3.42 vs. 3.73 in an A4
02-22-2003, 10:52 PM
#1
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Join Date: Jun 2002
Location: Aiken, South Carolina
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3.42 vs. 3.73 in an A4
Ok, what is the real deal on 3.42 gears as opposed to 3.73s in an A4.
I hear 3.42 are the best gears for a 3.8 V6 A4
I also hear that 3.73s are too high for a 3.8 V6 A4 because you will be so high in the RPMs in 4th gear when you cross the 1/4 mark.
Whats the best gear for a 3.8 A4
I hear 3.42 are the best gears for a 3.8 V6 A4
I also hear that 3.73s are too high for a 3.8 V6 A4 because you will be so high in the RPMs in 4th gear when you cross the 1/4 mark.
Whats the best gear for a 3.8 A4
02-22-2003, 10:57 PM
#2
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Join Date: May 2002
Location: san anto, tx
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there is nothing wrong with 3.73s. 3.42s are just more ideal for street driving.
with my 3.73s i cruise 70 mph at 2500 rpms. with my old 3.42 i would cruise 70 mph just under 2000 rpms.
get the 3.73s if you drag, if you dont, then dont bother. but since i somewhat know your car-get the 3.73s. http://www.gearsareus.com
with my 3.73s i cruise 70 mph at 2500 rpms. with my old 3.42 i would cruise 70 mph just under 2000 rpms.
get the 3.73s if you drag, if you dont, then dont bother. but since i somewhat know your car-get the 3.73s. http://www.gearsareus.com
02-23-2003, 11:58 AM
#4
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Location: Corpus Christi, TX USA
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i have 3.42's and i cruise at 70 at about 2800 rpm. i like them. it's even funnier when i race my friend in his a4 with 3.08's. i always get the jump off the line. i think 3.42's are good for street and possibly even track. dont lose much top end but good down low.
02-23-2003, 03:16 PM
#6
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Using an RPM calculator for a set of 3.73's on a 4L60-E Tranny with a 26.1 inch tire diamter (stock 235/55/16's) I came up with 2,500 RPM at 71 MPH, before the lockup converter kicks in (drops it about 500 more RPM). So with a 4L60-E 1FastV6 is right on, you should be banking 2000 RPM in cruising.
KillerJello, there is something wrong - you are cruising around in 3rd gear with no overdrive!!! Get your tranny checked!
I wish people would ask before assuming that "BIG" gears kill your top end. That's such BS. Ever used a gear calculator and you'd know that even if you ran 4.56's you'd still have a max top end of 130 MPH, even though the stock computer will only let you hit 115 without editing.
Another thing I have found is that people who complain about top end, never use it. I frequently bang the govenor and I'm running the stock 3.23's.
Its really no suprise that people hear something and then run off with it though, so, I guess I have to be patient with folks and take it in stride. But suffice it to say yes, big gears do take away some of your top end, but not all. And when do most people actually get the chance to go anywhere near their top end anyway? Down in Texas we are fortunate to have some long straight away's. But anyhoo. Hey, if you think big gears kill top end, look at NASCAR. 6.00 minimum gearing and they run 180-200 MPH.
3.23 and 3.42 are not really the end all/be all of street driving - they are a start. 3.73's are what you want if you are an enthusiast. Especially with having an overdrive gear. Jeez. Back in the day we use to cruise 4.11's with only a 1:1 gear. 55 MPH at 3,000 RPM!!! Now that's hardcore.
Lastly, Josh, 3.73's are perfect - like 1FastV6 said. But you won't be crossing the finish line in 4th gear. You'll be crossing the finish line between 3,000 and 3,500 RPM in third gear. You never use the overdrive on the track. But your car isn't even fast enough to worry about that.
In fact, with stock 3.23's there is a good chance you could cross the finish line in 2nd gear!!!
If you are want max acceleration, you want to be just a hair under redline in 3rd gear at the end of the track. And for that, you'd need 4.11's or 4.56's depending on your tire setup.
