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Aren Jay
05-11-2008, 03:34 PM
Everyone talks about going to a 4.10 rear end but what i want to know is what is lower down. 3.27? what about a 3.00?

With a Super Charger I have to wonder if a 3.00 might not be a good idea with expensive gas.

is it 3.27 and 3.00? if not what is the ratio?

sd8683
05-11-2008, 04:40 PM
Everyone talks about going to a 4.10 rear end but what i want to know is what is lower down. 3.27? what about a 3.00?

With a Super Charger I have to wonder if a 3.00 might not be a good idea with expensive gas.

is it 3.27 and 3.00? if not what is the ratio?

3:23's maybe???

Blk Mamba
05-11-2008, 04:52 PM
I personally would rather have a two speed rear end, say 3.23's, & 4.56's. Horsepower is speed, and torque is quickness.

jgc61sr2002
05-11-2008, 05:56 PM
The higher the # the lower the rear end ratio.:D

KillJoy
05-11-2008, 06:49 PM
If you would prefer freeway speeds at a lower rpm, at the loss of low speed acceleration, get a lower numbered gear.

I chose 4.10's ;)

KillJoy

Aren Jay
05-11-2008, 08:47 PM
Do "they" make two speed rear ends?

and who are "they"?

I want to improve my gas mileage, if need be, and make up for any short falls with a SC.

I would want to be fast enough not to be embaressed by a Camry, WRX, or STR-8 300C or Challenger.

1 would rather get 20 MPG than 5.

Stranger in the Black Sedan
05-12-2008, 04:58 AM
Lower gears are likely not going to improve gas mileage. Gear ratio is only a very small part of the equation.

If you take an engine like the DOHC engine, which has a midrange power band, and lug it at super low rpms on the highway, you are probably going to get the same or worse gas mileage than if you run the engine closer to its torque peak, at cruise.

Notice that the 4.10 guys claim the same mpg as the 3.55 guys.

Waste of time.

hot-rauder
05-12-2008, 05:43 AM
Lower gears are likely not going to improve gas mileage. Gear ratio is only a very small part of the equation.

If you take an engine like the DOHC engine, which has a midrange power band, and lug it at super low rpms on the highway, you are probably going to get the same or worse gas mileage than if you run the engine closer to its torque peak, at cruise.

Notice that the 4.10 guys claim the same mpg as the 3.55 guys.

Waste of time.


so what is the point of 3.73s? the difference would be so minimal...

sd8683
05-12-2008, 06:00 AM
Do "they" make two speed rear ends?

and who are "they"?

I want to improve my gas mileage, if need be, and make up for any short falls with a SC.

I would want to be fast enough not to be embaressed by a Camry, WRX, or STR-8 300C or Challenger.

1 would rather get 20 MPG than 5.

When I put my 4:10's in there was pretty much no differance in MPG's, I still get between 240-260 miles per tank.

Stranger in the Black Sedan
05-12-2008, 06:17 AM
I did not install 3.73s for gas mileage or accelration improvement. I have been through several gearsets in this car troubleshooting axle noise. I got a free set of new Ford racing 3.73s in the process so I figured what the hell

ckadiddle
05-12-2008, 06:46 AM
The words "super charger" and "expensive gas" should never appear in the same sentence together. ;)

Go Mifuni
05-12-2008, 12:29 PM
Give me your supercharger. That should help you get better gas mileage. :D

Blk Mamba
05-12-2008, 05:15 PM
Do "they" make two speed rear ends?

and who are "they"?

I want to improve my gas mileage, if need be, and make up for any short falls with a SC.

I would want to be fast enough not to be embaressed by a Camry, WRX, or STR-8 300C or Challenger.

1 would rather get 20 MPG than 5.

A friend of mine in the early 70's had a Merc Talladega (the race car) he manufactured a two speed rear end for it, so the answer is "no" but also at that time auto's were not so sophisticated, and you could use a two speed rear end, and not have to worry about power bands and torque curves.

RF Overlord
05-12-2008, 05:39 PM
The most common gear ratios available for the Ford 8.8" rear end are

2.73
3.08
3.27
3.55
3.73
3.90
4.10
4.30
and 4.56

I think they make a 5.12 as well, but that would be ludicrous on a daily driver...

Diabolical, with the 18" rims and tall rear tire on the MM, you would lose a LOT of acceleration if you went lower than 3.27, and you gas mileage would likely not improve as you would have to push the motor harder to get any kind of pickup at all, unless the car were exclusively highway-driven. Adding a supercharger to the mix would be worse with a lower numerical gear ratio as you would break things more easily.

Also note that the 3.08 ratio is NOT recommended for the Panther chassis...it makes some very peculiar resonances.

Aren Jay
05-13-2008, 09:49 AM
So who is going to cvt their Marauder?

QWK SVT
05-13-2008, 10:46 AM
So who is going to cvt their Marauder?

No one. The cost to do so would negate any gains from it... IMO, CVTs haven't evolved enough yet for me to purchase a vehicle that was built with one - let alone contimplate retrofitting one in an existing vehicle...

Stranger in the Black Sedan
05-13-2008, 11:01 AM
A 5 speed auto would be a worthwhile mod though.

vkirkend
05-13-2008, 11:17 AM
The words "super charger" and "expensive gas" should never appear in the same sentence together. ;)

:lol::bows::banghead::laugh: