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3.55 worth it?

BmacIL

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I believe that for the 5.0 models, this governor/limiter is now set at 155mph. Also, the EB is 149 and the V6 is 121. This is to the best of my knowledge, however I could be mistaken :D
I believe the 155 is for GT Perf Pack, EB is 145 for the Perf Pack, and V6 is 121. The GT and EB non-perf pack models are lower (lesser radiator packages, brakes and tires), but I don't know what the number is.

He had originally posted this in the V6 forum, so that's where the 121 answer came from :thumbsup:.
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Jamo

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Big time. Don't leave home without it.
 

stang9779

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Just go 3.73 or stay home.
 

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15GTBEN

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I believe the 155 is for GT Perf Pack, EB is 145 for the Perf Pack, and V6 is 121. The GT and EB non-perf pack models are lower (lesser radiator packages, brakes and tires), but I don't know what the number is. .
Where did you hear that BS about the GT non PP top speed being lower?
The changes to the 15'GT's top speed over the 11-14 GT's are due to the engine improvements, not just exclusive to the ''all mighty'' PP.

Ive hit 150 in my stock 11 GT base non track pack with the 18 inch all season and 2 piston calipers). The 15' GT isn't going to be slower than that...
 

jaymayne

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Where did you hear that BS about the GT non PP top speed being lower?
The changes to the 15'GT's top speed over the 11-14 GT's are due to the engine improvements, not just exclusive to the ''all mighty'' PP.

Ive hit 150 in my stock 11 GT base non track pack with the 18 inch all season and 2 piston calipers). The 15' GT isn't going to be slower than that...
I have a 2015 Premium GT non pp, and unless my speedo is off I've been 160 in 5th. From what I understand they limit them at 164.

Edit: I have 3.31 and the stock 20's
 

Strokerswild

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In any case, Ford Racing will be selling all the ratios for $180. You're not stuck with what you buy.
Not necessarily the case if you have 3.15s - the FRPP book says the numerically higher gearsets aren't compatible with the 3.15 rear. Beware!

On topic, don't fear the gear! :thumbsup:
 

Old 5 Oh

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It's just math. Revs with the 3.15 are always 89% of the revs a 3.55 car would be turning at the same speed. So when the 3.55 car is turning 2,000 RPM, the 3.15 car is turning 1,775. Not a lot of difference.

And this shows in performance. Check the 1/4-mile threads. There's about a 0.1 or 0.2-second difference between the two (and both are faster than the PP 6MT.)

As to mileage, it looks like maybe 1 or 2 mpg on the freeway. My car will get 28-29 at 70 now that it's broken in, and that's a little better than what I have seen on the 3.55 cars. Again, not a lot.

I chose the 3.15s (I ordered the car and could certainly have checked the box for 3.55s) to make the car a relaxed cruiser. It's still got plenty of gumption (see the 1/4-mile results; a 12.8 will do for me) and it's just what I wanted.

It all depends on the kind of car you are trying to create. "Better" and "Best" are rough words to use when talking about the various rear gear, transmission and suspension options. We all have different tastes and needs.
 

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Spartan

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It's just math. Revs with the 3.15 are always 89% of the revs a 3.55 car would be turning at the same speed. So when the 3.55 car is turning 2,000 RPM, the 3.15 car is turning 1,775. Not a lot of difference.

And this shows in performance. Check the 1/4-mile threads. There's about a 0.1 or 0.2-second difference between the two (and both are faster than the PP 6MT.)

As to mileage, it looks like maybe 1 or 2 mpg on the freeway. My car will get 28-29 at 70 now that it's broken in, and that's a little better than what I have seen on the 3.55 cars. Again, not a lot.

I chose the 3.15s (I ordered the car and could certainly have checked the box for 3.55s) to make the car a relaxed cruiser. It's still got plenty of gumption (see the 1/4-mile results; a 12.8 will do for me) and it's just what I wanted.

It all depends on the kind of car you are trying to create. "Better" and "Best" are rough words to use when talking about the various rear gear, transmission and suspension options. We all have different tastes and needs.
Old did you ever test drive the GT with 3.55 gears? A lot of the auto buyers on here say once you feel the auto with the 3.55s the difference is night and day. Basically the 3.55 or 3.15s and the Reverse sensing pack are the last 2 options I'm trying to figure out before ordering this weekend.
 

neodark

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Premium autos (non-pp) seem to get 3.31s, check the sticker on your differential. Base autos seem to get 3.15s
 

EcoSwag1990

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Old did you ever test drive the GT with 3.55 gears? A lot of the auto buyers on here say once you feel the auto with the 3.55s the difference is night and day. Basically the 3.55 or 3.15s and the Reverse sensing pack are the last 2 options I'm trying to figure out before ordering this weekend.
If your're getting a premium don't waste your money on the reverse sensing. I've see several ppl with it say it was more annoying than helpful. The camera view is amazing though
 

DavisCustoms

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Everyone has a personal preference to which gear set to chose.

If you plan on leaving the car stock, definitely go with the 3.55's. it will feel snappier.
If you plan on modifying the car, 3.15's or 3.55's will work.

In regards to mileage... I still manage to get 18mpg from my daily driven 94 F150 with a 5.0 HO,Automatic, 3.55LS with 260,000 miles on it... so don't let people tell you that you'll lose more than 2-3mpg depending on how you drive.

I'll have a used 3.55 ratio factory set available soon (26,000 miles on them)
changing to 4.88 ratio :D
 
 








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