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Ready to order - 3.55 or 3.15 diff?

Tristar

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3.15 Thumbs Up

I got the GT Base with 3.15 and its fine for me and I like the MPG too. I will never use all the power this puppy has, love the way it feels and drives so far with 3.15.

Chris
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BmacIL

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Right. Here is an example for the 3.15 gear. Let's say I am going 71mph in 6th @2000rpm.

Looking at the gear chart, if I want to pass someone, I just click twice on the left paddle to go from 1900 to 3100 rpm (=71mph), then goose it to 4000rpm and I am going 90mph! Lift off the throttle and the auto shifts back up ... aaand we're back to cruising speed. Done. No muss, no fuss.

Around town? About 3-4mph difference between the two ratios for the same rpm. Who cares about performance when I am stuck behind the guy in front of me anyway?

Question - does the Coyote mind tooling around town at only 1750rpm on occasion?
Seems to behave just fine at that speed.
 

Remy_reign

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Can't just do a straight 3.15 to 3.55 gear swap without also replacing the diff.$$
Yeah, Ford quoted me at 900 to 1100, i paid 800 in my 13 so i figured its not a problem. I hear a lot of ppl are getting them done cheaper as well. Just wish i had a chance to order mine instead of picking it up from a dealers lot.
 

Cascadia_302

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Yeah, Ford quoted me at 900 to 1100, i paid 800 in my 13 so i figured its not a problem. I hear a lot of ppl are getting them done cheaper as well. Just wish i had a chance to order mine instead of picking it up from a dealers lot.
Actually CJ Pony parts has the 34 spline trac-lock diff for $190 and 3.55 gears for $200.
You still need the shim set to go with the install.
If you search I would think other vendors would beat those prices.;)
 

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GTP

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Back in my college days I raced bicycles in the Colorado mountains. Bikes were 12 speeds in those days. We would change the rear wheel gear cluster depending on whether the race was flat, mountains, or rolling terrain. We calculated every gear combo (racers don't use triple front cranks), and knew how to shift both front and back to find each one. Some of us (me) hand-picked each cog to ensure more uniform spacing of the ratios. Nowadays, bikes come with 10 cogs in the back, instead of 6. So that's 20 speeds, not just 6. No more need to calculate or hand-build gear clusters anymore.

Short of customizing each gear, it will be nice if an 8-speed auto trans came out. ;)
 

bluebeastsrt

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Can't just do a straight 3.15 to 3.55 gear swap without also replacing the diff.$$
And this is why you just order the 3.55s from the factory.:D Don't be disappointed with sluggish stop light performance.
 

Poppacapp

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And this is why you just order the 3.55s from the factory.:D Don't be disappointed with sluggish stop light performance.
My 3.15 equipped Gt is not sluggish at all. I believe the track times these cars are turning in states that too. :thumbsup:
 

GoBlues38

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back in 1989, my LX 5.0 had 2.73 rear end gears. yeah, it cruised all day long on the highway, but the other gear was 3.08 back then, and i constantly got my ass kicked by those cars. It just wasn't fun to drive.

a lot of guys were going from the 3.08 to 3.55.

moral of the story. always split the difference of the 2 extremes and have the best of both worlds.

i have the 3.55's and love them
 

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Alloye

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Having had both, I recommend the 3.55 setup.
 

El_Centenario

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Mine is 3.15, and in no way feels slow... guess what.. the tranny downshifts!! :) Also, 3.15s are running as quick as 3.55s in the 1/4.

Also, 3.15 will be the PERFECT gear for my turbo setup. :headbang: :headbang:
Exactly what I think! No need to regear if going with boost, less traction issues.:clap2:
 

Rich of So Cal

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I'm sure you can tell a difference if you drive it long enough, but I did a test drive with the 3.55, then the car I bought came with the 3.15. With an automatic I couldn't notice much difference. But then, my time with 3.55 was limited. If it hadn't been black, I might have bought the test car....but I am getting out of an 8 year relationship with a black car, so no thanks. Maybe I'll upgrade later, but having lots of fun with what I've got, even at stop lights!
 

fundando

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3.55 all the way. I have driven both and it is worth it if you actually will go fast or if you ever plan to go to the drag strip. If you are gonna drive it like a grandma it wont make a difference.
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