Need Experts Opinion on Why should someone change rearend gears
02-13-2007, 04:10 AM
#1
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Need Experts Opinion on Why should someone change rearend gears
I have been having a debate on another forum with a new mustang owner about gears, He is young and cocky, thinks he knows it all.
Here are some of his comments:
I have explained every which way I can but I have not explained it well enough, i guess. Any ideas, info
He has a 5-spd Manual 2007 Mustang GT (I think he has the 3.31 that Ford has made the standard in 07but I am only assuming this. he could very well have 3.55 like the 05-06 5spd's. So calling all experts..
Here are some of his comments:
Dude, gears are a waste of time. You are not getting any gain by going to a different gear set. Sure, one gear set will get you to 60 faster than another, but at what cost ???? GAS ?? Stick with what you have from Ford and look at other modds. Gears are waaaaay overrated. Oh, and I forgot to mention, gears DO not give you more HP ! They simply spread the powerband delivery to other gears. STUPID ! not worth it
"OKAY...If the 4.10 is better..why the hell didn’t Ford just make that the GT standard ? There is zero cost involved in that decision. They did it because the 4.10 is inferior. I know, I beat it with my factory gear. Learn to drive/shift, that is key.."
INferior for gas and for god knows what other reason. Learn the art of shifting..and spend your hard earned mod $ on other, better upgrades. Okay, I a very biased against the gear work...always have been. 07 pointed out that you gain zero HP..you just spread the power to other gears. There are soooo many other things to do.
He has a 5-spd Manual 2007 Mustang GT (I think he has the 3.31 that Ford has made the standard in 07but I am only assuming this. he could very well have 3.55 like the 05-06 5spd's. So calling all experts..
02-13-2007, 05:28 AM
#2
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Join Date: May 2005
Location: Groesbeck, TX
Posts: 361
RE: Need Experts Opinion on Why should someone change rearend gears
OK, only thing I see right is gears don't make horsepower and it will hurt your fuel mileage. That is the real reason Ford doesn't go to a higher gear, fuel mileage. Nowadays they wouldn't sell as many cars if the mileage was in the teens. Well at least not to non car nuts.
It will help you launch and accelerate faster. If you're looking at 1/4 times, you'll want bigger gears. If you want highway mileage or higher top speed, smaller gears.
I'm still trying to figure out the part about spreading out the powerband delivery to other gears. You got gears in your axels?
It will help you launch and accelerate faster. If you're looking at 1/4 times, you'll want bigger gears. If you want highway mileage or higher top speed, smaller gears.
I'm still trying to figure out the part about spreading out the powerband delivery to other gears. You got gears in your axels?
02-13-2007, 07:14 AM
#3
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RE: Need Experts Opinion on Why should someone change rearend gears
Sometimes you just have to know when to quit on the interenet. Some people are just morons and you can't convince them of anything no matter what info you provide them. Bottom line is gears are probably THE most cost effective mod for track times you can get. Yes fuel economy goes down but if you are modding a mustang I doubt that is a motivator in any of your decisions.
Look I would just ignore the dude because he obviously doen'st know what he's talking about and isn't about to change his opinion. Even of you proved to him that your 1/4 mile times were better he would just say "well thats not much of a gain"
You're wasting your time just ignore him.
Look I would just ignore the dude because he obviously doen'st know what he's talking about and isn't about to change his opinion. Even of you proved to him that your 1/4 mile times were better he would just say "well thats not much of a gain"
You're wasting your time just ignore him.
02-13-2007, 10:07 AM
#4
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RE: Need Experts Opinion on Why should someone change rearend gears
ORIGINAL: rattsj
Sometimes you just have to know when to quit on the interenet. Some people are just morons and you can't convince them of anything no matter what info you provide them. Bottom line is gears are probably THE most cost effective mod for track times you can get. Yes fuel economy goes down but if you are modding a mustang I doubt that is a motivator in any of your decisions.
Look I would just ignore the dude because he obviously doen'st know what he's talking about and isn't about to change his opinion. Even of you proved to him that your 1/4 mile times were better he would just say "well thats not much of a gain"
You're wasting your time just ignore him.
Sometimes you just have to know when to quit on the interenet. Some people are just morons and you can't convince them of anything no matter what info you provide them. Bottom line is gears are probably THE most cost effective mod for track times you can get. Yes fuel economy goes down but if you are modding a mustang I doubt that is a motivator in any of your decisions.
