Opinions on going from 3.42 to 3.73 ?
03-27-2010, 10:42 PM
#1
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Opinions on going from 3.42 to 3.73 ? I was wondering what you guys thought about going from 3.42 to 3.73 in an M6. This car does not see the track and I don't launch out hard often at all. So I don't think breaking the 10 bolt will be an issue. Just want to be able to get through the gears a little quicker while retaining top end and keeping gas mileage. I'll be putting a rear end cover on along with this and most races are done from a roll. Do you think doing this would be worth the money spent since I won't be doing a 12 bolt till the car is paid off in a couple years. Thanks!
03-27-2010, 10:56 PM
#2
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I know people have done it but IMO just go with 4.10s you will not see a big change in gas mileage. I went from 3.42s to 4.10s and I was so happy i didn't go with 3.73s it was a huge improvement
03-28-2010, 04:17 AM
#3
IMO it would probably cheaper to buy a good used 10 bolt complete rearend with 3.73 gears and swap the whole rearend vs buying gears and paying labor to install and setup new gears in your existing rearend.
It's a waste of money to just swap from 3.42 to 3.73. I doubt you will see more than 200 rpms diff at 70 mph. Save it all for the 12 bolt.
I have an A4 and went from a 3.23 10 bolt to 3.73 Moser 12 bolt and at the same time increased rwhp from 385 to 570 rwhp with an ATI DISC.
Because I don't race I wanted driveability so I went back to 3.42 gears in the Moser. My next lower gear choice would have been 3.08 gears. If I had to do it again I should have installed 3.08 gears instead of the 3.42 gears. I dropped about 200 rpms by switching from 3.73 to 3.42.
3.08 gears would have given me about 1900 rpms at 70 with an A4.
It's a waste of money to just swap from 3.42 to 3.73. I doubt you will see more than 200 rpms diff at 70 mph. Save it all for the 12 bolt.
I have an A4 and went from a 3.23 10 bolt to 3.73 Moser 12 bolt and at the same time increased rwhp from 385 to 570 rwhp with an ATI DISC.
Because I don't race I wanted driveability so I went back to 3.42 gears in the Moser. My next lower gear choice would have been 3.08 gears. If I had to do it again I should have installed 3.08 gears instead of the 3.42 gears. I dropped about 200 rpms by switching from 3.73 to 3.42.
3.08 gears would have given me about 1900 rpms at 70 with an A4.
03-29-2010, 08:42 PM
#6
There are a ridiculous amount of threads about this very question...
Don't waste your time with 3.73s. Go with 4.10s without a doubt. Worried about mileage you say? I got just under 25 mpg with heads/cam/4.10s cruising with the a/c on in hills and mountains at 75-80 mph. That's plenty good IMO.
Don't waste your time with 3.73s. Go with 4.10s without a doubt. Worried about mileage you say? I got just under 25 mpg with heads/cam/4.10s cruising with the a/c on in hills and mountains at 75-80 mph. That's plenty good IMO.
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03-29-2010, 09:32 PM
#8
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