feel of the 3.55's versus the 3.31's
08-11-2011, 03:07 AM
#41
The Paranoid One
Join Date: Apr 2006
Location: Texas
Posts: 5,320
I really don't see the sense in stepping up one gear ratio.
I still say you wont feel much difference.
I would at least take a two step bump if you really are getting them to feel a good difference and get your money's worth. You get used to the new gears with time no matter what but you would probably be disappointed in the feel difference in a one step up and even if you were'nt the wow factor would diminish MUCH faster.
I still say you wont feel much difference.
I would at least take a two step bump if you really are getting them to feel a good difference and get your money's worth. You get used to the new gears with time no matter what but you would probably be disappointed in the feel difference in a one step up and even if you were'nt the wow factor would diminish MUCH faster.
08-11-2011, 09:45 AM
#42
2nd Gear Member
Thread Starter
Join Date: Oct 2010
Location: Washington
Posts: 192
I really don't see the sense in stepping up one gear ratio.
I still say you wont feel much difference.
I would at least take a two step bump if you really are getting them to feel a good difference and get your money's worth. You get used to the new gears with time no matter what but you would probably be disappointed in the feel difference in a one step up and even if you were'nt the wow factor would diminish MUCH faster.
I still say you wont feel much difference.
I would at least take a two step bump if you really are getting them to feel a good difference and get your money's worth. You get used to the new gears with time no matter what but you would probably be disappointed in the feel difference in a one step up and even if you were'nt the wow factor would diminish MUCH faster.
Going 1 step up from a 2.73 to a 3.31 yields about a 21% increase.
Going 3 steps up from a 3.73 to a 4.56 yields about the same (22%)
Going 2 steps up from a 2.73 to a 3.55 yields about a 30% increase
Going 2 steps up from a 3.55 to a 4.10 yields about a 15% increase
See how it's all over the place? One would also have to factor in the ratios relative to zero to factor in issues of diminishing returns, but that subject gets messy, so I'll leave it at that.
Then factor in the crazy gearing of the MT82 in the v6, and you'll see its not like any other gear box that conventional wisdom subscribes to. If we had the gearbox you have, it would be easier to factor in. My position is that the MT82 in the v6 complicates matters.
08-13-2011, 02:08 PM
#44
2nd Gear Member
Thread Starter
Join Date: Oct 2010
Location: Washington
Posts: 192
My point was that the steps mean nothing. Its the difference relative from where you are coming from. Steps isn't the way to measure it. Percentage is. I totally agree with you though that its amazing how fast you get used to it. 2.73 to 3.55 (30%) feels totally natural now just after a couple of weeks.
08-13-2011, 08:02 PM
#45
I follow Sketchy on this one. Feel has nothing to do with selecting the right ratio for a particular purpose. The right ratio might only be one step away. There might not even be a step available from one vendor, where anther vendor has several.
Some typical ratios include 2.73, 3.00, 3.10, 3.23, 3.27, 3.43, 3.55, 3.73, 4.10, 4.88, etc. Look at these and you can see that the "step"s are not even uniform, not by number or by %. Some of these are not readily available for an 8.8".
Selecting the right gear ratio begins with a purpose, or target, like XXXX rpm at the finish line in the 1/4 mile, XXXX rpm at cruising speed (what speed???), XX mph at each shift, etc. Tire size, transmission ratios, number of gears, power output, all play a role. Feel? Not so much.
Some typical ratios include 2.73, 3.00, 3.10, 3.23, 3.27, 3.43, 3.55, 3.73, 4.10, 4.88, etc. Look at these and you can see that the "step"s are not even uniform, not by number or by %. Some of these are not readily available for an 8.8".
Selecting the right gear ratio begins with a purpose, or target, like XXXX rpm at the finish line in the 1/4 mile, XXXX rpm at cruising speed (what speed???), XX mph at each shift, etc. Tire size, transmission ratios, number of gears, power output, all play a role. Feel? Not so much.
08-16-2011, 12:20 AM
#46
Join Date: Jul 2011
Location: California
Posts: 10
Transmission Gear Ratios
I have a reputation for raining on the parade with my friends. I always bring reality, maybe when unwelcome, so here's a litte to consider...
