Installing New Gears?

[Weapon_R]

What does it mean when someone installs new gears? I've been reading in another thread, that mustangs have more power with a 3.73 setup etc. What is required to do this? Where do these gears go?

[Ekliptix]

In the rear differential. Say, for example a rwd car comes with 3.73 gears, and then has 4.10 gears installed, he will accelerate faster, but have a lower top speed.

I think that something like a 95 Camaro Z28 will lose 3/10th's in the 1/4 mile if they do this. They can still keep a decent cruizing rpm too, because of having a 6-speed (maybe it's only the SS's, i can't remember).

[Weapon_R]

What is the point of it, if it slows you down?

[B18C]

it's really a compramise. When you have say 3.73 gears, you will have a higher top speed but your gearing will be taller. If you swap those out for 4.10 gears you will have shorter gears (accelerate faster), but your top speed will not be as high. Also, with taller gears, you will tend to get better gas mileage, especially on the highway.

[Weapon_R]

So is installing taller gears sort of like engaging an overdrive?

And how hard/expensive is it to install taller gears?

[Ekliptix]

I don't think that overdrive comment is right, but it's easy to do on Rwd cars but probably a lot harder to do on Fwd. I don't recommend it on your honda/acura unless you plan to go to the drag strip everyday.
I know that some people with Integra's put in the ys1 transmition from GSR's but leave the 5th gear as the LS version. This gives them better acceleration plus an ok cruizing rpm.

With Rwd you're changing the final drive ratio. With Rwd, you are usually changing other gears.

[Weapon_R]

Originally posted by Ekliptix
I don't think that overdrive comment is right, but it's easy to do on Rwd cars but probably a lot harder to do on Fwd. I don't recommend it on your honda/acura unless you plan to go to the drag strip everyday.

I'm looking at this 98 GT stang for sale, seems really fun to drive and its got all the options, thats what i'm thinking of doing.

[T5_X]

keep in mind that highway gas mileage will go down with a high gear ratio, and I believe you will need your speedo/odometer recalibrated. I have my ranger geared at 3.73, I really like it, but I may go to a bit lower because my top end is horrible, and sometimes I wish I could go into third gear at around 100 and keep accelerating.

[Weapon_R]

Originally posted by Ranger_X31
keep in mind that highway gas mileage will go down with a high gear ratio, and I believe you will need your speedo/odometer recalibrated. I have my ranger geared at 3.73, I really like it, but I may go to a bit lower because my top end is horrible, and sometimes I wish I could go into third gear at around 100 and keep accelerating.

Have you noticed an increase in acceleration? And What good would it do, if it only reduces your speed in any sort of race? I see a lot of people doing it, but I don't really get the advantages. Would it even help in the 1/4?

[Ekliptix]

Originally posted by Ekliptix
I think that something like a 95 Camaro Z28 will lose 3/10th's in the 1/4 mile if they do this.

so something similar with a mustang.

[Davan]

I beleive it all dpepends on what you want to do with the car. If you need a straight line quater mile monster, vs a top-end high speed cruiser, you will want to select different gears.

[T5_X]

Originally posted by Weapon_R


Have you noticed an increase in acceleration? And What good would it do, if it only reduces your speed in any sort of race? I see a lot of people doing it, but I don't really get the advantages. Would it even help in the 1/4?

I'd imagine 3.73-4.10 would be best for 1/4 mile acceleration in the mustang, but I'm not too sure WHICH one would be better. Generally, the lower the gear (higher numerically) the better the time, but not trap speed

My transmission is geared very differently from a T-5 because it's designed for "truck" use, so I shouldn't have used it as an example. My first gear is very short for towing, with big spacing between the first, second and third and even fourth gears so going to a 4.10 would make it even shorter, therefore giving me a really good jump in low-end acceleration, but incresing the spacing between the gears, so mid-top end sucks. When I test my 0-60 time, I come just about to the end of third gear. If I had 4.10s, I'd have to shift into 4th before I reaced that speed. With the space between the gears, this means a large RPM drop-off between these gears, so the time for 0-40 would be greatly increased, but around 50+, my truck wouldn't be as quick, this is why I would probably get a quicker 1/4 mile time, but lower trap speed.
hope this helped a little

[Weapon_R]

It does greatly! Thank you! One thing though, let's use the 1998 GT Mustang as an example:

If I used 3.73 gearing, what would I experience, compared to stock:

From 0-60 (pure accelation)

0-60 (regular daily driving)

60-90 (Cruising speeds, normal driving)

100-140 (highway speeds)

Hehe sorry for all the questions, just very interested in this relatively simple mod that is supposed to do wonders. I don't really like it when a car roars at highway speeds, should be smooth and quiet, so would 3.73 make the engine totally rev higher than usual to maintain the same speeds?

[T5_X]

Well, there's 5 gears, so unless you were running 4.56s, I don't thing you'd have a problem with the engine "roaring" at normal highway speeds.

3.73s will definitly give you a very good 0-60 time, and you'll definitly still have enough top end for highway passing.

For a daily driver, I'd suggest the 3.73s. It won't strain your drivetrain as much and it'll get you better gas mileage than the 4.10s. It's an extremely common mod too.


But.... I'm no expert, so you should get a second opnion from someone who actually has a mustang.

[Weapon_R]

At approximately what speed will I top out at? And will installing these remind me of the integra, where I have trouble passing people on the highway, or will this thing still pick up? I don't imagine i'd ever go over 150kms unless i'm being stupid, but that is a rarity.

[T5_X]

Beyond my knowledge. If no one here knows, then try stangnet.com, they have thousands of members that can help you. Or maybe performance-shop.com

[4wheeldrift]

Higher numerical gears take from your top end and give you better acceleration. Why would you want to do this? Well, solo 2 for instance, where you want good acceleration out of the corners and you are never going to see more than 70mph on an average course. Drag racing is the same way, you want to be at your cars theoretical maximum speed in the last foot of the 1320. Salt flat speed trials, go crezzy with the lowest gearing you can possibly find, you've got 2 miles to get up to speed.

Here's an interesting article on pinion ratios:

http://www.wallaceracing.com/reargear.htm

[300rwhp]

3.73s would be perfect for 98 gt they are the best gear ratio out there for that car they will give good acceleration in any gear and your car will actually be able to go faster (top speed) because the 3.27(stock) gearing runs out of power band to reach at high top speed.

once when i first got my car i was very stupid and top speed trialled my car (using a gps becuase speedometers it unaccurate at really high speeds) using the stock ratio i got 240kmh with the 3.73s i got up to 274 before i ran out balls that was in fifth gear and i was at 5500 rpms i could have gone faster i think