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Discussion Starter #1 (Edited)
Seeming as this may be my next mod, I was hoping to get some specific input.

I am currently getting 502 rwhp (adjusted) with SCT tune and JLT intake.

Is 3.73 too much gear???

Any input would be appreciated, thanks.
 

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I seems most guys go with 3.73....not sure why....but reading around here will show you this!

:shrug03:

OSHELBYO
 

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I seems most guys go with 3.73....not sure why....but reading around here will show you this!
For 20" wheels or for those running taller than stock drag radials the 3.73 are a great street/strip compomise.

The 3.55's are a good street option but for the cost involved, most feel it is too little gain for the expense.

For stock sized wheel/tire combo (27" diameter) 3.73 still return ~2K rpm highway cruising at 70 mph.
 

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love the 3.73 gearing =D
 

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I absolutely love the 3.73s - smoother starts, much quicker response at the wheels, perfect for my kind of driving - and BTW, definitely get the KR mufflers! You'll love cruising around at 3,500 rpm!

frisco
 

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Depends how far you go with the engine and what tires you run. It seems most go with the 3.73 but if you are going to boost the engine on up you may find 1st becoming worthless.:zlurking:
 

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Discussion Starter #7
Thanks for the imput guys. Pretty much the way I was leaning was towards 3.73's.
 

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Had 3.73's done this weeked-first mod after a years ownership-Axlebacks don't count. Dealer plugged in his laptop and selected KR-3.73 gears. Driving home the speedo seems really optomistic. No gps, but judging by cars on the road looks to be 10% off. Indicated 80 and most of these left lane morons wont go over 70 so I must be doin 71+_. Next, a month or 2, when discresionary cash allows, cai and tune. Those that have done the 3.73 gears and corrected speedo on the hand tuner is your speed/odo pretty accurate now?
 

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No issues with speedo after doing 3.73 gears. I used the SCT programmer.
 

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My 331 gears flame the tires in 1st and 2nd now, I don't think I want them flaming in 3rd. my bad, (I meant the 331 gear set in this original post, sorry)
 

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Same here, after my dealer installed the 3.73 they used their laptop and said the speed should be set. It was not, until I reprogrammed with my SCT from Justin. Example: Using stock tires 27" dia. At 70mph, 3.31 gear = 1817 rpm, while 3.73 gear = 2046 rpm.
 

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My 355 gears flame the tires in 1st and 2nd now, I don't think I want them flaming in 3rd.
Joe, was there a noticable improvment in performance and drivability with the 3.55 gears? I often read that there's not enough of a difference between the stock 3.31s to justify them, but those remarks are mostly subjective from those that have changed to 3.73s. Right now, I'm thinking 3.73s as well, but I'd like to hear an opinion from someone who has switched to the 3.55 gears.
 

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Joe, was there a noticable improvment in performance and drivability with the 3.55 gears? I often read that there's not enough of a difference between the stock 3.31s to justify them, but those remarks are mostly subjective from those that have changed to 3.73s. Right now, I'm thinking 3.73s as well, but I'd like to hear an opinion from someone who has switched to the 3.55 gears.
+1. Before deciding on the GT500 I drove quite a few Mustangs including GT's with both standard (don't know the ratio) and optional 3.55 gears. I definitely noticed a difference and intended to add the option. Fortunately I found a deal on the GT500 I could live with but no option to go with 3.55. I have delayed upgrading gears because all the available opinions were that 3.73 was the way the go, but I'm a little afraid that I'm too much of a wuss for that tall of a gear.
 

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Joe, was there a noticable improvment in performance and drivability with the 3.55 gears? I often read that there's not enough of a difference between the stock 3.31s to justify them, but those remarks are mostly subjective from those that have changed to 3.73s. Right now, I'm thinking 3.73s as well, but I'd like to hear an opinion from someone who has switched to the 3.55 gears.
Ivan, I screwed up, I have the stock gears I dont know why I had 355 on the brain, but it still would be hard for me to justify the 373s for the same reason as I stated before.
If I keep the tires from roasting second, that is where I notice the hardest pull thru the gears. If I went to 373 I can only imagine the tracktion loss in second
 

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must be the damn meds:mofo:
 

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Here is my experience thus far (~24 hours with 3.73's)

1) Much smoother pulling away from a complete stop.

2) It also decreases the overall gearing gap between 1-4 gear.
When quick shifting the car is much easier to maintain at peak torque due to the closer overall ratio

3) Less tire spin! It's true, I get less wheel spin with the 3.73s!

4) About 200rpm increase in 6th gear on the highway. I can live with that.
6th gear can actually be used now, that is a pleasant change.
 

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Everything makes sense except for the less tire spin part. Can anyone explain how this works? You're putting more torque to the wheels.
 

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Here is my experience thus far (~24 hours with 3.73's)

4) About 200rpm increase in 6th gear on the highway. I can live with that.
6th gear can actually be used now, that is a pleasant change.
+1

Totally Agree!

this car should've come from Ford with 3.73 IMHO.

I think the 3.31 was picked to tweak the 0-60 time for the mags with crappy drivers and prevent inexperienced drivers from killing themselves. Why should a 2nd gear hit 70+ mph at red-line when there are 6 gears, that's crazy.

I think you'd probably be happy with a 3.73 gear as most here are.

TD
 
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