3.73 vs 3.08: Better gearing choice??
8/29/11, 07:15 PM
#22
40mph isn't useless, it's the short gap between 1st to 2nd that's really useless w/3.73's. To be honest, it all depends on how you want to drive your car. I want to drive my Mustang like an automatic when I'm not using the car in a performance manner, and the easiest way to accomplish that is to shift as little as possible, taking advantage of the Torque instead of the HP and RPM's.
An automatic shifts quickly, keeping the revs/noise down while simultaneously keeping your car steadily pulling away from a stop light. You simply can't do that quickly enough while trying to use every gear in a manual 5.0 w/3.73's and shift at a moderate 2000-2500 rpm's, like an automatic would, and maintain the speed all the traffic around you is moving.
Where I live the speed limits on most roads is 40-55, and traffic accelerates pretty quickly around here, so unless you rev up on first pretty hard, traffic just moves on by you, and I hate being a road-block simply because I couldn't keep pace with the traffic w/o revving the engine like rice boy racer.
I think I'm going to get the 3.08's installed in a month or so. It won't be the end of the world, and if I don't like it, I can always get the original 3.73's put right back in.
Here is a 3.08 6spd-manual compared to the stock 3.15 6spd-automatic, and then both 3.7L V6's in manual and auto:
3.08 manual @ 6800 rpms
1 = 48 mph
2 = 73 mph
3 = 105 mph
4 = 134 mph
5 = 177 mph
6 @ 80mph = 2000 rpm
3.15 auto @ 6800 rpms
1 = 41 mph
2 = 74 mph
3 = 114 mph
4 = 152 mph
5 = 199 mph
6 @ 80mph = 2175 rpm
2.73 manual 3.7L V6 @ 6850 rpms
1 = 47 mph
2 = 79 mph
3 = 121mph
4 = 162 mph
5 = 201 mph
6 @ 80mph = 1900 rpm
2.73 auto 3.7L V6 @ 6850 rpms
1 = 48 mph
2 = 86 mph
3 = 132 mph
4 = 176 mph
5 = 232 mph
6 @ 80mph = 1900 rpm
You don't hear many automatic people complaining that the gearing of the stock 5.0L automatic is horrible, and their drag strip times don't reflect horrible performance either. 3.08's in a 5.0L manual car would still be shorter than a 5.0L automatic with 3.15's (exception of 1st gear), and is still even shorter gearing than the 3.7L V6 automatic or manual car with 2.73's.
FYI - the Corvette Z06 is capable of 59mph in 1st gear, and the ZR1 can do 68mph in 1st. (I know they are lighter and more powerful than the Mustang)
An automatic shifts quickly, keeping the revs/noise down while simultaneously keeping your car steadily pulling away from a stop light. You simply can't do that quickly enough while trying to use every gear in a manual 5.0 w/3.73's and shift at a moderate 2000-2500 rpm's, like an automatic would, and maintain the speed all the traffic around you is moving.
Where I live the speed limits on most roads is 40-55, and traffic accelerates pretty quickly around here, so unless you rev up on first pretty hard, traffic just moves on by you, and I hate being a road-block simply because I couldn't keep pace with the traffic w/o revving the engine like rice boy racer.
I think I'm going to get the 3.08's installed in a month or so. It won't be the end of the world, and if I don't like it, I can always get the original 3.73's put right back in.
Here is a 3.08 6spd-manual compared to the stock 3.15 6spd-automatic, and then both 3.7L V6's in manual and auto:
3.08 manual @ 6800 rpms
1 = 48 mph
2 = 73 mph
3 = 105 mph
4 = 134 mph
5 = 177 mph
6 @ 80mph = 2000 rpm
3.15 auto @ 6800 rpms
1 = 41 mph
2 = 74 mph
3 = 114 mph
4 = 152 mph
5 = 199 mph
6 @ 80mph = 2175 rpm
2.73 manual 3.7L V6 @ 6850 rpms
1 = 47 mph
2 = 79 mph
3 = 121mph
4 = 162 mph
5 = 201 mph
6 @ 80mph = 1900 rpm
2.73 auto 3.7L V6 @ 6850 rpms
1 = 48 mph
2 = 86 mph
3 = 132 mph
4 = 176 mph
5 = 232 mph
6 @ 80mph = 1900 rpm
You don't hear many automatic people complaining that the gearing of the stock 5.0L automatic is horrible, and their drag strip times don't reflect horrible performance either. 3.08's in a 5.0L manual car would still be shorter than a 5.0L automatic with 3.15's (exception of 1st gear), and is still even shorter gearing than the 3.7L V6 automatic or manual car with 2.73's.
