3.90 Rear
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Pro
Joined: May 2006
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From: New York
3.90 Rear
How much increased SOTP can I expect from switching from 3.23 rear to 3.90 ? I have a '04 A4 LS1 with Corsa Cat Backs, K&N aftermarket intake. I'm also planning on a COW tune. Thanks for the help!
Le Mans Master
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From: AKA Harvey Mushman-I know just enough to be dangerous "Those who sacrifice liberty for safety deserve neither"- B. Franklin
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Most A4 guys say to go to 3:42s. I've seen plenty of threads stating that 3:90s are too much without the MN6s 2 OD gears.
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From: ~The DARKSIDE Group~
I have 3.90's in my '04 M6, one of the best mods I've done.
If you are consideing a gear swap also consider a hardened out-put shaft install while you are making the change. The shaft is the weak link in the drive train, if you mod your ride and hook up well on the street or track the shaft is the 1st thing to go.
Good luck in your gear swap decesion, let us know how you go.
If you are consideing a gear swap also consider a hardened out-put shaft install while you are making the change. The shaft is the weak link in the drive train, if you mod your ride and hook up well on the street or track the shaft is the 1st thing to go.
Good luck in your gear swap decesion, let us know how you go.
Instructor
Joined: May 2000
Posts: 195
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From: Augusta Maine
[QUOTE=Dark-Knight]I have 3.90's in my '04 M6, one of the best mods I've done.
If you are consideing a gear swap also consider a hardened out-put shaft install while you are making the change. The shaft is the weak link in the drive train, if you mod your ride and hook up well on the street or track the shaft is the 1st thing to go.
I would only do the 390 with the M6. Would be to much for the
A4, I think.
If you are consideing a gear swap also consider a hardened out-put shaft install while you are making the change. The shaft is the weak link in the drive train, if you mod your ride and hook up well on the street or track the shaft is the 1st thing to go.
I would only do the 390 with the M6. Would be to much for the
A4, I think.
Melting Slicks
Joined: Sep 2005
Posts: 2,625
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From: Rhode Island
I'm going with the 3:42's. Seems to be the best all around setup. I think 3:90's are too much gear for an A4. Even 3:73's are too much. Some drag racers I spoke with are going back to the 3:42's because they lost a few MPH on their trap times. Just my opinion.
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From: Whippany NJ
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St. Jude Donor '08-'09
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Originally Posted by Vette'n04
I meant the 3.15's.....sorry! Will it be worth the $ swapping gears?
I have 4.10s in my MN6 and im glad i went with it despite people here saying its too much. I still get 31 mpg highway.
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From: New York
The concensus seems to be 3:73's with my A4 then right? Do I still need the hardened input shaft then? Also, is the swap from 3:15's to 3:73's worth the $ in overall acceleration improvements during low end and mid-range? Thanks again guys for all the help and inputs!!!!!! 
Le Mans Master
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From: AKA Harvey Mushman-I know just enough to be dangerous "Those who sacrifice liberty for safety deserve neither"- B. Franklin
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Where are you located? I thought you posted in another thread that it is somewhere in NY. If you're near NYC you might be able to get a ride in a few cars that already have the gears you'd like. There seems to be quite a few modded C5s down there.
Melting Slicks
Joined: Apr 2002
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From: louisville ky
Cruise-In VII Veteran
Originally Posted by chargedc5
I have a 2000 a4 with 2.73, is it worth the money going to 3.42's or should i just put in a different stall converter.
Melting Slicks
Joined: Apr 2002
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I think the t/c has a TON to do with how the car will run with steeper gearing. I have an SS3600 and went with 3.42's.... In hindsight, I should have installed 3.73's with this t/c. ORRRR, go with a stall closer to 2600 - 3000 rpm. Just my opinion, the car is a MONSTER on the track @ launch time, but around town driving can be frustrating when going 30 mph up a hill @ damned near 3,000 rpms. UGH!!!
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From: New York
Thats exactly what I don't want! I want the car to be TOTALLY driveable like it is now in the real world, but with more SOTP acceleration when I decide to punch it whether it be from a complete stop or 30 MPH.
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From: Sterling VA
Originally Posted by Ikester
if your not going to do forced induction like supercharger, 3.73 is pefect!
I have 4.10s in my MN6 and im glad i went with it despite people here saying its too much. I still get 31 mpg highway.
I have 4.10s in my MN6 and im glad i went with it despite people here saying its too much. I still get 31 mpg highway.