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3:42 gears, why did GM bother...

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Old Jun 30, 2003 | 12:10 AM
  #16  
ChrisLS1Bird's Avatar
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The ratios are

3.42:1
4.10:1
3.73:1
2.73:1

4:10=0.4:1. The gears are not "0.4's," are they? They are 4.10:1 gears.

: designates a ratio
. is a decimal point

Call them 4.10's, 3.73's, etc. When you put the colon ( : ) in the wrong place, you are changing the ratio.
Old Jul 1, 2003 | 12:41 PM
  #17  
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.....yeah thanks.....its called a typo...I got it right when I said 3.42:1.....
Old Jul 1, 2003 | 12:50 PM
  #18  
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Old Jul 1, 2003 | 01:50 PM
  #19  
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Originally posted by Koors96Z
all stock ls1's have 10 bolt rears, if you have a 6 speed, its 3.42 gears. auto will be 2.73 or 3.23 depending on if you got the performance axle or not. i forgot what rpo code goes with 2.73 and 3.23, im sure someone else knows though.
The 2.73:1 geared cars have the GU2 rpo code on the door.
The 3.23:1 geared cars have the GU4 (i think )
Old Jul 1, 2003 | 04:38 PM
  #20  
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The 3.23:1 geared cars have the GU4 (i think )
It's GU5.

My friend has a '99 Z28 with a 6-speed and my car has the A4 and 3.23 gears. I think GM gave the 6 speed higher gearing in order for it to be just as fast as the 3.23-equipped cars with equal drivers, because no one can shift as fast and precise as a machine can. Just my opinion.
Old Jul 1, 2003 | 06:31 PM
  #21  
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Originally posted by Sparkz28
with 4:10 's and a t-56 5th gear is only good to 130mph...and then you shift into 6th and your slowly crawl to 150mph....if you have enuff road....

with the 3.42's your 4th gear is going to run to the same 130mph.....only when you hit 5th..the car continues to pull hard up to 160mph

you will fall back hard with 4:10's on the top end because you dont make the power needed to pull the .50:1 6th gear ...unless..you have
A.n2o
or
B. a blower or turbo....
First off you can run up to 112mph at 6k in 4th so unless your modding alot (without cam that would raise redline and mph) you will be ok. 3.42's are only good to 103 in third so you will probly shift into 4th or hold out in 3rd when you have more mph to be had. As a general rule you want to be at the end of your powerband in your direct drive gear(4th) when running though the traps. At least this what I read in the drag racing forum.

In 5th gear at 6k you can run 151mph with stock tires. See the f-body gears page .
Get a cam with hardened pushrods and go 6600rpm at 166mph in 5th. Or get taller tires. But maybe I'm the only one who doesn't need to go over 150 enough to use it as an excuse to not get 4.10's though.
Old Jul 1, 2003 | 06:31 PM
  #22  
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A 6-speed with a 3.23 rear would not be able to pull 6th gear anywhere. The 93's that had 3.23 rears and a 6 speed had a 6th gear of .62:1 ratio as oppossed to the .50:1 ratio used from 1994 on.
Old Jul 2, 2003 | 12:51 AM
  #23  
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Originally posted by 99BlackZ28T56
First off you can run up to 112mph at 6k in 4th so unless your modding alot (without cam that would raise redline and mph) you will be ok. 3.42's are only good to 103 in third so you will probly shift into 4th or hold out in 3rd when you have more mph to be had. As a general rule you want to be at the end of your powerband in your direct drive gear(4th) when running though the traps. At least this what I read in the drag racing forum.

In 5th gear at 6k you can run 151mph with stock tires. See the f-body gears page .
Get a cam with hardened pushrods and go 6600rpm at 166mph in 5th. Or get taller tires. But maybe I'm the only one who doesn't need to go over 150 enough to use it as an excuse to not get 4.10's though.
your math is not right...

my laptop reads well over 165 in 5th @6,000 rpms

......... 6600 rpms in 5th with the stock gears and a t-56 is 195mph....with the stock size tire....
Old Jul 2, 2003 | 01:35 AM
  #24  
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personally i like 3.42s....

im getting rid of the dead 2.73s in my car in the next couple weeks and im gonna switch to 3.42....3.23 is good but 3.42 is a bit better and 3.73 may be too much form some people (like me) because i need (my only car) to get some semblance of respectable gas mileage (gonna be pretty difficult with 3.42s and a 3200 stall) so 3.42 is a good choice IMO..
Old Jul 2, 2003 | 02:10 AM
  #25  
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anybody have any links on how to install gears? is this something the average joe coudl do or shoudl u take it to a mechanic?
Old Jul 2, 2003 | 03:15 AM
  #26  
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DEFINITELY take it to a mechanic. Setting up gears properly is tough to do...and if you **** up just a little, they whine loudly and/or break.

I'm going to install some 3:73s...I need some serious overdrive. Gas prices are high. Hopefully, I'll turn about 900 rpm at 160 mph in 3rd gear.
Old Jul 2, 2003 | 08:58 AM
  #27  
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3.73s

I have a brand new set of GM 3:73s that I cannot afford to put in this year if anyone wants them. I'd like to get 200 plus shipping for them; is this reasonable? Or perhaps some trading would be in order.
Old Jul 2, 2003 | 03:21 PM
  #28  
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Originally posted by SFB767
It's GU5.

My friend has a '99 Z28 with a 6-speed and my car has the A4 and 3.23 gears. I think GM gave the 6 speed higher gearing in order for it to be just as fast as the 3.23-equipped cars with equal drivers, because no one can shift as fast and precise as a machine can. Just my opinion.
you might be surprised at how fast a good driver can shift. Also i beleive they game them the 3.42 because they have 6 speeds instread of 4 so they could aford to give it 3.42 and still get descent gas milage and such.
Old Jul 2, 2003 | 06:24 PM
  #29  
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..... not as fast as an built auto thats for sure......I know that one time in car and driver the test the speed of Mario Andretti's shift....and it was .2 of a second from clutch in to clutch out.....thats damn fast..and thats a little slower then a built auto....
Old Jul 2, 2003 | 08:56 PM
  #30  
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ehh, who cares? M6s put more power to the ground. Take pride in the fast shifting while the M6 pulls away while in gear.

111 mph with just a lid, catback, and free mods.

I think GM gave the 6 speed higher gearing in order for it to be just as fast as the 3.23-equipped cars with equal drivers, because no one can shift as fast and precise as a machine can.
LOL! Let's not consider HP and the actual gear ratios of the transmissions. A4s and M6s have exactly the same 1st, 2nd, 3rd, and 4th gears...huh? Nice rationalization...I'm going to share it with my friends.



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