KillerJello, there is something wrong - you are cruising around in 3rd gear with no overdrive!!! Get your tranny checked!
I wish people would ask before assuming that "BIG" gears kill your top end. That's such BS. Ever used a gear calculator and you'd know that even if you ran 4.56's you'd still have a max top end of 130 MPH, even though the stock computer will only let you hit 115 without editing.
Another thing I have found is that people who complain about top end, never use it. I frequently bang the govenor and I'm running the stock 3.23's.
Its really no suprise that people hear something and then run off with it though, so, I guess I have to be patient with folks and take it in stride. But suffice it to say yes, big gears do take away some of your top end, but not all. And when do most people actually get the chance to go anywhere near their top end anyway? Down in Texas we are fortunate to have some long straight away's. But anyhoo. Hey, if you think big gears kill top end, look at NASCAR. 6.00 minimum gearing and they run 180-200 MPH.
3.23 and 3.42 are not really the end all/be all of street driving - they are a start. 3.73's are what you want if you are an enthusiast. Especially with having an overdrive gear. Jeez. Back in the day we use to cruise 4.11's with only a 1:1 gear. 55 MPH at 3,000 RPM!!! Now that's hardcore.
Lastly, Josh, 3.73's are perfect - like 1FastV6 said. But you won't be crossing the finish line in 4th gear. You'll be crossing the finish line between 3,000 and 3,500 RPM in third gear. You never use the overdrive on the track. But your car isn't even fast enough to worry about that.
In fact, with stock 3.23's there is a good chance you could cross the finish line in 2nd gear!!!
If you are want max acceleration, you want to be just a hair under redline in 3rd gear at the end of the track. And for that, you'd need 4.11's or 4.56's depending on your tire setup.
02-23-2003, 04:29 PM
#7
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Join Date: May 2002
Location: san anto, tx
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thanks blig, i knew i was right. i look at my rpms and mph all the time. as well as oil pressure and temperature and everything else. i know my car better than i know my own girlfriend. and lately my car has been ****ing me even more than her.
uh oh. Sounds like trouble on the home front? tee-hee-hee. 
02-24-2003, 09:00 AM
#11
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Location: san anto, tx
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i say get the 3.73s but then your speedo will be off. fixable though.
i just cruised 60 miles checking the rpms and mph relationship.
55 mph--1900 rpms
70 mph-- 2400 rpms
75 mph-- dead on 2500 rpms
80 mph- 2800 rpms
and all of these where cruising for miles at a time.
i just cruised 60 miles checking the rpms and mph relationship.
55 mph--1900 rpms
70 mph-- 2400 rpms
75 mph-- dead on 2500 rpms
80 mph- 2800 rpms
and all of these where cruising for miles at a time.
02-25-2003, 07:35 PM
#13
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Join Date: Mar 2001
Location: TX Med Ctr
Posts: 4,000
Originally posted by Bliggida
Using an RPM calculator for a set of 3.73's on a 4L60-E Tranny with a 26.1 inch tire diamter (stock 235/55/16's) I came up with 2,500 RPM at 71 MPH, before the lockup converter kicks in (drops it about 500 more RPM). So with a 4L60-E 1FastV6 is right on, you should be banking 2000 RPM in cruising.
Using an RPM calculator for a set of 3.73's on a 4L60-E Tranny with a 26.1 inch tire diamter (stock 235/55/16's) I came up with 2,500 RPM at 71 MPH, before the lockup converter kicks in (drops it about 500 more RPM). So with a 4L60-E 1FastV6 is right on, you should be banking 2000 RPM in cruising.
EDIT: it's 2580 @70mph w/ 4.10's
EDIT AGAIN:
Since I did this in Excel and it is so easy to add more gears...
At 70mph, for the 4L60E (4th Gear = 0.70):
Gears----RPM
2.73------1718
3.08------1938
3.23------2032
3.42------2152
3.73------2347
4.10------2580
4.56------2869
Last edited by HAZ-Matt; 02-25-2003 at 07:46 PM.
