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Old 12-31-2014, 06:24 AM   #97
Manji
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Join Date: Jun 2014
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Quote:
Originally Posted by nikitopo View Post
We are not discussing about higher final drive ratio, but about shorter! For example 4.1 -> 4.5

It is not only about more shifts. It is that you have to work in higher gears. Post #91 mentions it. He was normally using 3rd gear on a specific track and after the change he had to use 4th gear. Overall timing was worst.

When you go from a 4.1 to a 4.5 drive ratio you have a 10% increase, but using the 4th gear instead of the 3rd you have a 20% decrease. This is getting even worst when you have to shift into 5th or even 6th gear! That's why you lose.

Most advantages of a shorter final drive ratio can be seen on the 1st and 2nd gears, but these gears are not of much use in racing. I can imagine only a very tight race track which could get an advantage from this.


Even the decision to have a 4.1 ratio as standard was mainly for the "feeling" factor. A sports car that can achieve it's top speed only in overdrive (6th gear) is not a very good decision for racing! That is why it is very difficult to go with more than 200km/h (124 mph) in stock form ..
Higher final drive is correct. 4.5 is higher than 4.1. 4.5 is also taller. Higher/lower/shorter/taller, its all terminology.

I am telling you that it is track dependent. My comments about 4.5 being better at my track are not theory, they are fact. You can argue it all you like, but I don't need you to tell me what I already know.

Here is a video. I will talk you through it.
[ame]http://youtu.be/84dz5p3X-vw[/ame]
At 0.33 I had to chop down into 2nd with the 4.1. With the 4.5 it is quicker for me to stay in 3rd now. 2 gear changes saved.

From 0.50 - 1.04 I can stay in 3rd as I did with the 4.1FD, but with the 4.5FD I'm faster through here as I'm higher in the rev range

From 1.05 - 1.12 with the 4.1FD this was an awkward section. If I left in 3rd I had to ride the limiter. If I went for 4th,it was the wrong gear for the corner, so had to go back to 3rd after only having been in 4th for a moment. With the 4.5FD I grab 4th earlier, and can take the corner in 4th. So downshift saved.

1.12 - 1.19 with 4.5 I can stay in 4th. With 4.1 I stay in 3rd.

Little straight after 1.19 with 4.5 I am already in 4th. 4.1FD I need to get into 4th.

Main straight. 4.1FD and 4.5FD I go 3rd 4th 5th. I don't run out of 5th gear with the 4.5FD.

1st corner off the straight, I used 3rd with both FD's, but with the 4.5FD it pulled better.

I'll say it again, its track dependent! For me, its better on my track to have a 4.5. But if I went to 4.8 it would all change. I'd need 6th on the straight, and the section after the hairpin I would run out of 3rd.

You set your gearing for the track you are on. With my race car, I have different diff nuggets I use for different tracks. And I don't need to check a forum to argue about which will be quicker.
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