Toyota had love for the W Transmission. Various versions were used over 34 years of production. That is sick! And it means there are tonnes of variations and gearsets available for us to potentially play with and perhaps make a real close ratio gear box. Well… almost… or so it appears.
First of all… I couldn’t find solid documentation on the early W4X and up to W52 transmissions, but they look to offer additional ratios that may or not be helpful. How those ratios would play out with W55 or 58 input shaft ratio’s though was unclear. Someone is going to have to pull one apart and figure it out.
And that’s basically how we can explore modifying W trannies to get better ratios for real driving. The W58 uses the exact same gears as the W55, but offers closer ratios via different input shaft gears. So… from the W55 and W58 alone we can find no gains… but interestingly, Toyota made a couple of different versions of the W tranny intended for use in trucks… and these therefore utilize different ratios.
Here is a look at the stock W58, again with 4.3 gears and the 195/60 14 rubber. Compared to the stock T50 we looked at yesterday. 1st and 2nd are a little closer together, 2nd to 3rd suffers a bit, but 3, 4 and 5 are a lot more evenly spaced. It’s all visible in this cheezy 90’s animated gif. Note I was too lazy to label which is which. If you can’t figure it out, you don’t really care… and if you don’t care neither do I.
Anyways… I said we could do some interesting things here… and we sort of can. Take a look at this.
This gear box is based on the input shaft ratio used in the W55, 56 and 59 transmissions. It is using second gear from a W56 with a ratio of 2.141 as it’s FIRST gear. Still using the 4.3 final drive and a tire diameter of 590mm, we get 90km/h at 7500rpm. SECOND gear is the stock W55 or 56 third gear, with a ratio of 1.384:1. THIRD gear is where it all breaks down. 1.275 is the only thing available betwen 1.384:1 and 1:1 so… a gear has to be made, and apparently this can be done for a few hundred bucks. A lot cheaper than a few thousand …
But… Disappointing.
I spec’ed 1.178:1 as a ratio. This is a ratio that would be available to us using the W58 input shaft set, but… that actually makes other things more difficult.
Finally, fifth gear is the base W55/56 ratio of 0.85:1.
If you want to play or look further… you can download my spreadsheet here. I know it’s hack, but it’s minutes. I’m sure there is better stuff online already but… I’m too lazy to look. If you are too… take it.
spreadsheet link fixed. I had to zip it myself.