Look I would just ignore the dude because he obviously doen'st know what he's talking about and isn't about to change his opinion. Even of you proved to him that your 1/4 mile times were better he would just say "well thats not much of a gain"
You're wasting your time just ignore him.
02-13-2007, 11:06 AM
#5
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Join Date: Aug 2006
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RE: Need Experts Opinion on Why should someone change rearend gears
Gears are a waste of time, for what you get and the possibility you just ruined your brand new rear for marginal gain and lets not forget if you have loud exhaust good luck driving on the high way and get a second job for all the gas you will use and oh yea, it puts more wear on your engine for no reason. As you own your car longer and add more power adders, you will reach a point where the gears hurt you becasue you won't be able to hook up.
02-13-2007, 11:34 AM
#6
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RE: Need Experts Opinion on Why should someone change rearend gears
Gears do not kill your gas all the time. In the city it gives you a mechanical advantage, which puts less strain on the motor, less strain means less gas involved. Unless you floor it all the time from a redlight. Highway driving, i've known people to gain 1-2mpg or lost 1-2mpg with a gear swap. Depends on your driving habits.
Gears are the best bang for buck. 5.0 and MMFF's will tell you the samething, and i don't think they are dumb at all. I've had 4.10's and BBK shorty heads, BBK Hpipe, and Flowasters on my 95 GT and i didn't mind it at all on the highway. Also gears will add a little more wear to the engine, by adding around 300rpms more to what you normally have, saying cruising at 80mph in 5th gear. That's a slight amount of wear and also, it depends on your driving habits. I can have 3.08 gears and beat the sh*t out of my car and cause wear and tear on the motor.
With a power adder 3.73's or 4.10's wont hurt, people run those gears with nitrous or FI all the time. Some people don't like hitting the traps at a certain rpms so they step now to either 3.55's or 3.73's. Some people love a power adder and 4.10's and wouldn't have it any other way. Now if you wanted FI or nitrous and 4.56 gears, i would think that's a tad to much.
Gears are great and you will tell a difference, unless you go from like 3.55 to 3.73's you won't tell to much of a difference. From 3.55 to 4.10's you will definitely feel al difference. Usually over .20 gain or more you will feel a difference.
Gears are the best bang for buck. 5.0 and MMFF's will tell you the samething, and i don't think they are dumb at all. I've had 4.10's and BBK shorty heads, BBK Hpipe, and Flowasters on my 95 GT and i didn't mind it at all on the highway. Also gears will add a little more wear to the engine, by adding around 300rpms more to what you normally have, saying cruising at 80mph in 5th gear. That's a slight amount of wear and also, it depends on your driving habits. I can have 3.08 gears and beat the sh*t out of my car and cause wear and tear on the motor.
With a power adder 3.73's or 4.10's wont hurt, people run those gears with nitrous or FI all the time. Some people don't like hitting the traps at a certain rpms so they step now to either 3.55's or 3.73's. Some people love a power adder and 4.10's and wouldn't have it any other way. Now if you wanted FI or nitrous and 4.56 gears, i would think that's a tad to much.
Gears are great and you will tell a difference, unless you go from like 3.55 to 3.73's you won't tell to much of a difference. From 3.55 to 4.10's you will definitely feel al difference. Usually over .20 gain or more you will feel a difference.
02-13-2007, 11:38 AM
#7
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RE: Need Experts Opinion on Why should someone change rearend gears
Way to many threads about this subject. Just Do It ! You'll get there alot quicker. If you cant afford the gas like ba ba barbarino you shouldn't be adding mods.
02-13-2007, 12:11 PM
#8
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RE: Need Experts Opinion on Why should someone change rearend gears
This guy is right, gears do not give you more HP. BUT, gears do transfer more torque to the rear axle of the car and thus make you accelerate harder.
Gears are exactly like a lever. Along lever makes it easier to move a heavy load. But just like a lever, the more mechanical advantage you gain, the more you have to move your end of the lever for the same output. This is the RPM increase that gears have.
This means that under highway conditions gears can cost you a little mileage. In my case, switching from stock to 4.30s cost me about 1.5 MPG on the highway. (Note that I have bigger rear tires, so my 4.30's are equivalent to 4.10 on normally sized tires). That was a trivial cost to me.
