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Gunner
5th December 2007, 11:03 PM
now, i wanna gear a t50 to work out similar to a c160,
my levin was a very quik car with a six speed, compared to the five speed 20v, like a good 4 lengths in a basic run.

anyone have any idea on whether i could get a similar result fukin with diff ratios, i kno its an obviuos yes, but can u get it to stay in the power band.

in the ae111, rev to 8 change up, and it u start again at just over 5, anyone got ratios like this with a blacktop?

Jonny Rochester
6th December 2007, 12:24 AM
TRD T50 gearset?

biggo
6th December 2007, 01:38 PM
4.77 diff

its the only way :P

RobertoX
6th December 2007, 04:15 PM
You can change at what rev the engine goes to as you change gears by changing the diff ratio. Here are some graphs of how the stock t50 changes when you change ratios between 3.9 and 4.1... The red 'saw tooth' line is where you will be operaing and the vertical lines are where you change gears, note the corresponding rpm

3.9
http://www.duivesteyn.net/rob/t50_3pt9.jpg


4.7
http://www.duivesteyn.net/rob/t50_4pt7.jpg
both use 195/50/15 tyres btw

I'll link to the spreadsheet that I used to make these later, it has ratios for TRD and quaife sets also and you can play with the final ratio to see how it affects things.


Here is a spreadsheet with the ratios: t50_ratios.xls (http://www.duivesteyn.net/rob/t50_ratios.xls)
Scroll left for the graphs, there are only graphs for the standard ratios, one of the TRD sets and the Quaife gearsets, you can play around with the diff ratio to see if you can get it to work like you want, you can see by the shape of the Quaife graph that it is much more even between the gears... No matter what final ratio you use with the standard box you will never have even shifts between all gears. (that may not be what you want though!)

RobertoX
10th December 2007, 06:17 PM
I've updated the spreadsheet and automated the traceline where you shift through the gears, you can play with the shift point and see how that affects things on the graph. just play with the 'inputs' that are highlighted in green, put in your diff ratio, tyre size and shift point and it will show you what your gear shifts will look like. (lol I was really bored at work today :P)

Looking at this I really want to get a quaife gear set now!

You can also change around the gear ratios on the top table on sheet2 to whatever you like.

T50 Gear ratios Spreadsheet (http://www.duivesteyn.net/rob/t50_ratios_2.xls)

Another thing to note is that when you change your diff ratio it doesnt change the rpm that you drop to when you change up a gear. Like if you want it to drop from 8000rpm to 6000rpm when you go from 2nd to 3rd you will not be able to fix this with a different diff ratio, you must get a new gear set (close ratio box).

Brenton 86
10th December 2007, 06:38 PM
i think the 4.7 graph is off unless im reading in wrong, its much closer than that

RobertoX
10th December 2007, 06:44 PM
Hmmm... you think? It's a pretty straight forward sum... (speed = rpm / gear ratio / diff ratio * tyre circumference *60/1000000)

What speed do you get with a 4.7 at a particular rpm say in first gear?
I mean looking at it, if you are in 5th and at 600rpm you are only going about 165...

Gunner
10th December 2007, 09:17 PM
thanks guys