Why such small 3.27 gear on L99? Heavy car

[1Camaro2SS]

I really think GM should have put in a bigger gear in these cars. Is the small gear really intended for better gas mileage or what? I mean who wants to drive 150mph anyways? I'd rather have a better 0-60. As heavy as this car is, it can really use a 3.73 by default. What am I missing here?

[SlingShot]

Most would agree with you ...

[Z28RockStar]

I agree, is it the same rear gearing for the manual?

[Camarowguy]

3.45 for manual

[2010 SSRS]

GM should definitely have had different gear options to pick from when we ordered our SS's.

[edneyens]

Originally Posted by 1Camaro2SS

I really think GM should have put in a bigger gear in these cars. Is the small gear really intended for better gas mileage or what? I mean who wants to drive 150mph anyways? I'd rather have a better 0-60. As heavy as this car is, it can really use a 3.73 by default. What am I missing here?

The 3.27 is a good gear for the auto - you really need to take into consideration the transmission gearing. The first gear in the transmission is very low and the combined effect is great for launching. It is true that you could improve quarter mile time slightly by going to a 3.73 but you are not going to gain much...

[thePill]

Good question and I will do my best to explain this.

The L99 Camaro is at a disadvantage, a big disadvantage. With with the gas guzzler tax looming at just 22.5mpg, GM had to take certain steps to ensure that the automatic Camaro didn't fall into the government b@llsh!t. First, active fuel management.. everybody hates it and from what I heard, it can be defeated via aftermarket programing.. not 100% sure though. Second, the extra weight of the 6L80 equipped L99 Camaro is about 53lbs heavier than the LS3 Camaro. I know it isn't much to the regular consumer but I am a weight nazi and 53lbs added to my sports coupe is like adding 53lbs to my wife... I am not a happy camper...

The main reason the final gear ratio is limited in the L99 Camaro is because of the Hydra-matic 6L80 gear ratios. Compared to the TR6060 that the LS3 uses, the gear ratios from 1st gear to 4th are very, very steep. I will lay out the transmission's gear ratios in both the 6L80 and the TR6060 M6.

Hydra-Matic 6l80 six-speed automatic (A6 SS) w/ TAPshift
Gear ratios (:1):
First: 4.03
Second: 2.36
Third: 1.53
Fourth: 1.15
Fifth: 0.85
Sixth: 0.67
Reverse: 3.06
Final drive ratio: 3.27

TR6060 six-speed manual (M6 SS)
Gear ratios (:1):
First: 3.01
Second: 2.07
Third: 1.43
Fourth: 1.00
Fifth: 0.84
Sixth: 0.57
Reverse: 3.28
Final drive ratio: 3.45

As you can see above, the first gear ratio in the 6L80 is a STEEP 4.03. The automatic remains steeper than the TR6060 even up to 4th gear. This would be seen in the drg racing community as a very good transmission.. and it is... If you put a 3.73+ final gear ratio in the 6L80 automatic and make engine adjustments to level the horsepower rating even with the LS3 you would have the potential for some serious 60 foot times. First gear is very aggressive and it is so aggressive that using a 3.45 gear ratio that the LS3 uses would have a very negative effect on fuel economy. With the 6L80 transmission's gearing, the Camaro can achieve similar performance as the LS3 with 26 less horsepower, 10 less foot pounds of torque, 53lbs extra curb weight and 0.18 higher final gear ratio. If GM were to level the L99 and LS3, it is very possible that the fuel efficiency in the L99 would be much lower than the 23 highway rating that it gets now, lowering it into the gas guzzlers 22.5... and costing the consumer $1300 more for the automatic and in turn... making the automatic a very unattractive option and ultimately affecting overall sales.

[1Camaro2SS]

Thepill- great explanation, thank you. I was aware of the gear ration between the manual and auto. I guess it all comes down to better mpg and avoiding the gas guzzler tax. I would love to have a bigger gear in mine. I can use some better 0-60 times. Of course I would need some good tires too to avoid too much spin.

[thePill]

Originally Posted by 1Camaro2SS

Thepill- great explanation, thank you. I was aware of the gear ration between the manual and auto. I guess it all comes down to better mpg and avoiding the gas guzzler tax. I would love to have a bigger gear in mine. I can use some better 0-60 times. Of course I would need some good tires too to avoid too much spin.

GM gave you a better base transmission for drag racing.. period... With light engine modifications and a 3.73-4.10 final gear ratio (don't forget your drag radials) you will be faster than a manual 9 times out of 10.. until you get into the 10.5 bracket (Outlaw class) where automatic's are prohibited..

I have seen the Hydra-Matic 6L80 open and have read a lot about it. It is a fantastic transmission (built by GM).

[ViperTomcat]

Could be worse, I was dealing with a 3.06 in the Challenger

I would have loved 3.15's or 3.27's

[Apex Motorsports]

Originally Posted by thePill

...the gas guzzler tax ... government b@llsh!t ... fuel efficiency ... sales.

This.

[GeorgeM]

The 3.27 gear for the automatics is all about the CAFE standards and advertised fuel economy. The largest numbers on the window sticker on any care are the city/highway MPG estimates, so to produce the higher numbers they have to sacrifice the rear gear.

Keep in mind GM could have reduced the hp to say 375 and offered a numerically higher rear gear, but the hp rating is what sells. Most Camaro owners (except the nominally few who are performance enthusiasts and frequent this site), don't know squat about rear gears.

GeorgeM

[VA-REBEL]

Does any know if the 1LT has the 3.27 gear for the automatics. Chevy website for 1LT indicates 3.27 for the manual.

[b4z]

Keep in mind that the 5th gen Camaro has a wheel/tire package that is almost 3" taller than a 3rd gen, 4th gen or newer GTO.
Also the Corvette with the same engine and transmission comes with a 2.56 or optional 2.93 rear gear ratio.
As others have said the 1st gear in the transmission is super low so you aren't really losing that much when you compare rear gears to other vehicles rear gears. W
When you factor in the tire height the 5th gen is at a bit of a disadvantage on torque mulitplication but at an advantage on hwy crusing rpms.