3.73 vs 3.91 gears in an SS A6

[lexlueger]

3.91 on a supercharged auto, fun..yes, practical NO. Useless first gear and high cruising rpms.

[mike.nite]

So it seems like 3.73 is the way to go on the A6 if you want to keep drivability.

[mike.nite]

Is there a big difference from stock (L99) to 3.70s ?

[Kyle2k]

Originally Posted by mike.nite

Is there a big difference from stock (L99) to 3.70s ?

It will be like having ~ 60 more ft-lbs of torque if you are stock so yeah.

[AC]

I have 3.73's with an A6 and love them....my opinion is any lower is too much for the A6. First gear is almost useless for everyday driving but exactly what I needed for the launch at the track. Highway rpm's will be about 300 more so still good for road trips. I probably would have gone with the LPE 3.91 if they were cheaper but glad I did not. If you go Richmond make sure you have them polished. It will make them as quiet as stock and properly installed you will have no problems.

[SGOS252382]

Originally Posted by Kyle2k

It will be like having ~ 60 more ft-lbs of torque if you are stock so yeah.

That's what they always say based on calculations.

Add 60 ft lbs of torque to one Camaro SS and have it race a different Camaro SS with just 3:73 gears and see who wins.

[Kyle2k]

Originally Posted by SGOS252382

That's what they always say based on calculations.

Add 60 ft lbs of torque to one Camaro SS and have it race a different Camaro SS with just 3:73 gears and see who wins.

I'm basing it on math and the different ratios, it is the most objective way at looking at it. Clarify for the OP what you are getting at? Were you disappointed with the upgrade or what?

[Fiftydriver]

Originally Posted by lexlueger

3.91 on a supercharged auto, fun..yes, practical NO. Useless first gear and high cruising rpms.

I am running 2300 rpms at 70 mph, with the 3.73 gears I was running around 2150 rpms and with the factory gears I was in the 2050 rpm range. For the added fun factor and more torque to the ground, adding 250 rpms at highway speeds is not a big deal.

I can cruise at 80 mph and still be under 2500 rpms.

Its not that big of a deal. As mentioned, the A6 had very aggressive 1 and 2 gear ratios but it also has very high 5 and 6th gears.

As far as first gear for street driving, unless your mashing the throttle all the time, it works just fine, even with a supercharger. The trick is that you just do not have to hit the throttle as hard to get moving!!! LOL My car is as streetable as a stock A6. Only gets wild if you want it to get that way.

I also see your running a torque converter which I was strongly advised to not go with a TC for street use with these gears and the supercharger because there is no need to raise your RPM levels at take off. The Maggie puts you right there for power right off idle anyway so I would say your TC is likely what would make you feel the 3.91s are to much. Without one, yes 3.91s are alot of gear but its totally practical for street use.

[E.T.]

Originally Posted by Kyle2k

It will be like having ~ 60 more ft-lbs of torque if you are stock so yeah.

Yep, gears are just a TQ multiplier. There aren't many mods that will give you that amount of TQ increase. More importantly, it's at the wheels.

[mike.nite]

Originally Posted by E.T.

Yep, gears are just a TQ multiplier. There aren't many mods that will give you that amount of TQ increase. More importantly, it's at the wheels.

Thanks for chiming in E.T.!
Did you notice a big difference? Did you ever consider going with 3.90?

[E.T.]

Originally Posted by mike.nite

Thanks for chiming in E.T.!
Did you notice a big difference? Did you ever consider going with 3.90?

Here's my thread on 'em:

http://www.camaro5.com/forums/showthread.php?t=213951

In short, I love them. I picked up the car today and put some miles on it driving around town. Taking it fairly easy as they break in, but it's a very noticeable difference.

I did a lot of reading on here, and everyone usually says 3.70 or 3.73 is perfect for the auto, and 4.10s are good for the manual. Not sure if 3.90s would be overdoing it? First gear is fine now, but it doesn't take much pedal from a stop to get her going. I haven't got on it very hard from a stop yet, but there might be some traction issues even with the 3.70s. It's definitely fine as a DD, but you just have to be gentle with the throttle. Also, 6th gear feels much stronger at highway speeds. I'm extremely happy with these so far

[Rhino79]

1-4 are very steep as far as tranny gearing on the 6l80, heck 4th is like 1.15 to 1 or something like that. 3.91s would be overkill for the a6. M6 guys run them because their transmission gearing is less aggressive than the a6. a 3.91 in a stick car will be very closely geared to what a 3.73 would be in an a6. And for boost, I'd look for 3.45s for the a6, boost likes higher gearing because the tq is so monsterous.

[mike.nite]

Originally Posted by Rhino79

1-4 are very steep as far as tranny gearing on the 6l80, heck 4th is like 1.15 to 1 or something like that. 3.91s would be overkill for the a6. M6 guys run them because their transmission gearing is less aggressive than the a6. a 3.91 in a stick car will be very closely geared to what a 3.73 would be in an a6. And for boost, I'd look for 3.45s for the a6, boost likes higher gearing because the tq is so monsterous.

Thanks Rhino for this explanation. This gives me a good idea when comparing the 3.73 to the 3.91.

[Unobtainium]

I'd say most have never driven an auto with wild gears. They are a blast.
There is no real problem with having a bunch of gear. You will accelerate faster, and with the ridiculous 6th in the auto, cruising should still be great.
I want 6th to be my top speed gear, so I'm thinking the 3.91's are almost enough. You are spending a pile of money doing this, do as much gear changes you dare. You should really drive one with 4.10's or 3.91's before you decide.
The fun factor is huge.