GT350 gears and speeds

[scottpe]

As someone who tracks his car and also likes to have fun on the street (responsibly, of course ;) ), I think you're understating the value of a 0-60 time... Sure, it's not very meaningful if ALL you're going to do with the car is drive closed circuit tracks, but that's not the only thing that's fun to do even with a track-built car. People who drag race their car will be interested in acceleration from a dig, too, and the track crowds and drag crowds aren't mutually exclusive. Plus, a 0-60 time is indicative of stoplight and on-ramp fun potential.

I think it's kinda closed minded to dismiss 0-60 as only useful for magazine racers.

I never underestimate the value of acceleration. I'm a drag racer at heart. However, let's be realistic here, the difference in 0-60 time, for any reasonable first gear ratio Ford chooses, is probably going to be no more than a couple tenths. Most people are not going to notice that on the butt dyno. But when the numbers are posted in black and white in the car rags, everyone notices.

I didn't mean to imply that it's only a useful stat for magazine racers. That's just where that particular figure seems to get a lot of the attention. It's not like drag racers sit around talking about what kind of 0-60 times they pulled at the track. ;)

Trust me, I want this thing to be as fast as possible in every category!

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[Katastrophe]

I was wondering when this conversation would come up...

This is a great website for figuring RPM/speeds out. I've already plugged in what most have speculated: 3.73's out back with gear set C in the Tremec.

http://www.car-videos.net/tools/spe...o7=&Redline=8250&Increment=250&B1=Recalculate

Tremec does say they can do custom gear seats...but who knows.

Either way, it doesn't look like too bad of a setup as is.

 

[Skullbussa]

I care much more about 75mph cruising RPMs and gas mileage than I do about pissing contests over 0-60 times which are metrics that RWD cars like Mustangs and Corvettes are never going to be great at.

Now, 60-120mph....I do care about that.

 

[Hack]

I don't care about fuel economy. If I did I would buy a Fiesta.

I'd like to see the car geared so you are out of first by 30-40 mph at the fastest. Why make first so tall that you're in it through the entire 0-60? Cruising RPMs don't affect fuel economy much anyway. 60 mph should arrive at the top of 2nd gear.

 

[Jimdohc]

When I consider 1st gear I think about how much I have to slip the clutch when starting off, especially around town. Super tall gears would require a lot of clutch slipping. The '13-14 GT500 enjoyed an enormous torque advantage over what we are assuming will come with the Voodoo. That will likely play an important role in Ford determining which gears to choose.

2.87 first (2.87 is also 1st gear in TKO600) with 3.73 would be ~40mph on '90 5.0 or ~50mph on '15 GT.

GT350 has more torque than both. ~62mph is only due to high redline.

I don't think first will be good for much more than 50 MPH, and maybe not even that much. This engine isn't going to be a torque monster, and while it will have significant HP, it is unclear to me what the low end is going to be like. Also, Ford has been pretty clear in saying that this car is intended for both the street and track.

So, while a tall first gear might be great on the track (where you never use it), and while it might be great for an engine making lots of torque, I'm not sure how great it will be for this engine.

I suspect that the ratios will be close to the "options C" ratios posted earlier. Although, those did go to 55 in first, at which point you'd almost think going to 62 would be pretty similar.

-T

Lexus LFA does ~66mph in 1st, only has 354tq (553hp) and C&D curb weight of 3,583lbs.

of course, I have no clue what it will really have. Just making conversation.

 

[ilkhan]

Remember the voodoo doesn't make too much additional torque, it just spins a lot faster. Id assume a pretty flat curve peaking at around 420-440 ft-lb at around 5k rpm. Not having to shift out of first makes a decently sized difference in the 0-60 time. With 8200rpm available getting to 60 in first would be a good plan for them and shifting to second would only take you right back down to the torque peak. And its still a V8, so street manners would be fine.
Use 1 for 0-60
Use 2-4 for general track / 2-5 for a really fast track
Use 5 for top speed
Use 6 for cruising fuel econ
Unless they say otherwise, the 3.73 is perfectly appropriate to use as a rear gear.

