Gearbox's gear ratios calculator

21st October 2004

Finally - this file - a self calculating / semi-automatic - excel file is uploaded for other people to download and use.

This is a sad event, because it is an attempt to help people (spoon feeding actually!!! means not helping people to think for themselves, but instead make them reliant of other people even more, that's why it is sad.) to have a better understanding of the gearbox workings.

In this file, contains gear ratios for the typical FR T50 gearbox used by the famous Toyota Corolla Sprinter AE86 found in Initial_D anime cartoon as well as numerous Toyota Corona TT132 & TT141 and Cressidas of the 80s era. One of the three different types of close ratio from TRD is also put in for quick comparisons.

The current trend of FF gear box ratios are also included from the C52, C56 (both 5 speed) to the much greed-ed C60 (6 speed gearbox). These came from the famous 4A-G of 16v as well as 20v from the era of early 90s to late 90s.

So, how to use the file?

After downloading the file, first key in the engine rpm desired. 8,000 rpm was put in as default as this is the figure nearly everyone can achieve without problem. Then key in the tyre's circumference, again in this case 1.8 meters was chosen as the typical representation of regular road tyres of specifications from 195/50R15 or 185/60R14 and the likes.

Then simply read of the vehicle speed on the right hand column of the respective gear ratios.

Interpretation of Results

Normally, if the vehicle speed is slower than the other under compared gear ratio, then it means it has more torque, which usually means better acceleration, while sacrificing higher speed.

Normally, if the vehicle speed is higher than the other under compared gear ratio, then it means it has less torque, which usually means weaker acceleration, although higher vehicle speed, but will achieve the particular top speed much longer time than required compared to the other gears.

So, with this file, hope you guys will have fun ............

Car/T50/gearbox ratio calculator.xls


Oh, nearly forgot to mention, having higher torque is always better than higher vehicle speed. Well, nearly always anyway.................



oh, the other post reminded me about the the 11,000 rpm scenario

So, when you guys play with the file, key in 11,000 rpm instead of 8,000 and see how the vehicle speed increase.

You'll soon realise that if this is the case, then takumi is cornering so much faster than before.

In reality using standard gear ratio would be impossible for a 11,000 rpm engine - close ratios is a MUST.

The example can be clearly show in the TRD T50 close ratio case. Oh in my file I didn't use the 4.7 final drive, so please change it.

Once you use 11,000 rpm with TRD close ratios with 4.7 final, you'll see the vehicle speed drop back to managle figures = means = drivable.

You may ask - why the do we want to reduce the vehicle speed back smile.gif - hehehhehe

If you ask this questions - then .......... suspense smile.gif think about it lar smile.gif

The answer is "applied torque" - "successfully" - "transferred to the ground" - "translate to" = MUCH MORE GRIP -


by the way - read it in "Tune to Win" by the late "Carol Smith" recommended by



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