Model-2011____GT500_____GT_____V6
Trans(stick)___TR6060____MT82___MT82
1st___________2.97______3.66____4.17
2nd__________1.78_______2.43____2.34
3rd__________1.30_______1.69____1.52
4th__________1.00_______1.32____1.14
5th__________0.74_______1.00____0.867
6th__________0.50_______0.65____0.691
final_________3.55_______3.31_____2.73
Option_______3.73_______3.55_____3.31
Look closely at the first gear and sixth gear on each one. The V6 is not like any manual transmission to come before it. It basically has a granny gear in 1st to pull that 2.73 decently out of the hole, then it has the .69 overdrive on that 2.73 to get the best mileage. Trying to gear this like a V8 car while only considering the rear gear will take you down a bad road. There is a whopping 25% difference from the 1st gear in the V6 to the first gear in the GT500. There's no way you will enjoy rush hour when you are putting around like a dump truck. Now look at 6th. The GT500 is using a 50% overdrive to cover the 3.73 and get a good highway cruise. That's HUGE! Last thing, now ask yourself if you are going to be running your car at redline in 6th. Short answer is NO. It's very unlikely that a naturally aspirated V^ could pull to redline against real world drag in 6th. If you could, the speed would be enough to get airborn. (watch some Bonneville runs sometime)
If you are thinking about drag racing, you really want to gear so that you come to redline in 3rd at the finish line. Any more shifting and you are giving away time to change gears. Ok, one more, Look at how the option gear is the step up to the ratio of the next power level. Do you really want to jump into GT500 gearing without the power to go with it? Remember those high paid engineer types in Las Vegas and Detroit?
OK, I'll shut up now.
Model-2011____GT500_____GT_____V6
Trans(stick)___TR6060____MT82___MT82
1st___________2.97______3.66____4.17
2nd__________1.78_______2.43____2.34
3rd__________1.30_______1.69____1.52
4th__________1.00_______1.32____1.14
5th__________0.74_______1.00____0.867
6th__________0.50_______0.65____0.691
final_________3.55_______3.31_____2.73
Option_______3.73_______3.55_____3.31
Look closely at the first gear and sixth gear on each one. The V6 is not like any manual transmission to come before it. It basically has a granny gear in 1st to pull that 2.73 decently out of the hole, then it has the .69 overdrive on that 2.73 to get the best mileage. Trying to gear this like a V8 car while only considering the rear gear will take you down a bad road. There is a whopping 25% difference from the 1st gear in the V6 to the first gear in the GT500. There's no way you will enjoy rush hour when you are putting around like a dump truck. Now look at 6th. The GT500 is using a 50% overdrive to cover the 3.73 and get a good highway cruise. That's HUGE! Last thing, now ask yourself if you are going to be running your car at redline in 6th. Short answer is NO. It's very unlikely that a naturally aspirated V^ could pull to redline against real world drag in 6th. If you could, the speed would be enough to get airborn. (watch some Bonneville runs sometime)
If you are thinking about drag racing, you really want to gear so that you come to redline in 3rd at the finish line. Any more shifting and you are giving away time to change gears. Ok, one more, Look at how the option gear is the step up to the ratio of the next power level. Do you really want to jump into GT500 gearing without the power to go with it? Remember those high paid engineer types in Las Vegas and Detroit?
OK, I'll shut up now.
1st 4.236
2nd 2.538
3rd 1.665
4th 1.238
5th 1.00
6th 0.70
Final drive 2.73 or 3.31
On a side note, I used to drive a 69 Fairlane with a built 302 that redlined at just under 7k rpm. The c4 transmission and rear-end gears were:
1st 2.46:1
2nd 1.46:1
3rd 1.00:1
Final drive 3.80
The power numbers are similar for both cars. The major subjective difference is that the Fairlane felt way faster off-the-line than the rental car I test drove. That thing startled me sometimes when I was taking off. I didn’t get that feeling with the Mustang until about 15-20 mph in first gear. The numbers don’t seem to add up. The Fairlane was a little lighter, and the engine torquier down low, but the 4.17 1st gear should more than offset that, even with 2.73 rear gears (Fairlane-3.80x2.46=6.888 and Mustang-4.17x2.73=11.3841, a 68% increase).
Am I crazy here, or is there something I’m missing? Am I calculating the ratios wrong? Maybe it’s the stall on the torque converter. I think I was running a 2700 rpm stall in the C4. Anyone know what the stall rpm is in the 2011 Mustang automatic? Also, does anyone know how much difference the manual transmission makes in how it feels in off-the-line acceleration? A manual wasn’t available when I test drove, and I’m definitely getting that version.
