3.73s are in!

[Husky44]

Just finished my 3.73 install. This is how they cars should have come from the factory. Car is much smoother to drive around town, pulling away from stoplights, etc... And then you get in it, and WOW!

I can't recommend this mod enough. It's the first mod to my car, and should be to every 13-14 GT500.

Do it.

 

[Norton]

Congrats!

 

[my13Elenor]

Where do you have to shift now? Mph to gear? How much will it effect the top end? Do you have drag radials? Doesn't it spin more now? :banana:

 

[Snoopy49]

Where do you have to shift now? Mph to gear? How much will it effect the top end? Do you have drag radials? Doesn't it spin more now? :banana:

 

[HAMMRHEAD]

I want to do it, but traction is hard enough to find in 1st now - even with my MT's!
My car has Van's 13-6 kit as well.

 

[Husky44]

Snoopy-THANKS! Call me crazy, but I don't typically know where I shift, I do it by ear, not by tach.

No drag radials, still running factory GYs.

No significant difference in traction--I live in AK, and it's barely in the 40s. I don't bury the pedal, ever. I roll into the throttle, and stay right at the edge of traction (spend six months of the year driving on snow and ice, and you learn to feel it). I feel like I have better response, and more control than I did with the stock gears. Biggest difference to me is I'm able to get out of the clutch a lot quicker, smoother, and with less throttle on regular starts from a dead stop. Used to have to feather it a lot more to ease out (vs. launching into the car in front of me at the light).

 

[Lethalchem]

I'd like to do this mod at some point. I have a feeling I'd be much happier with the car. The 3.31's don't let it feel like the beast I think it should be. A larger blower on a 5.8 should feel more torquey than a small one on the 4.6 of my old '03 Cobra, but the gears soften it up too much for my taste. I know it would give me the feel I'm missing, I'm just not ready to put a tune on the car yet. Sounds like you love it, congrats! :beer:

 

[BAS]

I would agree... Would love to do this mod. I changed up from 3.64 to a 3.91 on my M3, with a lightweight flywheel it revved up so fast and was so lively.

The 3.31s on the Shelby make it feel as though the high RPMs are an upcoming event next week rather than the race car immediacy it should have.

Although I drove the car like I stole it yesterday, for the first time - it is absolutely savage when it gets going.

 

[Husky44]

I'm just not ready to put a tune on the car yet. Sounds like you love it, congrats! :beer:

Lethal: no tune required. Ford dealer can reset the gear ratio for you. I'm not an expert in this, but have talked to several folks, including the service guy at the dealership, and it's a preset selection to change gear ratio from 3.31-3.73 (or several other common ratios). Hope to get mine in Friday.

If that's the only reservation you have, then go for it. You're exactly right about the feel that's missing.

 

[72MachOne99GT]

Anyone ran the quarter with 3.31s vs 3.73/4.10s?

Wondering if that shift to fourth is doing much to the times.

 

[Lethalchem]

Lethal: no tune required. Ford dealer can reset the gear ratio for you. I'm not an expert in this, but have talked to several folks, including the service guy at the dealership, and it's a preset selection to change gear ratio from 3.31-3.73 (or several other common ratios). Hope to get mine in Friday.

If that's the only reservation you have, then go for it. You're exactly right about the feel that's missing.

I was hearing people initially saying their dealerships where giving them some problems, saying they couldn't do it. Perhaps that's changed now and it's time for me to go to a local dealership and find out. :beer:

 

[Husky44]

Anyone ran the quarter with 3.31s vs 3.73/4.10s?

Wondering if that shift to fourth is doing much to the times.

@Birddoc has, I think wih Bot 3.73s and 4.10s...

From what he's said, the 4.10s are the better choice with a car that's going to see a lot of 1/4 mile use, but 3.73s were his recommendation for all around performance.

 

[Lethalchem]

I have yet to see track results from JUST a gear change though. That's what I'm most curious about.

 

[sb03cobra]

Lethal: no tune required. Ford dealer can reset the gear ratio for you. I'm not an expert in this, but have talked to several folks, including the service guy at the dealership, and it's a preset selection to change gear ratio from 3.31-3.73 (or several other common ratios). Hope to get mine in Friday.

If that's the only reservation you have, then go for it. You're exactly right about the feel that's missing.

I hope you are correct. 3.73's are the only mod that I want, but I will not void my warranty to do it.

 

[Norton]

I hope you are correct. 3.73's are the only mod that I want, but I will not void my warranty to do it.

x2. 3.73s are one of the few mods in which I'm interested, but I don't want to do anything (like a tune) that will void my warranty.

 

[Blackdevil77]

I have yet to see track results from JUST a gear change though. That's what I'm most curious about.

Me also. I'd like to see what difference just the 3.73 gears make in 1/4 times.

 

[Florian]

what was the price on the swap?

F

 

[carguy19]

I feel as if the stock gear is not even close to tall enough for the car. At 65-70 mph the car is taching out at about 1200-1500 rpm and seems to be lugging if you try to pass without downshifting.

I think that ford did the 3.31 gears to hit the 200mph mark and to make the car not fall under the gas guzzler tax threshold. I think that any of the 3.73 3.90 or 4.10 wouldnt be too tall for the car at all.

I'm gonna do the 3.90's I think.

 

[Husky44]

what was the price on the swap?

F

Parts were ~$220 from Tousley Ford, for the gears and a small parts kit (was able to reuse the pinion bearing), plus shipping ($50 to AK, but still a better deal than I could find anywhere else).

Labor was free. My buddy has been doing drivelines for decades, and did it for me. Made me feel like a putz. I did my own swap on my 95, and took about 10 hours just to get the pattern "good enough", and they still make some noise. He took longer to get the old carrier and pinion out than he did to set up the new gears, and they're dead on. I swear he didn't even crawl under the car, but kinda stood back and underhanded the carrier in like a softball pitch--and the pattern was perfect. It's fun watching an expert at work. No noise, smooth as can be. :beer:

 

[dotmpeg]

What else is needed besides the gears to swap them out? Gaskets? Bearings? I've never done it before and want to do it right.