3:43 to 3:73
#2
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Going from 3.42s to 3.73s isn't a significant change. I am assuming you have an m6 although you could have an auto that's already had the gears swapped.
If you have a manual, go with at least 4.10s. Steeper gears will help you get off the line quicker which will give you a quicker et.
If you have a manual, go with at least 4.10s. Steeper gears will help you get off the line quicker which will give you a quicker et.
#3
X2, m6's should be 4.11 from the factory and A4's 3.73.
however i'm going 3.90 when i get a rear.
and a gear swap isnt going to get you much of a gain at all.
when i went from 3.23 to 3.73 in my old car, i gaind .5 mph and like .05 et.
small gains like that are filed under better weather, launch etc etc in my opinion.
however i'm going 3.90 when i get a rear.
and a gear swap isnt going to get you much of a gain at all.
when i went from 3.23 to 3.73 in my old car, i gaind .5 mph and like .05 et.
small gains like that are filed under better weather, launch etc etc in my opinion.
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#9
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My 98 A4 TA came with 3.42 gears from the factory. I went to 3.73 gears and felt a significant difference. Never ran it with the stock gears in it though so I can't say about the actual gains, it just felt better.
#10
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V6 A4's came with 3.23-V8 A4's came with 3.42
I had a 77 Bird with a 455 and 2.41 gears, went to 3.42 and wasted my time doing the work, then I went to 3.73 and was super pleased.
So now you have 2 people saaying that 3.42 to 3.73 is worth it. Ecspecially if you have an A4.
I had a 77 Bird with a 455 and 2.41 gears, went to 3.42 and wasted my time doing the work, then I went to 3.73 and was super pleased.
So now you have 2 people saaying that 3.42 to 3.73 is worth it. Ecspecially if you have an A4.
#16
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Its not difficult to remember, and I dont do V6s so dont ask me about them.
All 4th gen V8s came with:
3.42 if an M6, SS or Z it doesnt matter
3.23 if an auto SS, some Zs got this as well
2.73 if a non SS auto, and didnt get the 3.23 as an option.<---these cares got steel driveshafts, non z rated tires, and no 1st gear selector on the console.
I think the first year M6 Z 4th gen got 3.23 then the very next year they switched/stayed with the 3.42.
All 4th gen V8s came with:
3.42 if an M6, SS or Z it doesnt matter
3.23 if an auto SS, some Zs got this as well
2.73 if a non SS auto, and didnt get the 3.23 as an option.<---these cares got steel driveshafts, non z rated tires, and no 1st gear selector on the console.
I think the first year M6 Z 4th gen got 3.23 then the very next year they switched/stayed with the 3.42.
#17
Did you ever do a read to see what ratio had been programmed into the PCM by the factory?
#18
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The shop that did the rear end has been a rear end only shop for something like 30-40 years and he said "hell they just throw whatever is laying around in em sometimes" which I wouldnt be surprised, or say for instance if they ran out for some reason they may have substituted, just like some F body's ended up with LS6 blocks in them..
#19
Im sure they probably did, and no I didnt BUT I havent had it changed yet to read 3:73's so I will try to remember to do that cause that will be interesting to know. I drove the car 10 miles from the rear end shop to the body shop so when I get it back I will take it to the tuner to change the gear ratio in the computer. I do know that the speedo read properly before though.
The shop that did the rear end has been a rear end only shop for something like 30-40 years and he said "hell they just throw whatever is laying around in em sometimes" which I wouldnt be surprised, or say for instance if they ran out for some reason they may have substituted, just like some F body's ended up with LS6 blocks in them..
The shop that did the rear end has been a rear end only shop for something like 30-40 years and he said "hell they just throw whatever is laying around in em sometimes" which I wouldnt be surprised, or say for instance if they ran out for some reason they may have substituted, just like some F body's ended up with LS6 blocks in them..
If you are not the original owner then I suspect the 3.42 gears possibly found their way into your car via other means - maybe a dealership warranty where the dealership ordered parts, discovered they were wrong but installed them anyway. Can a dealership change the settings in the PCM with a Tech II - to account for the different ratio - I don't know.
What does the label on the door post say for the rearend ratio - 3.23 has a special code as does the 3.42 code?
#20
TECH Veteran
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I doubt seriously that GM took the time to reflash the PCM with all of the parameters to necessary to change the rearend ratio from 3.23 to 3.42. Because they would have had to change the shift points too.
If you are not the original owner then I suspect the 3.42 gears possibly found their way into your car via other means - maybe a dealership warranty where the dealership ordered parts, discovered they were wrong but installed them anyway. Can a dealership change the settings in the PCM with a Tech II - to account for the different ratio - I don't know.
What does the label on the door post say for the rearend ratio - 3.23 has a special code as does the 3.42 code?
If you are not the original owner then I suspect the 3.42 gears possibly found their way into your car via other means - maybe a dealership warranty where the dealership ordered parts, discovered they were wrong but installed them anyway. Can a dealership change the settings in the PCM with a Tech II - to account for the different ratio - I don't know.
What does the label on the door post say for the rearend ratio - 3.23 has a special code as does the 3.42 code?
I wish I knew at what point of assembly the gears are changed in the auto car when the SS option is designated and maybe I could answer your question a little better, but that im aware of SLP does the modifications that change the car from a Z28 to a SS so im kinda under the impression they may have been the ones to do the gear change in which case they would have had to have changed the ratio in the ECU from 2:73 to 3:23 so why would it not be just as easy for them or even chevrolet to program it for 3:42's
In any case there is a seperate tune done by one of them because they have two auto flashes with different gear ratio's. Im sure it wouldn't be difficult for either company to implement a third.
After seeing the gears I am as curious of this as you...
Last edited by 00pooterSS; 12-26-2009 at 11:57 PM.