Hello yalakom,
Transmission strength has been discussed before... Quick search brought up
transmission strength question (reply #5) and
3RZFE to G52?? (reply #2).
One of the best examples for the W-series is the dealer-equipped supercharger option of the 2.7-liter 3RZ-FE 4cyl powered 1st gen Tacoma. This does not void the drivetrain warranty and promises torque in the 240 lb-ft range in a vehicle heavier than yours.
I could have installed an R-series transmission, but wanted the lower 1st gear for wheelin' and the W56 was easy to find.
redneckcustoms13 is correct.
| Year | Application | Engine | Model | 1st gear |
| 1986-1987 | Hilux Pickup/4Runner | 2.4-liter 22R-TE | R151F | 4.31:1 |
| 1988-1995 | Hilux Pickup/4Runner | 3.0-liter 3VZ-E | R150F | 3.83:1 |
| 1993-1994 | T100 | 3.0-liter 3VZ-E | R150F | 3.83:1 |
| 1995-1998 | T100 | 3.4-liter 5VZ-FE | R150F | 3.83:1 |
| 1995-2004 | Tacoma/4Runner | 3.4-liter 5VZ-FE | R150F | 3.83:1 |
| 2000-2004 | Tundra | 3.4-liter 5VZ-FE | R150F | 3.83:1 |
The R151F was only used for 2 years and of those the Turbocharged models were of the minority built. They are very difficult to find. For this reason selecting the 3.95:1 W-series wasn't such a bad choice...
can the W56 be rebuilt to take the 300 hp?
...well this depends on how much torque you're outputting and at what RPM. One good thing going for you is that you are using a car engine, and not only that, but one with a wide-valve angle 'G' type cylinder head, which, back in the day was optimized and believed necessary for high RPM output. (Nowadays narrow valve angles are outflowing the wide valve angle designs of yesteryear.) Further, this is an older Turbo engine design which requires time to spool (i.e. no twin entry or variable geometry and/or intake runner length or similar turbo spool enhancing technologies) thereby raising the peak torque power band well above that of a truck engine.
We never got the 1JZ-GTE in the U.S. of A. According to the Wiki, it is rated for 268 lb-ft at 4,800 RPM. In comparison, the Supercharged 3RZ-FE should hit it's peak torque of ~240 lb-ft closer to 4K RPM, and when we compare power bands, the 1JZ-GTE won't have much usable torque under 4K whereas the 3RZ-FE will have probably 80% of it's torque available almost as early as 3K RPM.
One bad thing going for you is that the 1JZ-GTE is an inline engine which, compared to V-configured engines of similar bore/stroke/compression, typically develop more bottom end torque. As mentioned, fortunately this is being offset by 1) the "G" cylinder head optimized for higher RPM power, and 2) turbos are slow (lag) to develop positive manifold pressure.
Remember bearings and gears have a higher dynamic torque rating than static, so static torque loading is more damaging to a drivetrain than dynamic. So whenever we can get parts spinning before the torque comes in, the more durable they are and a longer life should be expected. This isn't to say "ohh so if I clutch dump at a higher RPM then it's better" as revving in neutral the transmission output shaft is at zero RPM
What it means is that a car engine tends to be less damaging to drivetrain parts than a truck engine that is designed for higher torque at lower RPMs.
Really the question that begs to be asked is why would one choose to run the 1JZ-GTE at stock boost when there are plenty of better even normally aspirated options in a truck than this, so..................how much do you plan to turn up the boost?
That is what's important to the W56 concern as even in stock form the 1JZ-GTE is pushing it's limits. Again, for the sake of a work truck, at least the 1JZ-GTE is a "wimpy car engine". From your concern and desire for a low(er) 1st gear I'd like to assume you've actual plans of a more than moderate Rock Crawler...........but then why a car engine for a Rock Crawler.........with only 8.5:1 compression..........and worse one with a snail attached to it's exhaust manifold...........
can the R series gear ratios be changed so as to have a lower 1st gear?
Yes, however you'd have to change both the input & counter shafts which would change gear ratios 1-3. You cannot simply change first gear. You'd be doing this by finding a donor R151F which as mentioned is difficult to find.
Doesn't the R-series need some kind of adapter for a gear-driven T-case
Only the R150F. See
https://www.marlincrawler.com/transfer-case/line-ups/transmission-to-transfer-case-adapters The R151F is native to the RF1A gear drive t/case.
Regards,
BigMike