FYI - the Corvette Z06 is capable of 59mph in 1st gear, and the ZR1 can do 68mph in 1st. (I know they are lighter and more powerful than the Mustang)
With all due respect, after reading that post it sounds like you should have bought an automatic.
8/29/11, 09:05 PM
#24
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Sometimes performance cars can be made into good all-around performers and daily drivers. I'm also seeking to gain a little more top speed capability.
I guess if I decide to do this in a few months, I will have to get some street slicks and head to the track, dyno, and track mileage numbers and overall experiences for some before and after results. If my experiment ends in dismal failure, which it could, I fully intend to put 3.55 or 3.73's back in the car.
I guess if I decide to do this in a few months, I will have to get some street slicks and head to the track, dyno, and track mileage numbers and overall experiences for some before and after results. If my experiment ends in dismal failure, which it could, I fully intend to put 3.55 or 3.73's back in the car.
8/29/11, 09:13 PM
#25
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yeah, I think with this gear set it runs outta snot @~150
I've a cousin who's like a brother named Kelly and you're driving a good lookin car so...I'll quit messin' with you
Arlington...heard you all got a little rain
I've a cousin who's like a brother named Kelly and you're driving a good lookin car so...I'll quit messin' with you
Arlington...heard you all got a little rain
8/29/11, 09:26 PM
#26
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To be honest, I've been asking myself the same question as the OP with respect to track use. 1st is completely useless unless I'd be doing standing starts. The F2000's I used to drive had a very tall 1st gear too, they were geared to pull well off the hairpin in 1st. I could trade off the line for top end speed (and economy to and from the track).
If running a taller rear gear and using a lower trans gear would give the same overall ratio, then performance should actually increase, since less power would be absorbed to spin up the drive shaft.
If running a taller rear gear and using a lower trans gear would give the same overall ratio, then performance should actually increase, since less power would be absorbed to spin up the drive shaft.
Last edited by PTRocks; 8/29/11 at 09:30 PM.
8/29/11, 09:28 PM
#27
Originally Posted by PTRocks
To be honest, I've been asking myself the same question as the OP with respect to track use. 1st is completely useless unless I'd be doing standing starts. The F2000's I used to drive had a very tall 1st gear too, they were geared to pull well off the hairpin in 1st. I could trade off the line for top end speed (and economy to and from the track).
8/29/11, 09:43 PM
#28
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It may be, I really need an Excel sheet of someone's stock dyno pull to do the gear chart.
I gotta choose asap too, as my car needs a new ring and pinion, under warranty.
I gotta choose asap too, as my car needs a new ring and pinion, under warranty.
Last edited by PTRocks; 8/29/11 at 10:02 PM.
8/29/11, 10:33 PM
#30
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I have personally owned modern V8 Mustangs with the following axle ratios: 2.73, 3.27, 3.31, 3.55, 3.73, 4.10, and 4.30. So, I have first hand experience with most every popular gear ratio available in the 8.8" rear ends.
My Mustangs have always been daily drivers - mostly in town driving with some highway miles - and they've been drag raced occasionally.
For my driving style (as noted above) I found the 2.73's to be absolutely worthless and unsatisfying in all respects. The 3.27's and 3.31's were luke warm and barely passable for any fun. The 3.55's and 3.73's were okay for all around performers & decent economy. The 4.10's and 4.30's were the absolute most entertaining while barely degrading my fuel economy. I have been seriously considering putting 4.56's in my '11 5.0L as I find more gearing makes driving much more pleasurable!
As the old adage goes: Don't Fear the Gear!
My Mustangs have always been daily drivers - mostly in town driving with some highway miles - and they've been drag raced occasionally.
For my driving style (as noted above) I found the 2.73's to be absolutely worthless and unsatisfying in all respects. The 3.27's and 3.31's were luke warm and barely passable for any fun. The 3.55's and 3.73's were okay for all around performers & decent economy. The 4.10's and 4.30's were the absolute most entertaining while barely degrading my fuel economy. I have been seriously considering putting 4.56's in my '11 5.0L as I find more gearing makes driving much more pleasurable!
As the old adage goes: Don't Fear the Gear!
8/29/11, 10:47 PM
#31
I will buy Jack Stands!!!
40mph isn't useless, it's the short gap between 1st to 2nd that's really useless w/3.73's. To be honest, it all depends on how you want to drive your car. I want to drive my Mustang like an automatic when I'm not using the car in a performance manner, and the easiest way to accomplish that is to shift as little as possible, taking advantage of the Torque instead of the HP and RPM's.
