bissett

Do any of the new A6 owners have any experience with the old A4 with the performance rear axle to tell us which is faster?I want to order an 06 but want to know if it's faster than my 05 auto Z51.Thanks

ProfMoriarty

Many of us are awaiting A6 owners to break the 500 mi break-in point so they can get some times.

While there's more to a sports car than 0-60 times, I sure am curious!

The Garage Master

I thought since the A-4 has a better gear it will be faster in the 0-60.

AMF

What is a "better gear"?

The Garage Master

3.15 verse 2.73 I believe. The lower the gear (higher number) the faster off the line less top end.

AMF

2.53 on the A6 I believe. I know 1st gear is lower (final drive) than the 3.15 A4.

C5 then C6

Since I bought the A4, the A6 will be faster!

Braced

I talked to a guy the other day when I was in Oklahoma City who has owned an 05 C6 A4 and now has a 06 A6 paddle shift coupe. He said that the new A6 was significantly quicker than the A4. He ought to know, he's had both. He also had the GM chrome wheel package. I thought they delayed that until next year? But he had them on his C6, I saw them! They looked great! Each wheel had a "corvette" in red lettering on one spoke of the wheel. He also had his center caps painted VY to match the car. The car looked fantastic!

AMF

Isn't that the way it goes? But really, how many times will the average A4 be racing the average A6?

AMF

How in the world could he have gotten the wheels???

aero400

There have been some good threads on this here already. Do a search.

Bottom line, it's the final drive gear multiples that count, not the tranny gear ratios themselves. Multiply the given tranny gear ratio by the rear axle gear ratio to get your final drive gear multiple. The greater the multiple, the more torque available at given speed.

Example... if the first gear in a given tranny is 3:00:1 and the rear end ratio is 3:00:1, the multiple is 9.0. But if the first gear in the tranny is 3.30:1 (which would initially SEEM better), but the REAR END ratio is 2.50:1, the multiple is only 8.25, less available torque to the wheels as in the first example.

I am more curious about the amount of parasitic power consumption of these auto trannies in general verses the manual tranny. I once read somewhere that the average auto transmission, due to the torque converter etc, actually consumes over 10% of your power output verses a manual. Not sure if this is true, would love to know. Also wondering about the weight of the A6 verses the manual as well.

If you know how to shift well, I believe a manual will always be the fastest. But a good light auto tranny that is calibrated REALLY well might be pretty darned fast too! I guess well find out soon once the A6 owners start putting them to the test.

Devils Elbow

If you do the math (overall reduction) with the transmission gear ratios and the final drive, first gear in the A6 works out about equal to first in the mn6 with a 3.90 rear end. 6th gear works out equivalent to 6th in an mn6 with the 3:42 rear end.

Deep Silver C6 Z51

My A4 Z51 is probably the fastest Corvette I will ever own.

No real need to switch unless a rich aunt leaves me some Z06 money.

aero400

We should just create a gear multiple chart for all three trannies (MN6, A4, A6) and post this info in the FAQ so it is easy to compare.

I always wondered if it was fair to directly compare gear multiples of auto trannies against manual trannies because remember, the auto tranny has a torque converter which effectively multiplies torque itself. In order to truly compare side by side, we have to assume that the torque converter is locked.

Ultimately, the auto tranny can have lower multiples and the torque converter will make up for the lost multiplication to some extent depending on how much it slips. But I have read that there is some type of parasitic loss when the torque converter is slipping, so... still a little confused by this.

UncleRobb

I think that there are torque converters that do exactly what the name says: they are able to increase the torque. However, I don't think that the ones used in cars are usually of this type. The ones used in automatic transmissions are rather hydraulic clutches that transmit (at most) the torque they are driven with and, at a cirtain speed, they stall and there is no (or very little) slip. However, compared to clutches used with manual transmissions, the "torque converters" withstand more abuse, that is, slipping. Thus, automatic transmissions do not need the slow first gear that is usually found in manual transmissions.

Tell me if I'm wrong.

My 2 cents, Robert

ProfMoriarty

Just as a point of clarification, the performance axle (no longer available) that could be mated to the A4 was 3.15

The only axle available for the A6 is 2.56

However, the gearing of the A6 is such that the products of gears and axle are greater than the A4 with the 3.15 axle.

RandyMi

I would never **** on a fellow Vette brother, but it is rewarding to know that the new tranny is a step in a positive direction. Lets be positive and wait, in due time we will know. In a past thread the new A6 has a higher first gear and with the multiplication it has a higher number then the A4.

ProfMoriarty

All the A6 non-OD gears are higher than the A4's.

All the A6 gear/axle products are higher than the A4's with the 3.15 axle.

Dennis Dick

The very fastest Corvettes I've seen on a drag strip have had their manual removed and installed automatics. It appears that to get a manual off the line really fast you have to abuse it more than I would care to do to my car. I have a manual because that is what I like to drive. Unless your only thing is racing, get what you will enjoy driving. Now there is my 2 cents.
Dennis

Another Yellow

That is absolutely not true. They are very close according to Team Corvette members who actually tested the cars side by side. Depending on the speed of the car when the auto kicks down to a lower gear, sometimes the edge goes to the A4 and sometimes it goes to the A6. From a dead stop, it depends on the speed you accelerate to. 0 to 30 is quicker with one while 0 to 40 is quicker with the other. Same with 0 to 60 and 0 to 70 and any other combination you might do.

Frank