2.93 to 3.15?
11-14-2008, 06:18 AM
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I am about to purchase a Quaife LSD from diffsonline and am wondering if changing the final drive to a 3.15 will provide a noticeable difference in acceleration or cause a significant decline in economy. If anyone could provide some insight, it would be greatly appreciated.
Thanks!
Thanks!
11-14-2008, 12:20 PM
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Originally Posted by roamer' post='720998' date='Nov 14 2008, 10:18 AM
I am about to purchase a Quaife LSD from diffsonline and am wondering if changing the final drive to a 3.15 will provide a noticeable difference in acceleration or cause a significant decline in economy. If anyone could provide some insight, it would be greatly appreciated.
Thanks!
Thanks!
First you need to have a manual or SMG trans to change gear ratios, doesn't work with Steptronic, computer gets confused. I asked when I had the Quaife installed.
Assuming no step
wondering if changing the final drive to a 3.15 will provide a noticeable difference in acceleration or cause a significant decline in economy.
There are ratio calculators on the net that tell you the change in RPM at set speeds for various gear ratios. More higher RPM on the highway, more fuel used...
11-14-2008, 02:11 PM
#3
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Originally Posted by roamer' post='720998' date='Nov 14 2008, 04:18 PM
I am about to purchase a Quaife LSD from diffsonline and am wondering if changing the final drive to a 3.15 will provide a noticeable difference in acceleration or cause a significant decline in economy. If anyone could provide some insight, it would be greatly appreciated.
Thanks!
Thanks!
About +10% consumption and more acceleration.
SMG or manual transmission, roamer?
11-15-2008, 01:58 PM
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mhs525- I tried a search, yielded nothing, thanks for your help.
Alex- I have a 6-speed. Also, there is no way there is a 10% increase in consumption. The rpm difference is only 250 rpm in 6th at 75. There is not a direct relationship between a difference in rpm and fuel used. Is fuel economy impacted, most certainly, but it is not a 1-for-1 ratio.
If someone can provide me some actual experience with the change, it would be greatly appreciated.
Alex- I have a 6-speed. Also, there is no way there is a 10% increase in consumption. The rpm difference is only 250 rpm in 6th at 75. There is not a direct relationship between a difference in rpm and fuel used. Is fuel economy impacted, most certainly, but it is not a 1-for-1 ratio.
If someone can provide me some actual experience with the change, it would be greatly appreciated.
11-15-2008, 02:06 PM
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Originally Posted by roamer' post='722188' date='Nov 15 2008, 11:58 PM
Alex- I have a 6-speed. Also, there is no way there is a 10% increase in consumption. The rpm difference is only 250 rpm in 6th at 75. There is not a direct relationship between a difference in rpm and fuel used. Is fuel economy impacted, most certainly, but it is not a 1-for-1 ratio.
If someone can provide me some actual experience with the change, it would be greatly appreciated.
AS SAID, I am the only one who did it: nobody can give you better infos than me.
11-16-2008, 07:52 AM
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Originally Posted by roamer' post='722188' date='Nov 15 2008, 05:58 PM
mhs525- I tried a search, yielded nothing, thanks for your help.
Alex- I have a 6-speed. Also, there is no way there is a 10% increase in consumption. The rpm difference is only 250 rpm in 6th at 75. There is not a direct relationship between a difference in rpm and fuel used. Is fuel economy impacted, most certainly, but it is not a 1-for-1 ratio.
If someone can provide me some actual experience with the change, it would be greatly appreciated.
Alex- I have a 6-speed. Also, there is no way there is a 10% increase in consumption. The rpm difference is only 250 rpm in 6th at 75. There is not a direct relationship between a difference in rpm and fuel used. Is fuel economy impacted, most certainly, but it is not a 1-for-1 ratio.
If someone can provide me some actual experience with the change, it would be greatly appreciated.
11-17-2008, 12:25 AM
#8
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Originally Posted by roamer' post='722826' date='Nov 17 2008, 03:50 AM
Alex-
My apologies, I thought you were speculating, it was not clear from your initial response that you had made the change in ratios. Thanks for the info!
My apologies, I thought you were speculating, it was not clear from your initial response that you had made the change in ratios. Thanks for the info!
Ok, don't worry
Keep in mind I use the car especially on freeways at (kmh) 145 or 175 (90 and 110 mph)
When do you plan to do the mod?
Now or during next weeks/months?
11-17-2008, 09:58 AM
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Alex-
I plan on doing it asap. I live in Buffalo,NY and we tend to get a fair amount of snow from time-to-time. I primarily need the diff for snow/ice traction and secondarily for performance. I was going to get the diff through diffsonline who seem to have the best prices and will ship me a complete pumpkin rather than relying on a local hack to build the diff.
My driving is primarily on the highway, but at lower speeds 70-80 mph (110-130 km/h). From a performance standpoint, was the difference in acceleration significant? Given the way fuel prices have fluctuated I am a bit aprehensive about loosing too much economy if the performance difference is minimal. . .
I plan on doing it asap. I live in Buffalo,NY and we tend to get a fair amount of snow from time-to-time. I primarily need the diff for snow/ice traction and secondarily for performance. I was going to get the diff through diffsonline who seem to have the best prices and will ship me a complete pumpkin rather than relying on a local hack to build the diff.
My driving is primarily on the highway, but at lower speeds 70-80 mph (110-130 km/h). From a performance standpoint, was the difference in acceleration significant? Given the way fuel prices have fluctuated I am a bit aprehensive about loosing too much economy if the performance difference is minimal. . .
11-17-2008, 10:18 AM
#10
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Originally Posted by roamer' post='723328' date='Nov 17 2008, 07:58 PM
Alex-
I plan on doing it asap. I live in Buffalo,NY and we tend to get a fair amount of snow from time-to-time. I primarily need the diff for snow/ice traction and secondarily for performance. I was going to get the diff through diffsonline who seem to have the best prices and will ship me a complete pumpkin rather than relying on a local hack to build the diff.
I plan on doing it asap. I live in Buffalo,NY and we tend to get a fair amount of snow from time-to-time. I primarily need the diff for snow/ice traction and secondarily for performance. I was going to get the diff through diffsonline who seem to have the best prices and will ship me a complete pumpkin rather than relying on a local hack to build the diff.
I was asking because one day I will get the supercharger and I will come back to previous ratio so I will resell parts.
My driving is primarily on the highway, but at lower speeds 70-80 mph (110-130 km/h). From a performance standpoint, was the difference in acceleration significant? Given the way fuel prices have fluctuated I am a bit aprehensive about loosing too much economy if the performance difference is minimal. . .
You will obtain about +10% acceleration and +10% fuel used.
If you plan to travel at 180-200 kmh I would suggest to don't do it, but if your speed is -for the major part of the time- below 150 kmh (95 mph) you can try.
The point is stock 2.93 makes gear too long for 333 HP.
With 6MT.. I would change ratios of the gearbox (1st, 2nd, 3rd and 4th), but it would be a too expensive job. Or maybe get 3.23 and make the 6th longer. But this is all theory and unfortunately it isn't doable.
Pls let us know on what you'll decide!