Final Drive: 4.56 vs. 4.88

[Toyota86.ir]

For NA i recommend 4.72 or 4.88 , personally prefer 4.88 from weir

[nikitopo]

Originally Posted by mcbrawr

I guess my next question would be this:

Looking at the MFactory gearing calculator, I will have to be in 5th gear to hit 100mph. With 4.88 gears how will 5th feel? Like 4th currently?

You will have actually less acceleration when you hit 100mph in 5th gear. Reason is that 5th gear is 17% slower comparing to 4th gear. You gain a bit with the shorter drive ratio, but not so much. Overall, you lose in this range of speed.


This is the common thing that most people don't get it. With a shorter drive ratio (e.g. 4.56, 4.88 etc.) you are actually slower in the higher range of speeds and faster in the lower range of speeds. There isn't such a magic that will give you the "missing" engine power. By changing the drive ratios, you are just shifting your available power band in another area.

[Foulsmell]

Originally Posted by nikitopo

You will have actually less acceleration when you hit 100mph in 5th gear. Reason is that 5th gear is 17% slower comparing to 4th gear. You gain a bit with the shorter drive ratio, but not so much. Overall, you lose in this range of speed.


This is the common thing that most people don't get it. With a shorter drive ratio (e.g. 4.56, 4.88 etc.) you are actually slower in the higher range of speeds and faster in the lower range of speeds. There isn't such a magic that will give you the "missing" engine power. By changing the drive ratios, you are just shifting your available power band in another area.

The OPs car is his DD so I doubt he will be hitting 100 mph on a regular basis.

When selecting 5th you are well into the power band and the acceleration does not feel as though it looses momentum. It may do on a stop watch but in real life it doesn't.

[bfrank1972]

Originally Posted by nikitopo

You will have actually less acceleration when you hit 100mph in 5th gear. Reason is that 5th gear is 17% slower comparing to 4th gear. You gain a bit with the shorter drive ratio, but not so much. Overall, you lose in this range of speed.


This is the common thing that most people don't get it. With a shorter drive ratio (e.g. 4.56, 4.88 etc.) you are actually slower in the higher range of speeds and faster in the lower range of speeds. There isn't such a magic that will give you the "missing" engine power. By changing the drive ratios, you are just shifting your available power band in another area.

Actually there are even more factors - in the end lower rear end gearing will make the car feel more responsive and accelerate harder in a given gear. But you'll have to shift sooner - compared to a stock geared car, the stock geared car will still be accelerating, while the re-geared car has to shift to a higher gear ratio. You're right - there's no free lunch. One of the main advantages to lower rear gears in drag racing is it takes less time to get the car moving and in its power band. Once in it's power band (assuming the gear spacing is correct), the differences will be less than you think. Caveat: on a track, if you change the rear ratios it might allow you to take full advantage of a straight stretch if the ratios are right... or it could prove a disadvantage if it forces you run out of RPM's at the end of a straight. Overall performance aside, for street driving, the added responsiveness and feel of acceleration in a given gear will make the car much more fun to drive!

[nikitopo]

Originally Posted by Foulsmell

The OPs car is his DD so I doubt he will be hitting 100 mph on a regular basis.

Yes this can be an argument. Personally, I am in Germany and we drive differently here. Even small tracks go with 100 mph ..

[Foulsmell]

Originally Posted by nikitopo

Yes this can be an argument. Personally, I am in Germany and we drive differently here.

You lucky lucky person. 😄

[mcbrawr]

Originally Posted by Foulsmell

The OPs car is his DD so I doubt he will be hitting 100 mph on a regular basis.

When selecting 5th you are well into the power band and the acceleration does not feel as though it looses momentum. It may do on a stop watch but in real life it doesn't.

I hit 100mph pretty regularly on some of the roads to/from my work because there are no homes, no residents, and nothing around to harm from speeding. So the tldr; is that 5th will be slower than stock but 1-4 will likely be quicker?

[Foulsmell]

Originally Posted by mcbrawr

I hit 100mph pretty regularly on some of the roads to/from my work because there are no homes, no residents, and nothing around to harm from speeding. So the tldr; is that 5th will be slower than stock but 1-4 will likely be quicker?

No way 5th is slower.

I did a test run before exhaust and FD fit (otherwise stock)

2nd @30mph then through the gears to 90mph.

Totally stock 13sec
FD and exhaust 11sec

No ecu tune.

I think that answers your question.

[Toyota86.ir]

Increasing fd ratio by 10% make you feel it response 10% better but overal acceleration from zero to 130miles will not increase over 5%

[SUB-FT86]

Originally Posted by Foulsmell

I went for 4.67 Mfactory on my DD M/T. It's perfect. Easier to drive than before due to the extra torque and comfortable cruising at higher speeds.

I realize that sometimes our cars feel kinda lazy to move around 2800 rpms and the engine feels kind of breathless(torqueless). How does the 4.67 combat that?

[Foulsmell]

Originally Posted by SUB-FT86

I realize that sometimes our cars feel kinda lazy to move around 2800 rpms and the engine feels kind of breathless(torqueless). How does the 4.67 combat that?

Basically by multiplying the torque that the engine puts out.

The breathless feeling has gone from my car now. I thought the same as you. I notice the difference more in 3rd and 4th gear where it just keeps pulling.

No matter what gear I'm in I always feel like there is enough power to pull away.

I liken it more to my friends 350z now but with a few more revs.

[SUB-FT86]

Originally Posted by Foulsmell

Basically by multiplying the torque that the engine puts out.

The breathless feeling has gone from my car now. I thought the same as you. I notice the difference more in 3rd and 4th gear where it just keeps pulling.

No matter what gear I'm in I always feel like there is enough power to pull away.

I liken it more to my friends 350z now but with a few more revs.

Wow, so it feels about as torque-y as a 350Z in FEEL right? I remember when I first drove a Z the torque won me over in a big way more than the car overall.

[skye67]

As a owner of a auto tranny with a 4.67, and a former owner of a manual. The biggest mistake Subaru and Toyota did was not to put the right gear ratio in this car. With the 4.67, this car rocks!! With the manual I could only wish to get to 135. But in the auto with gears, I can touch 135 with easy, offen. And the way it goes though the gears is just fantastic. This should be the first mod to the car.

[nikitopo]

Your statement doesn't make sense. Auto tranny has bigger power losses and a much smaller top speed (130 mph vs. 140 mph of the manual tranny). You cannot get an improvement on top speed by changing the final drive to a shorter ratio. This is a well know fact valid for ages. Did you buy the car second hand? Your car should also have some other mods.