I'm looking at putting a set of gears in and need advice on which is the best way to go 3.73 or 4.10. my car is an a4 and a daily driver that sees a little track time. I love the idea of a 4.10, but am not sure of the drawbacks. I'd also be interested in what kind of reduction in quarter mile time I'd get with both.

Experts....help a brother out!!!

pmh

 

No more than 3.73's for an auto is all you'll hear on this forum. 4.10's are too much for the highway. If this was strictly a drag car, 4.10's would proly work, but since you drive it alot, 3.73's are about as high as you'll be able to stand. You might search the forum a bit for Torque Converters. It seems the general consesus is to go bigger on the TC before doing gears, especially if you are modding for the 1/4 mile. Typical gains with a TC seem to be around .5 seconds while gears seem to be .1-.2 seconds. That's what I have read here anyway, although someone who has done either of these mods will be able to tell you better. However, I am convinced to do the TC before the gears when the time comes. Most of the guys say a TC with stock gears is the perfect setup. I seem to remember a 3500 TC with 3.23's being a favorite. Something to think about.

 

TC first

 

yup i vote convertor...besides 4.10's make the rear end a time bomb on a stock 10 bolt.

Nate

 

3 :73s!!!!!!!!!!!!!!!!!! But the real gain will be with the TC!

 

Unless you are running a taller tire 3.73 will be fine.

 

ok....I am gonna chime in for the gears. I just changed my 2.73 to a 3.73.... I went from a 13.69 @104.01 to 13.24 @ 107.65 That was without a tire and hitting the rev limiter on the 1-2 shift as well as the 2-3 shift......This weekend I will have that problem fixed and will bolt on a set of nitto's.....I expect nothing less than 13.10 at 108+ or faster. I know I will pick up the short time ( i only went a 2.05 60') It is hard to guess how much time hitting the rev limiter cost me....but it has to be at least a tenth. At the end of the day I should get at least .6 and 4+ mph........Now at the same time a converter is a very good mod for these cars and it will be my next mod. Either way you cant go wrong.Also.....i would say go with the 3.73 over the 4.10 for a daily driver......I have had both.....4.10 is a bit much for a daily driver with an a4......you can do it but it is not worth it....you will get about the same gains from a 3.73 and have a better driving car.......Hope this helps......Good Luck

 

I have 4.10's in my A4. It was my daily driver for 2 years. I had no problems with running it on the highway. It didn't hurt my gas mileage that much either. I say go with 4.10's.

 

I picked up a full 6 tenths and 2 mph going from 3.23 to 4.10

 

if you plan on going with a torque converter, get that first; then get the gears.... I have a buddy that went from 2.73 to 3.73 and then put a 3200 stall, and he is now in the process of putting back a smaller gear.....

 

Jeesh, and you have an a4, with those little gears. I have 4.56's with a th400, and a BBC, that gets driven frequently. However I run a 30x12.50 tire.

 

think about 3.42's and a TC

 

4.10's too much for an A4. I ve driven an A4 from El Paso TX to Roswell NM and it sucked.. I couldnt keep up with my buddies, I was running at 4 grand going 80 mph (maybe exagerating a bit). The damn car kept overheating. So I decided to take mine next time. Drove mine with the 4.10's from Tucson AZ to El Paso TX with no problems. Didnt even feel it. Go 3.73's my friend.

 

Sorry if I'm going off topic here, but what kind of E.T. gain from 3.73's to 4.10's if you already have a big stall? I'm going from a SS4000 to PT4400 and 3.73's to 3.90's. I'm considering going to 4.10's instead since it's not a daily driver.

 

It'll be noticeable as long as your car produces the power where you are in the RPM band


Also NOT ANOTHER ONE OF THESE THREADS! 3.73's are excellent gears for automatics especially with a stock rev limiter. Even so with a raised one for daily driving. 4.10/11's are a bit high for a daily driven vehicle because you'll cruise much higher in the RPM band at a given speed. If you really want streetability id say 3.23's are a minimum and 3.42's will fit nicely. 3.42's are basically better then stock but have little to no difference what so ever. I would go high stall and 3.42's if streetability is a concern and if you have 2.73's otherwise go 3.73's if you have 2.73's. if you have 3.23's KEEP them and get a T/A girdle for your differential youll appreciate it. depending on what kinda daily driving, little to no precipitation get 3500+ and run DR's if its dry/wet get a sub 3500 so id say 3200 tops stall and run dry and wet tires

all in all streetability will never go into the 4's, any 3 will work fine.

JMHO

Adam

 

Thanks for the replies, keep them coming!


pmh