Gears & Axles Driveshafts | Rearends | Differentials | Gears | 12 Bolt | 9 Inch | Dana

A4 with 3.73's

Thread Tools
 
Search this Thread
 
Old 11-02-2008, 02:23 PM
  #1  
12 Second Club
Thread Starter
iTrader: (9)
 
fly pantera's Avatar
 
Join Date: Jun 2006
Location: SanMarcos,TX
Posts: 624
Received 2 Likes on 1 Post

Default A4 with 3.73's

alright guys im thinking of doing 3.73 in a a4 02 z28.last week it ran a 12.48@112.36 with a 1.98' on 2.73 gears.stock stall

1.how much et can I drop with a gear swap/mph

2.are you happy with your 3.73's if you could pick a gear again what would it be.

3.how long did your 10 bolt last.what kind of 60'.is it holding up or did it break.

thanx guys let me know the good,bad,and the ugly
Old 11-02-2008, 02:49 PM
  #2  
Staging Lane
iTrader: (3)
 
Havok956's Avatar
 
Join Date: Jul 2007
Location: Leander, TX
Posts: 96
Likes: 0
Received 0 Likes on 0 Posts
Default

Jusy had mine installed about two weeks ago. Haven't taken it to track yet but it feels a lot quicker down low. Very hard to find any traction tho with my set up. I'd do it if I were you. I came from 2.73 also and I didn't like them at all
Old 11-02-2008, 02:51 PM
  #3  
TECH Senior Member
iTrader: (5)
 
TXZ28LS1's Avatar
 
Join Date: Mar 2004
Location: Classified
Posts: 6,164
Likes: 0
Received 1 Like on 1 Post

Default

i swapped out my 2.73 to 3.73. but i also did a 3200 stall, and a cam. it definitely woke up the car big time. i think alot of guys will tell you 3.73 are the way to go with an A4. i think the 10 bolt will hold up for awhile from what i have always read on 10 bolts in autos. just as long as you dont put slicks and stuff like that.
Old 11-02-2008, 06:31 PM
  #4  
12 Second Club
Thread Starter
iTrader: (9)
 
fly pantera's Avatar
 
Join Date: Jun 2006
Location: SanMarcos,TX
Posts: 624
Received 2 Likes on 1 Post

Default

3.73's seem like a all around good gear for me,I plan on trapping 127mph on a 150 shot.Right now I want to hit 115mph stock internal.

any reason not to put 3.73,maybe go with 3.42?
Old 11-04-2008, 10:20 AM
  #5  
12 Second Club
Thread Starter
iTrader: (9)
 
fly pantera's Avatar
 
Join Date: Jun 2006
Location: SanMarcos,TX
Posts: 624
Received 2 Likes on 1 Post

Default

anyone else?
Old 11-04-2008, 12:29 PM
  #6  
10 Second Club
iTrader: (4)
 
GMMillwright's Avatar
 
Join Date: Mar 2006
Location: Fort Wayne, IN
Posts: 608
Likes: 0
Received 0 Likes on 0 Posts

Default

I've got 3.73s in my 10 bolt. Had a 1.50 60 foot time last month. I run a 28 inch M&H DR, though. Trapped 137. I lock my TC in top gear which knocks the rpm down. I go through the lights @ 6000, I think. I don't watch the tach @ 137 mph
Old 11-07-2008, 12:00 PM
  #7  
TECH Apprentice
iTrader: (7)
 
yeller_xtc's Avatar
 
Join Date: Jan 2008
Location: rockmart, for now...
Posts: 345
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by fly pantera
3.73's seem like a all around good gear for me,I plan on trapping 127mph on a 150 shot.Right now I want to hit 115mph stock internal.

any reason not to put 3.73,maybe go with 3.42?
im going with 3.42 cause my car sees the expressway often.
Old 11-07-2008, 02:17 PM
  #8  
TECH Addict
iTrader: (3)
 
WS6 Rampage's Avatar
 
Join Date: Feb 2006
Location: The dirty taint of the country. ...Los Angeles
Posts: 2,498
Likes: 0
Received 3 Likes on 2 Posts

Default

3.73 is a good ratio for an automatic.
Old 11-07-2008, 03:21 PM
  #9  
Banned
iTrader: (12)
 
Elliott's94Z's Avatar
 
Join Date: Mar 2008
Location: Oregon Grown
Posts: 4,370
Likes: 0
Received 1 Like on 1 Post
Default

Love my GM 3.73's! Great upgrade!
Old 11-07-2008, 03:35 PM
  #10  
TECH Fanatic
iTrader: (10)
 
omcar's Avatar
 
Join Date: Jun 2006
Location: Pennsylvania
Posts: 1,333
Likes: 0
Received 0 Likes on 0 Posts
Default

good choice..see my sig.
Old 11-07-2008, 04:14 PM
  #11  
Staging Lane
 
OEM_TA's Avatar
 
Join Date: Jun 2008
Location: A bit south of Sacramento, CA
Posts: 60
Likes: 0
Received 0 Likes on 0 Posts
Default