We already know tires are upgraded pilot super sports (I assume they are PSS2 and pilot just hasn't made a general announcement yet), so they have plenty of grip.

 

[Hack]

Another reason to argue for steeper gears is you can't downshift into first on a track, but you want to be in the power band even in tight corners. So preferred is that you are in the power band in 2nd gear on those corners.

 

[Grimace427]

Official ratios posted: http://www.mustang6g.com/forums/showthread.php?t=20366

1st: 3.253:1.............55.48mph
2nd: 2:233:1............77.38mph
3rd: 1.611:1.............111.98mph
4th: 1.24:3..............145.4mph
5th 1:1....................180.29mph
6th: .629:1..............(xx rpm @60, will edit later)
Reverse: 2.955:1.

 

[arsenalrocks]

What is the rpm @62mph 6th gear?

Official ratios posted: http://www.mustang6g.com/forums/showthread.php?t=20366

1st: 3.253:1.............55.48mph
2nd: 2:233:1............77.38mph
3rd: 1.611:1.............111.98mph
4th: 1.24:3..............145.4mph
5th 1:1....................180.29mph
6th: .629:1..............(xx rpm @60, will edit later)
Reverse: 2.955:1.

 

[Sered]

Official ratios posted: http://www.mustang6g.com/forums/showthread.php?t=20366

1st: 3.253:1.............55.48mph
2nd: 2:233:1............77.38mph
3rd: 1.611:1.............111.98mph
4th: 1.24:3..............145.4mph
5th 1:1....................180.29mph
6th: .629:1..............(xx rpm @60, will edit later)
Reverse: 2.955:1.

That is f-ing perfect. My biggest gripe on my M3 is the terrible 1-2 upshift; it falls so far out of the peaky powerband that it kills acceleration times (one of the reasons the 7-speed DCT is so much faster, its not just the shift speed, its the ratios). On tracks with slow-speed turns, this is a huge problem and one of the reasons the E9X 6MT doesn't do well in that regard.

 

[arsenalrocks]

ya the e92 1-2 ratio drop is crazy.

That is f-ing perfect. My biggest gripe on my M3 is the terrible 1-2 upshift; it falls so far out of the peaky powerband that it kills acceleration times (one of the reasons the 7-speed DCT is so much faster, its not just the shift speed, its the ratios). On tracks with slow-speed turns, this is a huge problem and one of the reasons the E9X 6MT doesn't do well in that regard.

 

[Grimace427]

What is the rpm @62mph 6th gear?

For some reason the normal calculator I use isn't working, I'll try again when I get home.

 

[Sered]

For comparisons sake:
6MT M3, 8400rpm redline

1st: 4.055:1....42mph
2nd: 2.369:1.....72mph
3rd: 1.582:1.....108mph
4th: 1.192:1.....143mph
5th: 1.000:1.....170mph
6th: 0.872:1.....195mph

Final Drive: 3.846:1

 

[Hack]

Official ratios posted: http://www.mustang6g.com/forums/showthread.php?t=20366

1st: 3.253:1.............55.48mph
2nd: 2:233:1............77.38mph
3rd: 1.611:1.............111.98mph
4th: 1.24:3..............145.4mph
5th 1:1....................180.29mph
6th: .629:1..............(xx rpm @60, will edit later)
Reverse: 2.955:1.

Yuck, wow that is HORRIBLE!

Say you are "racing" this vehicle and go into a corner. You downshift to second. If you can't take the corner faster than ~50 mph you are lugging the engine (or at least you are below the ideal power band of the engine). Crap. Oh well, replacement rear gears aren't too expensive.

 

[Sered]

Yuck, wow that is HORRIBLE!

Say you are "racing" this vehicle and go into a corner. You downshift to second. If you can't take the corner faster than ~50 mph you are lugging the engine (or at least you are below the ideal power band of the engine). Crap. Oh well, replacement rear gears aren't too expensive.

:lol: You should take a look at the M3. There's only so much you can do with 6 gears. The GT350's gear ratios are more like a motorbike, tall 1st but then the rest are pretty close. This is pretty standard for track vehicles. Can't make a perfect gearset for every track; but they could have done A LOT worse.

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