An automatic shifts quickly, keeping the revs/noise down while simultaneously keeping your car steadily pulling away from a stop light. You simply can't do that quickly enough while trying to use every gear in a manual 5.0 w/3.73's and shift at a moderate 2000-2500 rpm's, like an automatic would, and maintain the speed all the traffic around you is moving.
Where I live the speed limits on most roads is 40-55, and traffic accelerates pretty quickly around here, so unless you rev up on first pretty hard, traffic just moves on by you, and I hate being a road-block simply because I couldn't keep pace with the traffic w/o revving the engine like rice boy racer.
An automatic shifts quickly, keeping the revs/noise down while simultaneously keeping your car steadily pulling away from a stop light. You simply can't do that quickly enough while trying to use every gear in a manual 5.0 w/3.73's and shift at a moderate 2000-2500 rpm's, like an automatic would, and maintain the speed all the traffic around you is moving.
Where I live the speed limits on most roads is 40-55, and traffic accelerates pretty quickly around here, so unless you rev up on first pretty hard, traffic just moves on by you, and I hate being a road-block simply because I couldn't keep pace with the traffic w/o revving the engine like rice boy racer.
Secondly, F the people behind you, they can wait. If they don't like it, they can pass you.
Oh yeah, I have 3.08s in my truck, if your 'stang runs an 8.8 diff I'll trade you straight up for your 3.73s
Last edited by mustangGT90210; 8/29/11 at 10:49 PM.
8/29/11, 11:04 PM
#32
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3.55s in a 5.0 with the m82 will be simular to having 4.10s in 1st with the 4.6 & the tr 3560. 6th would be like having the 3.38s out back. That plus the added torque of the 5.0 seems to me to be the best of both worlds. Its what I am going with when I upgrade.
Last edited by Cusp; 8/29/11 at 11:09 PM.
9/3/11, 10:56 PM
#33
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I can't believe no one has posted this but.... If you have the 3.73's it tells you on the dash display to shift from 1st to 4th for fuel economy. I have a 2012 5.0 with 3.73's and I shift out if first at around 2500rpm straight in to 4th and shift out of 4th at 1500-2000rpm and straight to 6th. Three gear changes and if you shift at 2000 out of first and 1500 out of 4th then when you hit 6th you are at about 40-45mph. If you shift at 2500-3000 out if first in to 4th and then at 2000 out of 4th in to 6th you will be around 55-60mph. I have been doing this for the last few weeks I have owned the car and with 40% city driving and 60% highway at 60mph I get 25.6 mpg per tank. And that is calculating it myself and not going by the computers average miles per gallon.
9/4/11, 11:24 AM
#34
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9/4/11, 12:27 PM
#35
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Originally Posted by HoosierDaddy
Aren't you talking about the skip shift "feature" of all MT GTs?
9/4/11, 05:19 PM
#37
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Was searching around and found this posted from Sam Strano:
https://themustangsource.com/newrepl...eply&p=5935370
https://themustangsource.com/newrepl...eply&p=5935370
My car is a 3.31 car because anything else would be too short and force me into 3rd gear when autocrossing on my Hoosiers. In fact the 3.73 is super short on stock tires, something like 60 mph max. Funny part is when you watch the video from Motor Trend you can see the M3 pull the Mustang because it's shifting so much. And I hear that they need 5th at the end of the 1/4. I think 3.73 is a hype setup more than anything and that 3.55 is probably the better drag gear. And I've very happy with my 3.31 for corner carving.
9/5/11, 12:56 AM
#38
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If I were to do it again I'd go for the 3.55's instead of the 3.73's... I'd be less busy while driving around town and based on the power I've felt it would be ok at the road courses still, and might even help in a couple turns where I wouldn't be between gears.
9/5/11, 12:57 AM
#39
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Gears are a torque multiplier by definition. The GM V8's are much bigger engines that make more torque than our 5.0L, so they can get away with less gearing without hurting acceleration. The high-revving 5.0L Ford needs gearing to make up for the lack of torque.
That said, the 3.08's will make the car feel like a turd, 1/4 mile times will suffer drastically, and fuel economy on the highway will barely improve, while fuel economy around town will suffer as you'll need more throttle to get the car moving.
That said, the 3.08's will make the car feel like a turd, 1/4 mile times will suffer drastically, and fuel economy on the highway will barely improve, while fuel economy around town will suffer as you'll need more throttle to get the car moving.
9/5/11, 04:12 AM
#40
Was searching around and found this posted from Sam Strano:
https://themustangsource.com/newrepl...eply&p=5935370
https://themustangsource.com/newrepl...eply&p=5935370
