be slightly lower than a 2.56 equipped car ?Or is 6 gear a little taller in the 2.73 equipped cars to give them the same top speed as the 2.56 cars ?
I am sure there are a few guys out there that can answer my questions
Regards
Rick from Winnipeg Canada
Does this mean my vette will be slightly quicker off the line than a 2.56 equipped car.All else being equal
Will I also loose a little in terms of top end performance ?
Will my top speed be slightly lower than a 2.56 equipped car ?Or is 6 gear a little taller in the 2.73 equipped cars to give them the same top speed as the 2.56 cars ?
I am sure there are a few guys out there that can answer my questions
Regards
Rick from Winnipeg Canada
04-19-2009, 05:27 PM
#2
My 2008 A6 coupe has the 2.73 performance rear axle ratio(GU2) .
Does this mean my vette will be slightly quicker off the line than a 2.56 equipped car.All else being equal
Will I also loose a little in terms of top end performance ?
Will my top speed be slightly lower than a 2.56 equipped car ?Or is 6 gear a little taller in the 2.73 equipped cars to give them the same top speed as the 2.56 cars ?
I am sure there are a few guys out there that can answer my questions
Regards
Rick from Winnipeg Canada
Does this mean my vette will be slightly quicker off the line than a 2.56 equipped car.All else being equal
Will I also loose a little in terms of top end performance ?
Will my top speed be slightly lower than a 2.56 equipped car ?Or is 6 gear a little taller in the 2.73 equipped cars to give them the same top speed as the 2.56 cars ?
I am sure there are a few guys out there that can answer my questions
Regards
Rick from Winnipeg Canada
Yes top end will be a tad slower if you do a lot of driving above 180+.
5th. gear will be your top speed gear. 6th. is to tall to hold top speed.
Given the choice I would rather have the 2.73 gears over the 2.56 I have in mine.
Last edited by Flat Broke; 04-19-2009 at 05:31 PM.
04-19-2009, 07:00 PM
#3
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Definitely maybe...
My 2008 A6 coupe has the 2.73 performance rear axle ratio(GU2) .
Does this mean my vette will be slightly quicker off the line than a 2.56 equipped car.All else being equal
Will I also loose a little in terms of top end performance ?
Will my top speed be slightly lower than a 2.56 equipped car ?Or is 6 gear a little taller in the 2.73 equipped cars to give them the same top speed as the 2.56 cars ?
I am sure there are a few guys out there that can answer my questions
Regards
Rick from Winnipeg Canada
Does this mean my vette will be slightly quicker off the line than a 2.56 equipped car.All else being equal
Will I also loose a little in terms of top end performance ?
Will my top speed be slightly lower than a 2.56 equipped car ?Or is 6 gear a little taller in the 2.73 equipped cars to give them the same top speed as the 2.56 cars ?
I am sure there are a few guys out there that can answer my questions
Regards
Rick from Winnipeg Canada
Even if you lived in Germany it is doubtful you would notice the difference in top end. The perfect conditions (traffic and weather) you would need to explore and appreciate any difference in top end are rare and fleeting. Nuances at 180-190mph are silly in this country.
On the other hand, the 2.73 should give you a slight edge in acceleration...although some of the hot shoes with 2.56 ratios may still show you their tailights. As always, when you want to push the performance envelope, it's ALWAYS about the driver!!
Brad
04-19-2009, 07:02 PM
#4
Burning Brakes
Rick, i don't think you could tell the difference between the 2.56 and the 2.73 in a A6 since it's such a small gear change and don't think there would be any difference in top speed..... but if i had my choice i would have chosen the 2.73 over the 2.56's in my car
Last edited by da vette guy; 04-19-2009 at 07:04 PM.
04-19-2009, 10:54 PM
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St. Jude Donor '13
Actually, I think the 2.73 will give a slightly higher top speed because it allows the engine to get closer to peak HP rpm.
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Tom Terrific (07-28-2019)
08-10-2011, 01:31 PM
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08-10-2011, 02:09 PM
#7
Race Director
Difference between the too would be minimal , you might feel a slight bit quicker off the line... but other than that I bet the average person would not be able to tell a difference. In terms of Top End...as someone else posted, you would need a race-track to be able to get up that fast to test the too.
My guess would be the 2.56 car would be just a tick higher in terms of top end speed.
My guess would be the 2.56 car would be just a tick higher in terms of top end speed.
08-10-2011, 02:20 PM
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St. Jude Donor '13
There is a gear vs speed calculator online, I've used it but don't have the link anymore. Hopefully, someone will post the link.
IIRC, even the 2.73 is too tall for best top speed in 5th, and 6th is hopelessly tall.
The difference at 180 mph is pretty small, a couple of hundred rpm. But every little bit helps when you are below peak HP rpm.
IIRC, even the 2.73 is too tall for best top speed in 5th, and 6th is hopelessly tall.
The difference at 180 mph is pretty small, a couple of hundred rpm. But every little bit helps when you are below peak HP rpm.
08-10-2011, 02:31 PM
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There is a gear vs speed calculator online, I've used it but don't have the link anymore. Hopefully, someone will post the link.
IIRC, even the 2.73 is too tall for best top speed in 5th, and 6th is hopelessly tall.
The difference at 180 mph is pretty small, a couple of hundred rpm. But every little bit helps when you are below peak HP rpm.
IIRC, even the 2.73 is too tall for best top speed in 5th, and 6th is hopelessly tall.
The difference at 180 mph is pretty small, a couple of hundred rpm. But every little bit helps when you are below peak HP rpm.
08-10-2011, 02:36 PM
#10
Team Owner
There is a gear vs speed calculator online, I've used it but don't have the link anymore. Hopefully, someone will post the link.
IIRC, even the 2.73 is too tall for best top speed in 5th, and 6th is hopelessly tall.
The difference at 180 mph is pretty small, a couple of hundred rpm. But every little bit helps when you are below peak HP rpm.
IIRC, even the 2.73 is too tall for best top speed in 5th, and 6th is hopelessly tall.
The difference at 180 mph is pretty small, a couple of hundred rpm. But every little bit helps when you are below peak HP rpm.
http://mysite.verizon.net/foofoo2/c6/
08-10-2011, 03:25 PM
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2021 C6 of the Year Finalist - Modified
08-10-2011, 04:06 PM
#13
Team Owner
I felt the same way while my car was stock. Now that Im S/C'd I think Im quite happy with the 56's. Its hard enough to get traction as is and when when I matt the throttle the gearing seems perfect(to me) for maximum acceleration. Not to mention a wee bit better mileage for those long weekend road trips.
08-10-2011, 04:08 PM
#14
Le Mans Master
Here's a few numbers you may find interesting. Both axles sound like real whimps, unitil you figure in the A6's 4.05 1st gear ratio. Comparing 60's cars A3's had 2.5 1st gears. Even with the 2.56, 1st gear is like a 60's C3 w/4.11 axle.
08-10-2011, 04:12 PM
#15
Team Owner