As for city mileage, often times gears don't hurt at all. This is becasue you can always drive in a higher gear on your transmission. Think about it: With the stock setup in city streets around 20-40 MPH you will spend a lot of time in second and third, maybe 4th. If you swap in some lower gears, you can simply drive in third and forth more often (and perhaps even 5th). The net result is that during normal driving in the city, your final drive ratio will be about the same. My city mileage did NOT change at all with my gear swap.
Regarding the comment about the power adder...I think there is a little truth to that. As I mentioned above, I'm running 4.30's right now (equiavlent to 4.10 on stock tires). With my mods I'm putting down about 330 to the ground, and it is perfectly driveable. Later this year I will be dropping in a new engine and/or a SC (plans not finalized yet) alongside a T-56. At that point I will be switching back to some taller gears becasue I don't want first and second to be totally useless. I will have to crunch the actual numbers, but I will probably be looking at somewhere in the 3.73-4.10 range. 4.30s plus that kind of torque would be a handful. BUT, for the average guy who has bolt ons and doesn't have a stroker motor orFI, there isn't much to worry about. A basic suspension setup will have you hooking up great even with low gears.
Gears are exactly like a lever. Along lever makes it easier to move a heavy load. But just like a lever, the more mechanical advantage you gain, the more you have to move your end of the lever for the same output. This is the RPM increase that gears have.
This means that under highway conditions gears can cost you a little mileage. In my case, switching from stock to 4.30s cost me about 1.5 MPG on the highway. (Note that I have bigger rear tires, so my 4.30's are equivalent to 4.10 on normally sized tires). That was a trivial cost to me.
As for city mileage, often times gears don't hurt at all. This is becasue you can always drive in a higher gear on your transmission. Think about it: With the stock setup in city streets around 20-40 MPH you will spend a lot of time in second and third, maybe 4th. If you swap in some lower gears, you can simply drive in third and forth more often (and perhaps even 5th). The net result is that during normal driving in the city, your final drive ratio will be about the same. My city mileage did NOT change at all with my gear swap.
Regarding the comment about the power adder...I think there is a little truth to that. As I mentioned above, I'm running 4.30's right now (equiavlent to 4.10 on stock tires). With my mods I'm putting down about 330 to the ground, and it is perfectly driveable. Later this year I will be dropping in a new engine and/or a SC (plans not finalized yet) alongside a T-56. At that point I will be switching back to some taller gears becasue I don't want first and second to be totally useless. I will have to crunch the actual numbers, but I will probably be looking at somewhere in the 3.73-4.10 range. 4.30s plus that kind of torque would be a handful. BUT, for the average guy who has bolt ons and doesn't have a stroker motor orFI, there isn't much to worry about. A basic suspension setup will have you hooking up great even with low gears.
02-13-2007, 12:37 PM
#9
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RE: Need Experts Opinion on Why should someone change rearend gears
so a guy with a V6 should go up to what? Not looking to win races or take it to the strip, just looking for a little more punch. Im not really sure what ratio i have now in the V6, is it 3.55 or 3.2something? Also what would the cost be to go to 3.73 or something, would it be worth it?
02-13-2007, 12:38 PM
#10
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RE: Need Experts Opinion on Why should someone change rearend gears
Oh Beleive me, I know the benifits and pit falls of gear changes, I used to build Race cars in the early 80's
I just can't express my thoughts clearly enough to this guy.. I guess he is just dead set against gears
This was my response to him:
I just can't express my thoughts clearly enough to this guy.. I guess he is just dead set against gears
This was my response to him:
Gears give you the most performance bang-for-the-buck. heres why.
Lets make things simple:
Rule of thumb:
Manual/Stick go for the 3.73's or the 4.10's for more aggressive driving
Auto do 4.10's.
(the higher the gear ratio...the higher rpms will be at a given speed. Say for example you are in 4th gear doing 65mph and at 2200rpms with your stock gears...3.73's may push it to 2700rpms....and 4.10s may go to 3000rpms) ***JUST EXAMPLE....not accurate***
** Please do not ask about "gas mileage" when changing gears. If you are worried about that, then do NOT modify your mustang. PLUS it only effects the mpg IN A SLIGHT MANOR" The 07 Mustangs are coming standard with 3.31 gears to meet new EPA fuel standards (you can order 3.55 or 3.73 if you order your car) 3.55 and 3.73 are considered "performance gears" 3.40 or below are so called "highway gears" 4.10 are Street / Track Gears (weekend racer) 4.30+ Serious Drag Racer gears.
