Opinions on Rear Gear Ratio

[BabyDiesel]

Originally Posted by Baltothewolf

Guys my '91 5.0 has 2.73 and it cruises at 50 in 4th just fine? I don't drive it carefully so I can't vouch for MPG's, but yea. Was just tossing that out there.

Not slamming you Balto, but I'd imagine that the 5.0 has a good bit more bottom-end torque than the 4.6. Hence the better drive-ability with 2.73's

The 4.6 in a 99 2wd SCLB Ford F-150 I used to drive was... ahem, pathetic. I hope it fares better in the Vic!

3.08zzz

[Baltothewolf]

Originally Posted by BabyDiesel

Not slamming you Balto, but I'd imagine that the 5.0 has a good bit more bottom-end torque than the 4.6. Hence the better drive-ability with 2.73's

The 4.6 in a 99 2wd SCLB Ford F-150 I used to drive was... ahem, pathetic. I hope it fares better in the Vic!

3.08zzz

Well then, I learned something! I didn't think about the torque haha.

[24601]

For comparison's sake, the pushrod 5.0L in the 94 GT made 285 ft-lbs at 3500 rpm compared to my 4.6L's 285 ft-lbs at 3000 rpm.

Also, I'm not disagreeing that 3.08s may be the better choice, but I do want to point out that 2.73s were standard in the civilian model Crown Vics. Just wanted to provide more insight to the discussion.

[mcrews]

I would lean toward the 308 gears.
Your print out looks on the 308 looks likes the rpms on the Q45.
I was pretty happy w/ them.

[Daox]

Your power will suffer, but I highly doubt you'll be lugging the engine. Everything I've ever seen says taller gearing = better mpg (until you lug). I'd definitely go 2.73, especially if the civilian model came with it. You know its okay then.

[svt98t]

I have 2.73s in my 93 Grand Marquis and I love them.
They are the shizzle on the highway.
I have 3.08s in my Town Car, and they are ok for what it is.
There is a 500# difference between the two cars as well.
I'd go 2.73s. Get them from RockAuto for cheap.
Then sell your 3.55s. People out there will buy them.
And thats how you make your money back.


-ryan s.

[cRiPpLe_rOoStEr]

I'd only go with the 2.73 after some weight reduction. Or with some forced induction...

[ksa8907]

3.08 plus taller tires? Higher load ratings and pressures will decrease your rolling resistance. And filling in the wheel gap better will increase aerodynamics a bit(probably very small bit).

[Big Dave]

There are still plenty of old 94-96 D-Body Fleetwoods running around with 2.56 gears and 350 LT1 engines.

Lower engine RPM at a given road speed = better MPG. The trade-off is sluggish acceleration.

I thought this site was all about the MPG.

[svt98t]

FYI, with 2.73s in my 93, I ran a 17.52 @ 81mph in the 1/4 mile.
Acceleration does suffer a bit, but you don't go to WOT while hypermiling.

I'd still go 2.73s.


-ryan s.