Has this been done? 273's

[black 10th vert]

thats a bad idea with a 3800lb+ car. if anything, i'd go 3.90s and probably improve your city mileage with the fact you could lug around in 4th and 5th gear alot without fear of bogging the car down. these t56 1-4 ratios are already steep versus the old t45/3650 tranny

I agree with this statement totally. If you want to try it, though, it might be worthwhile (for you), as it will be only a few hundred to prove (or disprove) your theory. Personally, I feel this heavy ass car needs all the gear/torque it can to get off the line, as I'm coming from a 2,200lb. '65 Cobra replica with 350hp, and 3.55's in the rear. These cars are pretty quick, but nothing compares to shaving almost 2000lbs. off with similar power!:burnout:

 

[IronTerp]

You know, on second thought, if you're really in to getting better gas mileage, have you considered swapping some Viper or Vette 5/6th gears into the T-56?Our 6th gear final is like .65 or so correct? I think the Vette's are like .52. This way, you'd still have great performance in 1 through 4th, and be able to RPM way down on the highway.

 

[TRBO VNM]

I had 3.31's in mine and finished the 1/4 in 3rd gear. i was preparing for my turbo setup, so I put those in when I did the solid swap, but ironterp convinced me to keep the eaton on for a bit longer so now I have 3.73's in.

no clue on the gas mileage really. I did take it to Ga for xmas time and got over 300 miles to the tank. I beat that though with my first comp o. it had the 3.55's and turbo and I got over 350miles to the tank on a trip to florida.

 

[boosted2000si]

Why change the gear?

You should just pull the motor and swap a v6 in there, youll get all the gas milage you want.



This thread really ranks up!

 

[cobra101]

Excellent info, all good poiints. I run around town at 1200 rpm (I just won't make 15lbs boost at 1300 rpms is all) so .390s won't get me better mileage. Anyways, lots of info. That's one bad arse ride sniperdog, I love it. Bet it pulls like a mofo. Glad someone thought like me And yeah at speed limit on the hwy you probably would get 24+ 308's and especially 273's guaranteed 25MPG+. Still romp on 99.9% of the cars on the street I bet too. Probably never use 5th and 6th gear around town (maybe not even 4th much).

 

[cobra101]

Thats just an &^%^%^ response...

Why change the gear?

" You should just pull the motor and swap a v6 in there, youll get all the gas milage you want. "


Ahhhhh Yeah but then you won't jhave 700HP and beat 99.9% of all cars on the street, jeeze. Some people just want to be some people.

 

[cobra101]

You know, on second thought, if you're really in to getting better gas mileage, have you considered swapping some Viper or Vette 5/6th gears into the T-56?Our 6th gear final is like .65 or so correct? I think the Vette's are like .52. This way, you'd still have great performance in 1 through 4th, and be able to RPM way down on the highway.

This was done by a couple of members, With success. Much more expensive Job I believe rather than the 300 gear mod (and easily reversible too).

 

[cobra101]

I agree with this statement totally. If you want to try it, though, it might be worthwhile (for you), as it will be only a few hundred to prove (or disprove) your theory. Personally, I feel this heavy ass car needs all the gear/torque it can to get off the line, as I'm coming from a 2,200lb. '65 Cobra replica with 350hp, and 3.55's in the rear. These cars are pretty quick, but nothing compares to shaving almost 2000lbs. off with similar power!:burnout:

Yeah but that isn't similar power, 350hp vs 700hp. And don't get me wrong this thread was started to see if anyone had done it. I am NOT saying I am runnning out and doing it.

It appears that sniperdog may be one of only a few to do it. I believe him when he says it is awesome and I believe it was hooking better.

Fun FUN

 

[IronTerp]

This was done by a couple of members, With success. Much more expensive Job I believe rather than the 300 gear mod (and easily reversible too).

True, Several MACA folks have done it and the parts alone run about $500 I believe. But, they all love it. :banana:

 

[crystal_SVT]

Why change the gear?

" You should just pull the motor and swap a v6 in there, youll get all the gas milage you want. "


Ahhhhh Yeah but then you won't jhave 700HP and beat 99.9% of all cars on the street, jeeze. Some people just want to be some people.

i think its rather silly to make your car that much slower to gain an extra few mpg.. last time i checked gas is still pretty cheap anyways. a 3800lb car with 2.73 gears equals a turd even with 700 hp... but if gas milage is your only concern then by all means... :thumbsup:

 

[68_GT]

a 3800lb car with 2.73 gears equals a turd even with 700 hp

I doubt that hell it may even be faster if it imrpooves traction :bored:

 

[SCT2003]

2.73's were stock in the old five speed 5.0 cars. 3.08's were in the AOD's and in cop cars as well.

I've had five pre-94 5.0's and if I'm not mistaken...2.73's were the norm from the factory but you could special order the stick with 3.08's and the auto with 3.27's. 3.55's and above were all aftermarket.

I've run everything from 2.73's-3.73's and don't know why anyone would want 2.73's or numerically lower unless they had a great deal of HP and also ran events like the Silver State.

I had an old Camaro with 2.56's and dropped a whole second with 3.73's gears.

I think 3.55's are best all around in the 03-04's but I sometimes think about upping the ante to 3.73's or 3.90's just to see how she reacts???

:beer:

Later...Dave

 

[XJRGUY]

<SNIP>
The fact is, does anyone know of ANY car EVER that got 24 MPG+ with 700BHP? Anyone who knows anyone who knows anyone who knows ANYONE who ever got that type of efficiency? Closest thing I can think might come close is a twin turbo supra of old. <SNIP>

2008+ Viper with minor bolt ons get 670+ at the motor and 22+ MPG :shrug:

Yeah I know not 700HP or 24+ mpg but still pretty impressive with a smog legal 8.4L V10.

 

[XJRGUY]

2.73's were stock in the old five speed 5.0 cars. 3.08's were in the AOD's and in cop cars as well.

Yeah my first 5.0L was a 1989 Cabernet Red/Titanium 5 spd with 2.73's.

I was SOOO happy to dump that sh*t and put in 3.55's

Felt like I picked up 100HP. :banana:

 

[Qwk GT]

I know the car is supercharged, but my 87 gt had 2.73.... Damn, it was really sluggish, after the 4.10's, really woke the car up. So I would think a drop from 3.55's to 2.73's would be a big drop.