4.11 diff gears?

ILLaViTaR · 05-09-2007, 10:18 PM

I hear a lot of people talking about diffs.

What exactly are they?

Is it another name for the axle or the part in the center that the tailshaft connects to?

I was told 4.11 diff gears were the best value for money mod.

Are there any disadvantages such as transmission strain, worse economy etc?

blur1 · 05-09-2007, 10:25 PM

it is the ratio of the crown and pinion,(geared wheels inside the diff housing centre).it is a lower gear ratio than most std cars.... it is a similar effect to using a big gear wheel on the back of a pushbike compared to a smaller gear wheel. ( hope that kinda explains it.

Melchior3 · 05-09-2007, 11:06 PM

Quote:

Originally Posted by ILLaViTaR

I hear a lot of people talking about diffs.

What exactly are they?

They're the part of the driveline that transfer torque to the axles and hence wheels, through gears (as posted above)

Quote:

Originally Posted by ILLaViTaR

Is it another name for the axle or the part in the center that the tailshaft connects to?

Yep.

Quote:

Originally Posted by ILLaViTaR

I was told 4.11 diff gears were the best value for money mod.

Debateble. It depends what you want.
If you want acceleration, it's a good mod to do as it gives better takeoff, but the car will rev higher also, particularly noticeable when cruising at highway speeds.
It's also worthy to note that if you change your diff gears, you should make sure to get LSD, as 4.11 gears with LSD aren't so great.

Quote:

Originally Posted by ILLaViTaR

Are there any disadvantages such as transmission strain, worse economy etc?

If anything I guess it would be easier on the rest of the driveline as it makes the wheels spin easier? Not 100% sure really, never heard of longevity issues, besides the need to light the wheels up with your newfound ability.

Generally, economy will suffer due to higher revving. If you want to get better takeoff but maintain some cruisability go for something like 3.5-3.9, can't really say without knowing what you have already.

private9 · 05-09-2007, 11:15 PM

Given that practically every thread you start mentions a concern with fuel economy, I really don't think 4.11's would be the best mod for you.

ILLaViTaR · 06-09-2007, 12:04 AM

Quote:

Originally Posted by Melchior3

They're the part of the driveline that transfer torque to the axles and hence wheels, through gears (as posted above)

Yep.

Debateble. It depends what you want.
If you want acceleration, it's a good mod to do as it gives better takeoff, but the car will rev higher also, particularly noticeable when cruising at highway speeds.
It's also worthy to note that if you change your diff gears, you should make sure to get LSD, as 4.11 gears with LSD aren't so great.

If anything I guess it would be easier on the rest of the driveline as it makes the wheels spin easier? Not 100% sure really, never heard of longevity issues, besides the need to light the wheels up with your newfound ability.

Generally, economy will suffer due to higher revving. If you want to get better takeoff but maintain some cruisability go for something like 3.5-3.9, can't really say without knowing what you have already.

Thanks well mine are whatever came stock in the falcons.

I'm guessing though 4.11's won't be as good for towing?

webby_191189 · 06-09-2007, 07:30 AM

It wont be good on economy due to revving higher in the gears because its a higher ratio. Standard will be 3.27 or something like that. If you wanted better economy you would get 2.77 gears. But you loose takeoff power with a ratio like that

**Sorted** · 06-09-2007, 12:18 PM

4.11's are gears for a car that you want to Drag Race

If your car is not a daily and you drive it only on weekends then go for it

If your car is a daily then your going to increase the wear and tear on your car due to it having to rev higher..........

And yes its good for take off but rubbsih for fuel economy

DEVL-XR · 06-09-2007, 02:35 PM

Quote:

Originally Posted by ILLaViTaR

I was told 4.11 diff gears were the best value for money mod.

Do you hear of every mod being the best value for money? I thought you said that you were told a catback exhaust was the best value for money mod?

blur1 · 06-09-2007, 05:00 PM

Quote:

Originally Posted by webby_191189

It wont be good on economy due to revving higher in the gears because its a higher ratio. Standard will be 3.27 or something like that. If you wanted better economy you would get 2.77 gears. But you loose takeoff power with a ratio like that

it's a LOWER ratio. low ratio = fast revving
HIGHER ratio = highway gearing ( slower revving).

feebs · 06-09-2007, 07:14 PM

Probably better off calling it tall and short, not high and low.

Forget about fuel usage, only 35 kms per tank difference for me going from 3.23 to 3.9, and thats at 52km/h average so I do have some high speed driving involved.

If you ONLY do highway driving then you will lose 15% in distance per tank though.

If you also fit a modifed torque converter then you will use more fuel.

Is it the best value mod per dollar?.. at 1200 bucks and 0.5 seconds difference from 0-100.. maybe.. full exhaust is proably still better per dollar, but not as much fun.

webby_191189 · 06-09-2007, 07:41 PM

Quote:

Originally Posted by blur1

it's a LOWER ratio. low ratio = fast revving
HIGHER ratio = highway gearing ( slower revving).

Ahh i always get that the wrong way around lol. Thanks for the correction