What do gears do? Basically the change the ratio in the rear end. So
let’s get into why one would want to change rear-axle ratios. The short answer is that by installing a lower rear gear (higher numerically), mechanical advantage is increased, which makes acceleration Faster and easier. The downside to this is the engine has to do more revolutions to move the vehicle the same amount of distance versus a taller gear – this leads to decreased fuel mileage and lower top speeds. Installing taller gears (lower numerically) typically results in better fuel mileage and higher top speed. For street vehicles, top speeds aren’t really an issue since max highway speeds are 65mph, so you’re left with lackadaisical acceleration with a tall gear.
In essense lower gears makes your rpms raise up much faster. Meaning when you take off in first gear you can rest assured in about 1-2 seconds 1st gear will be GONE and you will be going into 2nd gear. Now why would that be good? Well 2nd and 3rd gears are your POWER gears....so putting on gears allows you to reach what they call the "POWER BAND" much faster. Reaching the power band allows your mustang to get going a bit faster.
Remember that gears do NOT add horsepower to your mustang...they add traction abilities. They allow your mustang to get to the MAX power faster. SO the more mods you add with gears the BETTER the outcome.
05-07 Mustangs need to get a programmer to reprogram their computer. There are many types of reprogrammers to pick from and run about $400 each one. But this will allow you to fix the speedometer and will also remove the rev limiter and allow for small adjustments to allow the car to pick up more acceleration/power, etc.
Recap:
Gears make rpms go faster, letting you get the POWER in your stang faster.
Not an easy mod to do yourself but an AMAZING one on the mustang. You will NOT regret getting gears.....believe me
Lets make things simple:
Rule of thumb:
Manual/Stick go for the 3.73's or the 4.10's for more aggressive driving
Auto do 4.10's.
(the higher the gear ratio...the higher rpms will be at a given speed. Say for example you are in 4th gear doing 65mph and at 2200rpms with your stock gears...3.73's may push it to 2700rpms....and 4.10s may go to 3000rpms) ***JUST EXAMPLE....not accurate***
** Please do not ask about "gas mileage" when changing gears. If you are worried about that, then do NOT modify your mustang. PLUS it only effects the mpg IN A SLIGHT MANOR" The 07 Mustangs are coming standard with 3.31 gears to meet new EPA fuel standards (you can order 3.55 or 3.73 if you order your car) 3.55 and 3.73 are considered "performance gears" 3.40 or below are so called "highway gears" 4.10 are Street / Track Gears (weekend racer) 4.30+ Serious Drag Racer gears.
What do gears do? Basically the change the ratio in the rear end. So
let’s get into why one would want to change rear-axle ratios. The short answer is that by installing a lower rear gear (higher numerically), mechanical advantage is increased, which makes acceleration Faster and easier. The downside to this is the engine has to do more revolutions to move the vehicle the same amount of distance versus a taller gear – this leads to decreased fuel mileage and lower top speeds. Installing taller gears (lower numerically) typically results in better fuel mileage and higher top speed. For street vehicles, top speeds aren’t really an issue since max highway speeds are 65mph, so you’re left with lackadaisical acceleration with a tall gear.
In essense lower gears makes your rpms raise up much faster. Meaning when you take off in first gear you can rest assured in about 1-2 seconds 1st gear will be GONE and you will be going into 2nd gear. Now why would that be good? Well 2nd and 3rd gears are your POWER gears....so putting on gears allows you to reach what they call the "POWER BAND" much faster. Reaching the power band allows your mustang to get going a bit faster.
Remember that gears do NOT add horsepower to your mustang...they add traction abilities. They allow your mustang to get to the MAX power faster. SO the more mods you add with gears the BETTER the outcome.
05-07 Mustangs need to get a programmer to reprogram their computer. There are many types of reprogrammers to pick from and run about $400 each one. But this will allow you to fix the speedometer and will also remove the rev limiter and allow for small adjustments to allow the car to pick up more acceleration/power, etc.
Recap:
Gears make rpms go faster, letting you get the POWER in your stang faster.
Not an easy mod to do yourself but an AMAZING one on the mustang. You will NOT regret getting gears.....believe me