08-16-2011, 01:17 AM
#47
It's hard to compare manual to auto with the butt dyno. The manual feels dramatic because, launched well, it leaves harder than an auto. The close ratio of the six speed manual makes you shift sooner than the wide ratio in the auto that really gets some help from the torque converter once the slippage is out of the way and you exceed stall speed. The converter actually multiplies torque a bit to make it pull harder, but it's the slip at the start that hides that.
You're right about the ratios. That 6 speed auto confuses a lot. I think I knew that but never edited it.
You're right about the ratios. That 6 speed auto confuses a lot. I think I knew that but never edited it.
08-16-2011, 08:30 PM
#49
2nd Gear Member
Join Date: Jan 2010
Location: New York
Posts: 237
they came out awesome. Mike @ Snake Pit Performance did an outstanding job installing the gears, and I have no whine what so ever. Besides the install being done properly I also believe this is due to the bearing kit Mike made me get. The pinion bearing is hard to get off and most of the time they break when taking them off. Also my crush sleeves were worn unevenly from the factory. Everything new was put in, shims, bearings, seals, crush sleeves, ect.. The pinion depth and the backlash were set perfectly and the rear is sealed perfectly.
Driving impressions:
We'll coming from 2.73's and going to 3.55's ford made my first gear very short to get the car rolling with the 2.73s. With the 3.55's first gear is over very quickly lol. I can even start the car in second gear if I want, but realistically its not a bad start in first, its just going to take some time to get used to it. Every other gear feels like there is so much power, and yet I am still not reving the **** out of my car on the highway. 6th gear I am taching right around 2k rpms @ 60mph. Not bad at all, matter a fact I got 27 mpg on the way home and that was still getting on the car a little bit. 6th gear with the 2.73's was useless, it was to tall and the car felt like it would loose momentum after awhile and you'd have to switch into 5th constantly.
Anyways I feel I made the right choice with this whole situation, and I would recommend many others to do the same after my experience.
Ford Racing Gears (bought them on AM)
3 quarts of royal purple 90w140 gear oil
Yukon Bearing/hardware kit
Snake Pit Performance (Long Island, NY) install
= a great turn out and best bang for the buck performance wise.
Can't wait till the 500 mile break in so I can change the gear oil and see what my car really feels like.
Driving impressions:
We'll coming from 2.73's and going to 3.55's ford made my first gear very short to get the car rolling with the 2.73s. With the 3.55's first gear is over very quickly lol. I can even start the car in second gear if I want, but realistically its not a bad start in first, its just going to take some time to get used to it. Every other gear feels like there is so much power, and yet I am still not reving the **** out of my car on the highway. 6th gear I am taching right around 2k rpms @ 60mph. Not bad at all, matter a fact I got 27 mpg on the way home and that was still getting on the car a little bit. 6th gear with the 2.73's was useless, it was to tall and the car felt like it would loose momentum after awhile and you'd have to switch into 5th constantly.
Anyways I feel I made the right choice with this whole situation, and I would recommend many others to do the same after my experience.
Ford Racing Gears (bought them on AM)
3 quarts of royal purple 90w140 gear oil
Yukon Bearing/hardware kit
Snake Pit Performance (Long Island, NY) install
= a great turn out and best bang for the buck performance wise.
Can't wait till the 500 mile break in so I can change the gear oil and see what my car really feels like.
08-17-2011, 11:37 PM
#50
Join Date: Sep 2006
Location: Heidelberg, Germany
Posts: 31
Thanks for the info BLUE.
I may go this route as well. I need to cruise @ 80MPH for 6th gear to be useable without lugging. So most of the time I am in 5th gear betweem 65MPH and 75MPH. If the 3.55s put me at 2000 RPMs at 60MPH I will be happy. I will ultimately burn less fuel because I will not constantly downshift and wind the motor up in 4th gear to pass a car. 6th gear is useless with 2.73s even on the autobahn.
I may go this route as well. I need to cruise @ 80MPH for 6th gear to be useable without lugging. So most of the time I am in 5th gear betweem 65MPH and 75MPH. If the 3.55s put me at 2000 RPMs at 60MPH I will be happy. I will ultimately burn less fuel because I will not constantly downshift and wind the motor up in 4th gear to pass a car. 6th gear is useless with 2.73s even on the autobahn.