Unless you use the car just for the track or the track and in town driving you will be much happier going with a 3.42. Sustained highway speeds with a 3.73 is not pleasant, I went from 2.73 to 3.73 and less than a month later went to the 3.42. Much happier now.
Old 11-07-2008, 04:26 PM
  #12  
Banned
iTrader: (12)
 
Elliott's94Z's Avatar
 
Join Date: Mar 2008
Location: Oregon Grown
Posts: 4,370
Likes: 0
Received 1 Like on 1 Post
Default

Originally Posted by OEM_TA
Unless you use the car just for the track or the track and in town driving you will be much happier going with a 3.42. Sustained highway speeds with a 3.73 is not pleasant, I went from 2.73 to 3.73 and less than a month later went to the 3.42. Much happier now.
3.73 on the hwy are not that bad. I drive a lot of hwy miles during the summer and it's not bad at all. I would say if you drive a butt load of hwy to go 3.42. If it's more track/around town and hwy every so often 3.73 without a doubt.

Last edited by Elliott's94Z; 11-07-2008 at 04:47 PM.
Old 11-07-2008, 05:12 PM
  #13  
TECH Addict
iTrader: (3)
 
WS6 Rampage's Avatar
 
Join Date: Feb 2006
Location: The dirty taint of the country. ...Los Angeles
Posts: 2,498
Likes: 0
Received 3 Likes on 2 Posts

Default

I always figured that gears were fine but the only thing that makes hwy driving unpleasant if you do allot of it is a high stall. .... I.E.: 4000 stall
Old 11-07-2008, 11:03 PM
  #14  
10 Second Club
iTrader: (4)
 
GMMillwright's Avatar
 
Join Date: Mar 2006
Location: Fort Wayne, IN
Posts: 608
Likes: 0
Received 0 Likes on 0 Posts

Default

If you're worried about highway rpm, just get taller tires. I run 70 mph @ 2000, give or take with my 28s and 3.73s. I even get 20 mpg on the highway.
Old 11-08-2008, 07:25 AM
  #15  
Staging Lane
iTrader: (3)
 
Cowboy97's Avatar
 
Join Date: Oct 2008
Location: Bridge City, TX
Posts: 95
Likes: 0
Received 0 Likes on 0 Posts

Default

I'm going to put 3.73s in mine next week. Just bought the car and one of the bearings in the rearend is making noise, so that was all the reason I needed. The difference between a 3.73 and a 3.42 is probably only like 200 rpm at highway speeds. I know I changed the gear in my 4x4 this summer and went back and forth on it and decided with a 4.56 and my tires measure like 33.5(suppose to be 35). So other than the traction I don't see anything wrong with the gear because these motors love rpms.
Old 11-08-2008, 08:29 AM
  #16  
12 Second Club
 
john shea's Avatar
 
Join Date: May 2004
Location: hazelwood,Mo.
Posts: 656
Likes: 0
Received 0 Likes on 0 Posts
Default

I like my 3.73 gears. I daily drive my car on the highway.
You should pick up .2 to.3 in the 1/4.
Old 11-08-2008, 07:43 PM
  #17  
10 Second Club
iTrader: (40)
 
BOLO's Avatar
 
Join Date: Nov 2006
Location: Mundelein,Illinois
Posts: 3,180
Likes: 0
Received 2 Likes on 2 Posts

Default

3.73 gear is ideal for A4 street/strip. Stoplight to stoplight, 4.10's. in my opinion.
Old 11-08-2008, 09:04 PM
  #18  
TECH Fanatic
iTrader: (4)
 
Blk_Ws6's Avatar
 
Join Date: Feb 2008
Location: In my Science Lab .
Posts: 1,056
Received 0 Likes on 0 Posts

Default

what would you pick up going with 3.42' from 2.73 ?
Old 11-09-2008, 12:46 PM
  #19  
12 Second Club
Thread Starter
iTrader: (9)
 
fly pantera's Avatar
 
Join Date: Jun 2006
Location: SanMarcos,TX
Posts: 624
Received 2 Likes on 1 Post

Default

the car rarely sees the highway,but when it does its only like 30miles.im leaning towards the 3.73.

thanks for all the opinions
Old 11-09-2008, 12:49 PM
  #20  
TECH Fanatic
iTrader: (2)
 
Slvr00Bird's Avatar
 
Join Date: Jan 2007
Location: Ashland & Lexington, KY
Posts: 1,419
Likes: 0
Received 0 Likes on 0 Posts
Default

I have 3.73's and they're great.. actually thought about bumping up to 3.90's when I rear end swap but kind of decided against it.

I'd almost just tell you to save the money and put it in your new rear end fund. The 10 bolt isn't much but an oversized paper weight IMHO. So throwing money into it for temporary fun isn't solving the long term problem of an inferior part. But it's your decision and you have to pay to play either way..


Quick Reply: A4 with 3.73's



All times are GMT -5. The time now is 01:02 AM.